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1

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

2

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

3

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

4

Biosorption of heavy metals  

SciTech Connect

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

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

1995-05-01

5

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...

6

SULFIDE PRECIPITATION OF HEAVY METALS  

EPA Science Inventory

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

7

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

8

Heavy Metal Pumps in Plants  

SciTech Connect

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 these plants to help clean up toxic metals from soils. A rate limiting step is using plant for bioremediation is the normally poor capacity of plants to concentrate toxic metals. Our interest in metal ion transport systems includes those for essential mineral nutrients such as molybdenum, copper, iron, manganese, as well as toxic metals such as cerium, mercury, cesium, cadmium, arsenic and selenium. Understanding the pathways by which toxic metals accumulate in plants will enable the engineering of plants to exclude toxic metals and create healthier food sources, or to extract toxic metals from the soil as a strategy to clean up polluted lands and water.

Harper, J.F.

2000-10-01

9

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

10

MTH734U-MTHM012 Autumn 2012 Topics in Probability & Stochastic Processes  

E-print Network

at a counter according to a Poisson process of rate . An arriving particle is recorded with probability pMTH734U-MTHM012 Autumn 2012 Topics in Probability & Stochastic Processes Problem Sheet 3 1. Suppose of you have left the post office? 2. Customers enter a store according to a Poisson process with rate

Stark, Dudley

11

OXFORD BIBLIOGRAPHIES IN ECOLOGY "HEAVY METAL TOLERANCE"  

E-print Network

Bacteria Plants and Other Non-Animal Eukaryotes Animals Genetics and Evolution Bacteria Plants Animals and Restoration Phytoextraction of Heavy Metals Genetic Engineering for Metal Tolerance Model Organisms genetically engineered organisms that may be useful to solve environmental problems caused by heavy metal

Rajakaruna, Nishanta

12

Industrial hygiene of selected heavy metals  

SciTech Connect

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

Woodring, J.L.

1993-08-01

13

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

14

Heavy metal frost on Venus  

NASA Astrophysics Data System (ADS)

Chemical equilibrium calculations of volatile metal geochemistry on Venus show that high dielectric constant compounds of lead and bismuth such as PbS (galena), Bi 2S 3 (bismuthite) or Pb-Bi sulfosalts condense in the venusian highlands and may be responsible for the low radar emissivities observed by Magellan and Pioneer Venus. Our calculations also show that elemental tellurium is unstable on Venus' surface and will not condense below 46.6 km. This is over 30 km higher than Maxwell Montes, the highest point on Venus' surface. Elemental analyses of Venus' highlands surface by laser induced breakdown spectroscopy (LIBS) and/or X-ray fluorescence (XRF) can verify the identity of the heavy metal frost on Venus. The Pb-Pb age of Venus could be determined by mass spectrometric measurements of the Pb 207/Pb 204 and Pb 206/Pb 204 isotopic ratios in Pb-bearing frosts. All of these measurements are technologically feasible now.

Schaefer, Laura; Fegley, Bruce

2004-03-01

15

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

16

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

17

Community Heavy Metal Exposure, San Francisco, California  

Microsoft Academic Search

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

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

2008-01-01

18

Schematic Information Processing of Heavy Metal Lyrics  

Microsoft Academic Search

Schematic processing of heavy metal lyrics was tested by comparing subjects in two cognitive load conditions. Subjects were either provided with the written lyrics (low cognitive load) or not (high cognitive load) as they listened to heavy metal songs with four common themes: sex, suicide, violence, and occult. Schematic processing was evidenced by the pattern of results across three experiments:

CHRISTINE HALL HANSEN; RANALD D. HANSEN

1991-01-01

19

Heavy Metal Speciation in Sewage Sludge  

Microsoft Academic Search

Sewage sludge is a rich source of organic matter and nutrients, so there is a possibility of their broader agricultural utilization. However, agricultural utilization of this material is limited by excessive quantities of heavy metals. In accordance with this, the current paper presents the results of investigations referring to the speci- ation of heavy metals in selected sewage sludge. It

M. Jakubus; J. Czeka?a

20

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...

21

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

22

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

23

Resistance of environmental bacteria to heavy metals  

Microsoft Academic Search

Bacteria were isolated from different naturally polluted environments. Metal-resistant bacteria were selected and minimal inhibitory concentrations of heavy metals (MICs) for each isolate were determined. In addition, the mobility of the most important metallic cations (Cu, Zn, Cr, Cd, Co, Hg) was evaluated by comparing results obtained by two tests of toxicity in solid and liquid media. Results of the

A. Hassen; N. Saidi; M. Cherif; A. Boudabous

1998-01-01

24

Experimental perspectives on heavy electron metals  

SciTech Connect

We motivate the description of heavy electron metals in terms of concepts from the Kondo problem. These concepts are used to discuss magnetism and superconductivity in heavy electron systems. Particular attention is given to what we view as the principal outstanding questions in this field and direction in which the field is developing. This will include consideration of the differences between Ce and U heavy electron compounds, as well as the occurrence of very small ordered magnetic moments. 26 refs., 5 figs.

Fisk, Z.; Ott, H.R.; Aeppli, G.

1987-01-01

25

Removal of heavy metals from waste streams  

SciTech Connect

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

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

1988-07-19

26

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

27

Heavy metal contamination from geothermal sources.  

PubMed

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

Sabadell, J E; Axtmann, R C

1975-12-01

28

Heavy metal removal and recovery using microorganisms  

SciTech Connect

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

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

1991-02-01

29

Heavy Metal Risk Management: Case Analysis  

PubMed Central

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

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

2012-01-01

30

[Yeasts--biosorbents of heavy metals].  

PubMed

The sharp increase of the level of environment pollution by heavy metals caused the increase of interest to the problem of live organisms (including microorganisms) resistance to these metals. Biosorption is one of the mechanisms of microorganisms resistance to heavy metals. Yeasts as biosorbents are of special interest. An analysis of the data from literature have shown that the yeast biomass may be used successfully as biosorption material for such metals as Ag, Au, Cd, Co, Cr, Cu, Ni, Pb, U, Th, Zn. Yeasts of genera Saccharomyces, Candida, Pichia are efficient biosorbents of metals. The sorptional system estimation is based on the classic sorption isotherm obtained in the course of equilibrium experiments and depends on pH, properties of metal ions, biomass concentration, preliminary physical or chemical treatment of the biomass, presence of various organic and inorganic ions and on temperature. The yeast biomass may be obtained using numerous industrial processes, that decreases considerably the biosorbent cost. Most yeasts can sorb a wide range of metals or be strictly specific in respect of only one metal. Special attention would be paid to the cell wall which structure determines sorption proceeding mechanisms. Problems of mechanisms of heavy metal biosorption by microorganisms at molecular level are discussed. The review also deals with the newest developments on improving the biosorption processes in microorganisms, yeast in particular. PMID:15104060

Podgorski?, V S; Kasatkina, T P; Lozovaia, O G

2004-01-01

31

Heavy metal contaminants in yerberia shop products.  

PubMed

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

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

2013-03-01

32

Heavy metal poisoning and cardiovascular disease.  

PubMed

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

Alissa, Eman M; Ferns, Gordon A

2011-01-01

33

Heavy Metal Humor: Reconsidering Carnival in Heavy Metal Culture  

E-print Network

and Butthead depict metal culture imagery and ideals humorously. Further, their creators, Brendan Smalls and Mike Judge are involved in metal culture.ii 3 But their work, being animated and presented on television, goes through many hands with other... to automate positions previously held by humans and connect offices in less 17 expensive countries to businesses in the United States (Pfanner 2012). Consequently, owners of businesses increased worker productivity and lower labor cost to become...

Powell, Gary Botts

2013-06-05

34

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

35

Heavy metal hazards of Nigerian herbal remedies.  

PubMed

The uses of herbal products are not regulated in Nigeria and in many low-income countries and are freely available to everyone. The safety of these herbal medicines is poorly understood. This study characterizes the content of cadmium, copper, iron, nickel, selenium, zinc, lead and mercury in a random sample of Nigerian traditional products. Ready-to-use herbal products were purchased from the open market and digested using HNO3.The heavy metal content of the digested filtrate was determined by atomic absorption spectrometry Uni-cam Model 929. The result showed that 100% of the samples contained elevated amounts of heavy metals. These data alert us to the possibility of heavy metal toxicity from herbal products in Nigeria. The public health hazards from ingestion of herbal medicines should be identified and disclosed by in-depth risk assessment studies. PMID:16759683

Obi, E; Akunyili, Dora N; Ekpo, B; Orisakwe, Orish E

2006-10-01

36

Treatability of Stormwater Heavy Metals  

E-print Network

stormwater. Hydraulic Studies Metals Capture Media Amended Soils Role of Grasses Role of p Metal Associations for Chemical Treatment · Type 1 water: high turbidity, >100 NTU, and high alkalinity, >250 mg/L as CaCO3 (easiest water to coagulate, many effective options). · Type 2 water: high turbidity and low alkalinity

Clark, Shirley E.

37

Heavy metal distribution in household waste  

SciTech Connect

The present study was undertaken at the request of the French Ministry of Environment with the help of the national agency for waste recovery and disposal (ANRED) and the company Valorga. The aim of this paper is to report the original methods of assessment and relevant results in visual form. Knowledge of the distribution of each heavy metal (mercury, cadmium, lead, nickel, chromium, zinc and copper) in the different parts or components of household refuse will allow the development of both statutory safeguards on the disposal of products such as batteries, a source of heavy metals, and of effective technological treatment of the granulometric fractions which are richest in toxic elements.

Rosseaux, P.; Navarro, A.; Vermande, P. (Institut National des Sciences Appliques, Villeurbanne (France))

1989-09-01

38

Transport and distribution of heavy metals in Cauvery river  

Microsoft Academic Search

Heavy metal transport in Cauvery river chiefly takes place in the particulate form. Tributaries Hemevathi and Kabini draining highly mineralized areas contribute significantly to the heavy metal load of the Cauvery river. Particulate metal transport is influenced by the presence of major dams built across the river. Factor analysis of the elemental data identifies two major group of heavy metals,

P. Vaithiyanathan; Al. Ramanathan; V. Subramanian

1993-01-01

39

BjDHNs Confer Heavy-metal Tolerance in Plants  

Microsoft Academic Search

Dehydrin gene transcript could be induced by heavy metals, and some dehydrins possess the ability to bind metals. However,\\u000a the correlation between dehydrins and heavy-metal stress is unknown. In order to elucidate the contribution of dehydrins to\\u000a heavy-metal stress tolerance in plants, we cloned two SK2-type dehydrin genes from heavy-metal hyperaccumulator Brassica juncea, and investigated their Cd\\/Zn tolerance in transgenic

Jin Xu; Yu Xiu Zhang; Wei Wei; Lu Han; Zi Qiu Guan; Zi Wang; Tuan Yao Chai

2008-01-01

40

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

41

Heavy metals in traditional Indian remedies  

Microsoft Academic Search

The growing popularity of traditional Indian remedies necessitates a critical evaluation of risks associated with their use. This systematic review aims at summarising all available data relating to the heavy metal content in such remedies. Computerised literature searches were carried out to identify all articles with original data on this subject. Fifteen case reports and six case series were found.

E. Ernst

2002-01-01

42

REMOVAL OF HEAVY METALS BY ARTIFICIAL WETLANDS  

EPA Science Inventory

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

43

Heavy metal distribution in household waste  

Microsoft Academic Search

The present study was undertaken at the request of the French Ministry of Environment with the help of the national agency for waste recovery and disposal (ANRED) and the company Valorga. The aim of this paper is to report the original methods of assessment and relevant results in visual form. Knowledge of the distribution of each heavy metal (mercury, cadmium,

P. Rosseaux; A. Navarro; P. Vermande

1989-01-01

44

Hydroponics reducing effluent's heavy metals discharge.  

PubMed

This paper investigates the capacity of Nutrient Film Technique (NFT) to control effluent's heavy metals discharge. A commercial hydroponic system was adapted to irrigate lettuces with primary treated wastewater for studying the potential heavy metals removal. A second commercial hydroponic system was used to irrigate the same type of lettuces with nutrient solution and this system was used as a control. Results showed that lettuces grew well when irrigated with primary treated effluent in the commercial hydroponic system. The NFT-plant system heavy metals removal efficiency varied amongst the different elements, The system's removal efficiency for Cr was more than 92%, Ni more than 85%, in addition to more than 60% reduction of B, Pb, and Zn. Nonetheless, the NFT-plants system removal efficiencies for As, Cd and Cu were lower than 30%. Results show that lettuces accumulated heavy metals in leaves at concentrations higher than the maximum acceptable European and Australian levels. Therefore, non-edible plants such as flowers or pyrethrum are recommended as value added crops for the proposed NFT. PMID:19151500

Rababah, Abdellah; Al-Shuha, Ahmad

2009-01-01

45

Heavy Metal Music and Adolescent Suicidal Risk  

Microsoft Academic Search

This study probes the differentiating characteristics (family relationships, social–psychological attitudes, drug use, and suicidal risk) of youth who prefer heavy metal (HM) music, worship music, and use music for vicarious release. Data analysis was based on a sample of 275 secondary school students between the ages of 14 and 18. Logistic regressions revealed that HM music preference and worshipping is

Eric Lacourse; Michel Claes; Martine Villeneuve

2001-01-01

46

Heavy Metal Music and Adolescent Suicidal Risk  

Microsoft Academic Search

This study probes the differentiating characteristics (family relationships, social- psychological attitudes, drug use, and suicidal risk) of youth who prefer heavy metal (HM) music, worship music, and use music for vicarious release. Data analysis was based on a sample of 275 secondary school students between the ages of 14 and 18. Logistic regressions revealed that HM music preference and worshipping

Eric Lacourse; Michel Claes; Martine Villeneuve

2001-01-01

47

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...

48

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

49

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

50

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

51

Toxicity assessment of heavy metal mixtures by Lemna minor L  

Microsoft Academic Search

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

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

2007-01-01

52

A Fuzzy Model of Heavy Metal Loadings in Marine Environment  

E-print Network

, Morecambe Bay, heavy metal concentrations, index of spa- tial distribution, spatial data analysis. 1A 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

Kuncheva, Ludmila I.

53

Heavy metal removal from wastewater in fluidized bed reactor  

Microsoft Academic Search

An innovative process for removing heavy metals including Cu, Ni and Zn from industrial wastewater has been developed. The new technology was based on inducing the nucleated precipitation of heavy metals on the sand surface in a fluidized bed reactor. The results showed that pH had a great effect on heavy metal removal efficiency and the optimum pH was about

Ping Zhou; Ju-Chang Huang; Alfred W. F Li; Shirly Wei

1999-01-01

54

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, and clinical toxicology. A number of techniques have been developed over the years for heavy metal ion analysis-resolution differential surface plasmon resonance (SPR) sensor for heavy metal ion detection. The sensor surface

Chen, Wilfred

55

Heavy metals in avian eggshells: Another excretion method  

Microsoft Academic Search

Birds can rid their bodies of heavy metals through both excretion and deposition in feathers, and females can also eliminate heavy metals in the contents of their eggs. In this paper the levels of heavy metals (lead, cadmium, mercury, selenium, manganese, chromium) in the contents and shells of eggs of roseate terns (Sterna dougallii,) and herring gulls (Larus argentatus) nesting

Joanna Burger

1994-01-01

56

Bacterial sorption of heavy metals  

SciTech Connect

Four bacteria, Bacillus cereus, B. subtilis, Escherichia coli, and Pseudomonas aeruginosa, were examined for the ability to remove Ag{sup +}, Cd{sup 2+}, Cu{sup 2+}, and La{sup 3+} 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 Cd{sup 2+} and Cu{sup 2+}, 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 Cd{sup 2+} removal and B. subtilis removed the most Cu{sup 2+}. Removal of Ag{sup +} from solution by bacteria was very efficient; an average of 89% of the total Ag{sup +} was removed from the 1 mM solution, whereas only 12, 29, and 27% of the total Cd{sup 2+}, Cu{sup 2+}, and La{sup 3+}, respectively, were sorbed from 1 mM solutions. Electron microscopy indicated that La{sup 3+} accumulated at the cell surface as needlelike, crystalline precipitates. Silver precipitated as discrete colloidal aggregates at the cell surface and occasionally in the cytoplasma. The results indicate that bacterial cells are capable of binding large quantities of different metals.

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

1989-01-01

57

Insoluble mixed heavy metal polysulfide cathodes  

SciTech Connect

This patent describes an electrochemical cell comprising an anode, an electrolyte, and a solid active cathode. Wherein the cathode is comprised of one or more mixed heavy metal polysulfides having the formula M(1){sub w}{sup + n}M(2){sub x }{sup + m}(S{sub y)z} {sup {minus} 2} wherein M(1) and M(2) are different heavy metal atoms, n and m are integers representing the valence states of M(1) and M(2) respectively, w and x are non zero integers representing the stoichiometry of M(1) and M(2) respectively in the polysulfide, S is sulfur, nw + mx = 2z and y is greater than 4.5.

Bowden, W.L.; Demuth, D.L.; Barnette, L.H.

1990-01-02

58

Bismuth film electrodes for heavy metals determination  

Microsoft Academic Search

Bismuth film electrodes (BiFEs) have a potential to replace toxic mercury used most frequently for determination of heavy\\u000a metals (Cd, Pb, Zn) by anodic stripping voltammetry. We prepared a graphite disc electrode (0.5 mm in diameter) from a pencil-lead\\u000a rod and developed a nitrogen doped diamond-like carbon (NDLC) microelectrode array consisting of 50,625 microdiscs with 3 ?m\\u000a in diameter and interelectrode distances

Vlastimil Rehacek; Ivan Hotovy; Marian Vojs; Fedor Mika

2008-01-01

59

Bismuth film electrodes for heavy metals determination  

Microsoft Academic Search

Bismuth film electrodes (BiFEs) have a potential to replace toxic mercury used most frequently for determination of heavy metals (Cd, Pb, Zn) by anodic stripping voltammetry. We prepared a graphite disc electrode (0.5 mm in diameter) from a pencil-lead rod and developed a nitrogen doped diamond-like carbon (NDLC) microelectrode array consisting of 50 625 microdiscs with 3 mum in diameter

Vlastimil Rehacek; Ivan Hotovy; Marian Vojs; Fedor Mika

2007-01-01

60

Heavy Metal Exposure from Personal Care Products  

Microsoft Academic Search

Numerous studies have described human exposure to heavy metals from diverse sources in Nigeria, but little is known about\\u000a the exposure from personal care products, and few or no report is available on the personal care product concentrations of\\u000a cadmium, chromium, copper and zinc, which have biotic effects. The levels of these elements were determined in 74 samples\\u000a of 5

J. G. AyenimoA; A. M. Yusuf; A. S. Adekunle; O. W. Makinde

2010-01-01

61

Heavy metals in carabids (Coleoptera, Carabidae)  

PubMed Central

Abstract Carabid beetles (Coleoptera, Carabidae) are one of the most studied soil groups in relation to heavy metal (HM) accumulation and use for bioindication of environmental pollution. Accumulation of Zn and Cu in carabid beetles was species-, sex- and trophic group-specific. No differences were found in HM contents between omnivorous and carnivorous species. The use of carabid beetles as indicators of HM accumulation appears to be rather limited. PMID:21738414

Butovsky, Ruslan O.

2011-01-01

62

Isolation and characterization of a heavy metal-resistant Burkholderia sp. from heavy metal-contaminated paddy field soil and its potential in promoting plant growth and heavy metal accumulation in metal-polluted soil  

Microsoft Academic Search

A heavy metal-resistant bacterial strain was isolated from heavy metal-contaminated soils and identified as Burkholderia sp. J62 based on the 16S rDNA gene sequence analysis. The heavy metal- and antibiotic resistance, heavy metal solubilization of the isolate were investigated. The isolate was also evaluated for promoting plant growth and Pb and Cd uptakes of the plants from heavy metal-contaminated soils

Chun-yu Jiang; Xia-fang Sheng; Meng Qian; Qing-ya Wang

2008-01-01

63

Plant rhamnogalacturonan II complexation of heavy metal cations  

DOEpatents

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

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

1999-01-01

64

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

65

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

66

Variations in Heavy Metals Across Urban Streams  

NASA Astrophysics Data System (ADS)

Urbanization has led to increased concentrations of metals such as lead (Pb), zinc (Zn), and copper (Cu) in streams due to industrial sources, domestic activities, vehicle use, and runoff from roadways. These metals can be dangerous to aquatic organisms and humans at high concentrations. We investigated variations in concentrations of heavy metals in streams across Baltimore, Maryland and within the context of convergent increases in salinity and organic carbon (two important variables that are known to affect metal transport in surface waters) due to urbanization. Despite past reductions of lead in gasoline and paints, mean concentrations of lead in some Baltimore streams were still approximately 75 micrograms/L and exceeded the U.S. EPA recommended criteria by 50 times. Mean concentrations of zinc and copper across Baltimore streams were also elevated and ranged between 15 to 140 micrograms/L and 2 to 40 micrograms/L, and mean concentrations of these metals were considerably higher than national means reported by the National Storm Water Quality database (NSWQ), which spans 3,770 storm events across the U.S. There were substantial increases in concentrations of heavy metals in streams during storms with greater than 80 percent, 70 percent, and 20 percent of storm samples exceeding recommended U.S. EPA metals criteria for Cu, Pb, and Zn respectively. Relationships between metal concentrations and stream discharge followed different patterns than nitrate and total phosphorus, other regulated pollutants in the Chesapeake Bay watershed, suggesting differences in sources and transport mechanisms within watersheds. Environmental factors such as increasing salinity from deicer use (with chloride concentrations in streams now ranging up to 5 g/L) may contribute to elevated transport of metals through ion exchange and mobilization of metals in soils and sediments. Environmental factors such as increasing organic carbon in urban streams, with ranges of 2 - 16 times greater in suburban and urban streams than forest watersheds, may also act as a vector for transporting metals due to binding capacity. Results show that metals appear to be present in harmful concentrations in many streams in Baltimore, Maryland, but further work is needed to elucidate shifts in the origin of metal pollution (storage in soils and sediments vs. roadway surfaces), and the effects of widespread changes in environmental factors that can potentially enhance their mobilization to streams.

Kaushal, S. S.; Belt, K. T.; Stack, W. P.; Pouyat, R. V.; Groffman, P. M.; F, S. E.

2006-05-01

67

Electrodialytic Removal of Heavy Metals from Different Solid Waste Products  

Microsoft Academic Search

A variety of heavy metal polluted waste products must be handled today. Electrochemical methods have been developed for remediation of polluted soil. One of the methods is the electrodialytic remediation method that is based on electromigration of heavy metal ions and ionic species within the soil matrix, and a separation of the soil and the process solutions, where the heavy

Lisbeth M. Ottosen; Iben V. Kristensen; Anne J. Pedersen; Henrik K. Hansen; Arne Villumsen; Alexandra B. Ribeiro

2003-01-01

68

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

69

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

70

Ion exchange extraction of heavy metals from wastewater sludges.  

PubMed

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

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

2004-01-01

71

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

72

Facultative hyperaccumulation of heavy metals and metalloids.  

PubMed

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

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

2014-03-01

73

Chemistry 330 / Study Guide 217 Toxic Heavy Metals  

E-print Network

and a light metal. 2. describe how most heavy metals are transported from place to place. Key Terms heavy poisoning assumes that most of the metal is still in the blood. In this case, chelation therapy: Chelation therapy carries a real risk. Organic ligands in the blood can potentially chelate and effectively

Short, Daniel

74

Heavy metal retention of different embankments  

NASA Astrophysics Data System (ADS)

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

Werkenthin, Moritz; Kluge, Bjoern; Wessolek, Gerd

2013-04-01

75

Heavy metal music and reckless behavior among adolescents.  

PubMed

Adolescents who liked heavy metal music were compared to those who did not on a variety of outcome variables, particularly focusing on reckless behavior. Boys who liked heavy metal music reported a higher rate of a wide range of reckless behavior, including driving behavior, sexual behavior, and drug use. They were also less satisfied with their family relationships. Girls who liked heavy metal music were more reckless in the areas of shoplifting, vandalism, sexual behavior, and drug use, and reported lower self-esteem. Both boys and girls who liked heavy metal music were higher in sensation seeking and more self-assured with regard to sexuality and dating. In regression analyses, the relation between reckless behavior and liking heavy metal music was sustained for five out of twelve variables concerning reckless behavior, including three of four among girls, when sensation seeking and family relationships were entered into the equation before liking or not liking heavy metal music. PMID:24263613

Arnett, J

1991-12-01

76

Reduction of heavy metal load in food chain: technology assessment  

Microsoft Academic Search

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

Anita Singh; Sheo Mohan Prasad

77

Heavy Metals Determination in Environmental and Biological Samples  

Microsoft Academic Search

\\u000a Heavy metals are present as elementary compounds or mineral deposits in nature, from which they are extracted and processed\\u000a for different purposes. During these processes, heavy metals are released in the environment and reach the atmosphere, waters,\\u000a soils, and biota (plants and animals). Heavy metals release into the environment is of great concern, due to their ability\\u000a to concentrate and

Camelia Draghici; Cristina Jelescu; Carmen Dima; Gheorghe Coman; Elisabeta Chirila

78

DISTRIBUTION OF HEAVY METALS IN CONTAMINATED RIVER SEDIMENT  

Microsoft Academic Search

Sediment was collected from the Ell-Ren River for analysis, to assess the influence of geochemical components in the sediment on remobilization of heavy metals into pore water and on distribution of each heavy metal in five geochemical phases (exchangeable, carbonates, Mn-oxides, Fe-oxides, and organic matters (OM)) in the sediment. Average distribution coefficients, the ratio of heavy metal in pore water

Li-Jyur Tsai; Kuang Chung Yu; Ju-Sheng Huang; Shien-Tsong Ho

2002-01-01

79

Removal of dissolved heavy metals and radionuclides by microbial spores  

SciTech Connect

Microbial systems have been shown to remove specific heavy metals from contaminated aqueous waste to levels acceptable to EPA for environmental release. However, systems capable of removing a variety of heavy metals from aqueous waste to environmentally acceptable levels remain to be reported. The present studies were performed to determine the specificity of spores of the bacterium Bacillus megaterium for the adsorption of dissolved metals and radionuclides from aqueous waste. The spores effectively adsorbed eight heavy metals from a prepared metal mix and from a plating rinse waste to EPA acceptable levels for waste water. These results suggest that spores have multiple binding sites for the adsorption of heavy metals. Spores were also effective in adsorbing the radionuclides {sup 85}strontium and {sup 197}cesium. The presence of multiple sites in spores for the adsorption of heavy metals and radionuclides makes this biosorbent a good candidate for the treatment of aqueous wastes associated with the plating and nuclear industries. 17 refs., 4 tabs.

Revis, N.W.; Hadden, C.T.; Edenborn, H. [and others

1997-11-01

80

Heavy metal atmospheric deposition and biomonitoring  

NASA Astrophysics Data System (ADS)

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

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

2003-05-01

81

Transport of heavy metals in process wastewaters  

SciTech Connect

Coal-conversion process wastewaters, obtained in the gasification and liquefaction of coal, generally contain appreciable quantities of toxic heavy metals and phenolic-type compounds in the aqueous phase which give rise to a substantial need for the study and elucidation of the complex ions formed in their interaction. Thus, these studies were undertaken to determine the extent of transport of these ions and/or their interaction products across the organic-aqueous phase and the characteristics of the interaction products. During the past year, the participants have been engaged in the systematic study of the transport and removal of the interaction products of several heavy metal ions, viz., Cu, Cd, Co, Fe, and Ni with selected coal tar phenols from aqueous media. These extraction studies were carried out using different liquid pairs such as dissopropyl ether-water and methyl iso-butyl ketone-water at various concentrations, ionic strengths, and pH's. More recently, the authors has standardized methods for carrying out these studies. Detailed transport of the transport of Cu, Fe, Zn, Pb, Cd and Ni resorcinol and/or catacohol complexes have been studied using polargraphy and HPLC Techniques. The polargraph was employed to ascertain the metal ion concentration and the HPLC was employed using electrochemical detection to determine the resorcinol or catecohol concentrations. The aqueous-organic extraction studies were generally carried out using iso-butyl ketone-water liquid-liquid pairs. These data indicate that after three successive extractions essential 100% of the phenolic complex agent is transported from the aqueous phase into the organic phase. 10 figs., 10 tabs.

Wilson, R.F.

1990-01-01

82

Toxic heavy metals: materials cycle optimization.  

PubMed

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

1992-02-01

83

Heavy liquid metal technologies development in Kalla  

SciTech Connect

The thermo-physical properties of Heavy Liquid Metals (Pb and Pb-Bi Eutectic) such as the low melting and high boiling temperatures, the chemical inertness in direct contact with typical reactor coolants, makes HLMs to relevant candidates as core coolant of critical and sub-critical nuclear systems. In addition the high neutron yield obtained by proton irradiation renders this material attractive for the development of neutron spallation sources. The practical use of HLM as core coolant and spallation material needs to be validated by experimental and computational activities. In this frame the KALLA (Karlsruhe Lead Laboratory) program, which consists of several stagnant and loop experiments, has been defined. Currently KALLA represents one of the most relevant infrastructures, which is in operation in Europe. The capabilities of KALLA make it possible to evaluate thermal-hydraulics parameters in complex geometries, to develop techniques for local and global quantities measurement, to assess the materials compatibility in different conditions and to evaluate basic chemical-physical data as for instance the wetting capability of the liquid metal. The aim of this article is to discuss the most significant development conducted at KALLA to support the activities of Accelerator Driven Transmutation Systems and to overview the experiences gained with the operation of liquid metal facilities. The loop experiments are now operated continuously since several years and a broad experience has been gained for the individual components typically appearing in reactors like pump systems (both electromagnetic and mechanical), oxygen monitoring and control systems, etc. (authors)

Stieglitz, Robert; Knebel, Joachim; Fazio, Concetta; Muller, Georg; Konys, Jurgen [Forschungszentrum Karlsruhe, Herrmann v. Helmholtz Platz 1, D-76344 Leopoldshafen (Germany)

2006-07-01

84

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

85

Bacteria that reduce content of heavy metals in plant  

US Patent & Trademark Office Database

This invention relates to bacteria having a function of reducing the content of heavy metals in plants, a method for reducing the content of heavy metals in plants with the use of such bacteria, and a composition comprising, as an active ingredient, such bacteria.

2013-02-26

86

Heavy metals in wild rice from northern Wisconsin  

Microsoft Academic Search

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

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

2000-01-01

87

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...

88

Permeable Reactive Biobarriers for the Containment of Heavy Metal  

E-print Network

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

Fay, Noah

89

Biosorption: An eco-friendly alternative for heavy metal removal  

Microsoft Academic Search

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

Srinivasa Reddy Ronda; Vijaya Saradhi Settalluri; Koneru Lakshmaiah

2007-01-01

90

Flow through luminescence for heavy metal analysis in seawater  

Microsoft Academic Search

The toxicity of heavy metals is well documented today and legislation for their control in seawater continuously becomes more and more restrictive. In order to control and ensure the marine environment quality it is demanded an effort to develop new analytical tools, which allow the analysis of trace levels of heavy metals in seawater. The measurement of luminescence (phosphorescence and

Blanca San Vicente De la Riva; Jose M. Costa Fernandez; Rosario Pereiro Garcia; Alfredo Sanz-Medel

1999-01-01

91

Heavy Metal Resistance of Biofilm and Planktonic Pseudomonas aeruginosa  

Microsoft Academic Search

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

Gail M. Teitzel; Matthew R. Parsek

2003-01-01

92

Broom fibre PRB for heavy metals groundwater remediation  

Microsoft Academic Search

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

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

2009-01-01

93

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

94

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

95

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

96

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

97

Heavy Metals Analysis and Sediment Quality Values in Urban Lakes  

Microsoft Academic Search

Problem statement: The objective of this research was to evaluate the degree of heavy metal contamination in lakes and the extent to whic h the sediment quality of the lakes of Bangalore city has deteriorated. Approach: In this study, heavy metals such as Cd, Co, Cu, Cr , Mn, Pb, Ni and Zn in lake bed sediments were analyzed using

Aboud S. Jumbe; N. Nandini

98

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

99

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

100

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

101

Heavy metal concentrations in roadside soils of Lithuania's highways  

NASA Astrophysics Data System (ADS)

With the number of vehicles increasing, the analysis of highway roadside soils for contamination by heavy metals becomes expedient. This article deals with contamination by heavy metals of the road-sides of the Vilnius-Kaunas-Klaip?da (A1), Vilnius-Panev?žys (A2), Vilnius-Var?na-Grodno (A4), Vilnius-Utena (A14) and Vilnius-Prienai-Marijampol? (A16) highways. The analysis covers six heavy metals - nickel (Ni), copper (Cu), chromium (Cr), lead (Pb), zinc (Zn), and manganese (Mn), - the contaminants most often emitted by vehicles. The results have shown the maximum permissible concentrations (MPC) of the heavy metals in question to be not exceeded in any of the samples, but the concentrations of some heavy metals in the highway roadsides exceeded the background concentrations 1.3 to 6.7 times.

Jankait?, Audron?; Baltr?nas, Pranas; Kazlauskien?, Agn?

2008-01-01

102

Fate and effects of heavy metals on the Arkansas river  

SciTech Connect

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

Clements, W.H.

1991-12-15

103

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

104

Biomedical implications of heavy metals induced imbalances in redox systems.  

PubMed

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

Sharma, Bechan; Singh, Shweta; Siddiqi, Nikhat J

2014-01-01

105

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

E-print Network

and the properties of the pore water in the mud may induce the release of some heavy metals into the mud. Field, but the heavy metals in the groundwater are in- creased. The release of heavy metals into pore water due the operationally determined chemical forms of five heavy metals (Cu, Ni, Pb, Zn, and Cd) in the mud samples. Heavy

Jiao, Jiu Jimmy

106

Bismuth film electrodes for heavy metals determination  

NASA Astrophysics Data System (ADS)

Bismuth film electrodes (BiFEs) have a potential to replace toxic mercury used most frequently for determination of heavy metals (Cd, Pb, Zn) by anodic stripping voltammetry. We prepared a graphite disc electrode (0.5 mm in diameter) from a pencil-lead rod and developed a nitrogen doped diamond-like carbon (NDLC) microelectrode array consisting of 50 625 microdiscs with 3 ?m in diameter and interelectrode distances of 20 ?m on a highly conductive silicon substrate as a support for BiFEs. The disc graphite BiFE was used for simultaneous determination of Pb(II), Cd(II) and Zn(II) by square wave voltammetry (SWV) in an aqueous solution. We found the optimum bismuth-to-metal concentration ratio in the solution to be 20. The dependence of the stripping responses on the concentration of target metals was linear in the range from 1×10 -8 to 1.2×10 -7 mol/L. Detection limits 2.4×10 -9 mol/L for Pb(II), 2.9×10 -9 mol/L for Cd(II) and 1.2×10 -8 mol/L for Zn(II) were estimated. A bismuth-plated NDLC microelectrode array was used for Pb(II) determination by differential pulse voltammetry (DPV) in an aqueous solution. We found that the stripping current for bismuth-plated NDLC array was linear in the concentration range of Pb(II) from 2×10 -8 to 1.2×10 -7 mol/L. The detection limit 2.2×10 -8 mol/L was estimated from a calibration plot.

Rehacek, Vlastimil; Hotovy, Ivan; Vojs, Marian; Mika, Fedor

2007-05-01

107

Kinetics of heavy-metal removal and recovery in sepiolite  

Microsoft Academic Search

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

M. F Brigatti; C Lugli; L Poppi

2000-01-01

108

Mechanochemical remediation of heavy metals contaminated soils: Modelling and experiments  

Microsoft Academic Search

The use of mechanochemistry for the remediation of heavy metals contaminated soils is investigated. Specifically, synthetic sandy soils contaminated by Cd(II), Pb(II) and Zn(II) are prepared. The degree of metal immobilization is evaluated after the soil is subjected to mechanical treatment by analyzing the leachable fraction of heavy metals obtained through the “synthetic precipitation leaching procedure (SPLP)”. For the case

Alessandro Concas; Selena Montinaro; Massimo Pisu; Giacomo Cao

2007-01-01

109

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

110

Biosorption of heavy metals by Saccharomyces cerevisiae: a review.  

PubMed

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 been researched during the past decades, Saccharomyces cerevisiae has received increasing attention due to the unique nature in spite of its mediocre capacity for metal uptake compared with other fungi. S. cerevisiae is widely used in food and beverage production, is easily cultivated using cheap media, is also a by-product in large quantity as a waste of the fermentation industry, and is easily manipulated at molecular level. The state of the art in the field of biosorption of heavy metals by S. cerevisiae not only in China, but also worldwide, is reviewed in this paper, based on a substantial number of relevant references published recently on the background of biosorption achievements and development. Characteristics of S. cerevisiae in heavy metal biosorption are extensively discussed. The yeast can be studied in various forms for different purposes. Metal-binding capacity for various heavy metals by S. cerevisiae under different conditions is compared. Lead and uranium, for instances, could be removed from dilute solutions more effectively in comparison with other metals. The yeast biosorption largely depends on parameters such as pH, the ratio of the initial metal ion and initial biomass concentration, culture conditions, presence of various ligands and competitive metal ions in solution and to a limited extent on temperature. An assessment of the isotherm equilibrium model, as well as kinetics was performed. The mechanisms of biosorption are understood only to a limited extent. Elucidation of the mechanism of metal uptake is a real challenge in the field of biosorption. Various mechanism assumptions of metal uptake by S. cerevisiae are summarized. PMID:16737792

Wang, Jianlong; Chen, Can

2006-01-01

111

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. Functionalized gold nanoparticles are aggregated in solution in the presence of divalent metal ions by an ion sufficiently intensely absorb- ing metal/dye complexes. Even the most intensely colored conventional molecular

112

Transport processes in heavy metal fluoride glasses  

NASA Astrophysics Data System (ADS)

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

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

2007-05-01

113

Heavy metal content of a medicinal moss tea for hypertension.  

PubMed

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

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

2012-01-01

114

Use of Electrodialysis to Remove Heavy Metals from Water  

Microsoft Academic Search

The removal of heavy metals from water by using electrodialysis is discussed. Parameters studied include current efficiency, stack resistance, and osmotic water transfer. Four single-electrolyte systems are investigated: CdCl2 and CdSO4 are used as representative heavy metal salts; NaCl and CaCl2 are studied in order to enhance the understanding of physical electrodialytic processes in general and to provide a basis

Kevin L. Gering; John F. Scamehorn

1988-01-01

115

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

116

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

117

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

118

Heavy metals emission from controlled combustion of PVC  

E-print Network

HEAVY METALS EMISSION FROM CONTROLLED COMBUSTION OF PVC A Thesis by MOHAMMED A. EL-AYYOUBI Submitted to the Office of Graduate Studies of Texas Ag M University in partial fulfillment of the requirement for the degas ee of' MASTER OF SCIENCE... August 1989 Major Subject: Safety Engineering HEAVY METALS EMISSION FROM CONTROLLED COMBUSTION OF PVC A Thesis by MOHAMMED A. EL-AYYOUBI Approved as to style and content by: John P. Wa r Chair of Committee) Waymo . Johnston (Member) Cesar...

El-Ayyoubi, Mohammed A.

2012-06-07

119

Evaluation of a microplate assay specific for heavy metal toxicity  

Microsoft Academic Search

A rapid, quantitative microbial assay, which is specific for heavy metal toxicity, has been developed. The assay (MetPLATE™) is in a 96-well microtitration plate format and is suitable for determining toxicity characteristics such as median inhibitory concentrations. The sensitivity of MetPLATE™ to heavy metals [Cu, Zn, Cd, Pb, Hg, Cr(III)] was generally higher than Microtox and was of the same

G. Bitton; K. Jung; B. Koopman

1994-01-01

120

Crab shell for the removal of heavy metals from aqueous solution  

Microsoft Academic Search

The ability of crab shell to remove heavy metals from aqueous solution was evaluated by comparing with that of several sorbents (cation exchange resin, zeolite, granular activated carbon, powdered activated carbon). All experiments were conducted using several heavy metal ion solutions (Pb, Cd, Cu, Cr). The orders of heavy metal removal capacity and initial heavy metal removal rate were found

H. K An; B. Y Park; D. S Kim

2001-01-01

121

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

Microsoft Academic Search

Wastewaters containing heavy metals are usually treated by chemical precipitation method in Taiwan. This method can remove heavy metals form wastewaters efficiently, but the resultant heavy metal sludge is classified as hazardous solid waste and becomes another environmental problem. If we can remove heavy metals from sludge, it becomes non-hazardous waste and the treatment cost can be greatly reduced. This

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

2006-01-01

122

Micellar-enhanced ultrafiltration of heavy metals using lecithin  

SciTech Connect

Conventional treatment methods for removal of heavy metals from metal finishing operations are usually energy-intensive and costly. Micellar-enhanced ultrafiltration (MEUF) with synthetic surfactants is a recently developed technique which can remove heavy metals and other small molecular weight ions from wastestreams at relatively lower costs and without a phase change. Lecithin, a natural, inexpensive, nontoxic, and biodegradable surfactant exhibits emulsifying characteristics which can be used in a MEUF. The binding of various lecithins to cadmium, copper, lead, nickel, and zinc - in a mixture and individually - was studied using a continuous diafiltration method. This technique uses small volumes of toxic waters and produces an entire isotherm with just one experiment. In the presence of all five heavy metals, the lecithin in this study showed the following affinity: Cu > Cd [approximately] Zn > Ni. In experiments when only one metal was present, lecithin exhibited the following affinity: Ni > Cu [approximately] Zn > Cd. Lead was not bound significantly in either scenario.

Ahmadi, S.; Tseng, L.K.; Batchelor, B.; Koseoglu, S.S. (Texas A M Univ., College Station, TX (United States))

1994-12-01

123

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

124

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

125

Review of heavy metals in the African aquatic environment.  

PubMed

Data were compiled from selected heavy metal studies in both freshwater and marine ecosystems from the major African subregions, Northern, West and Central, Eastern, and Southern Africa. The concentrations of heavy metals were compared between different environmental compartments (water, sediments, fauna, and flora), between the different African subregions and with data from other areas in the world. Despite the scarcity of the existing information on Africa, some conclusions could be drawn: Metal concentrations in organisms were generally below WHO limits except for some localized sites, mostly with increased lead levels. There were no significant differences between inland water and coastal animals, but shellfish had higher concentrations of most metals than finfish. For aquatic plants the heavy metal levels were higher in inland waters. Compared to more industrialized regions and with the exception of some hot-spot sites, the concentrations of heavy metals in African aquatic systems were low and close to natural background levels. Nevertheless, in view of the expected increase in urbanization and socio-economic activities in Africa, sources and quantities of heavy metal discharges to aquatic environments have to be identified. Also, pollution control measures should be formulated in each country. PMID:7525211

Biney, C; Amuzu, A T; Calamari, D; Kaba, N; Mbome, I L; Naeve, H; Ochumba, P B; Osibanjo, O; Radegonde, V; Saad, M A

1994-07-01

126

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

127

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...

128

Leaching of heavy metals from contaminated soils using EDTA  

Microsoft Academic Search

Ethylenediaminetetraacetic acid (EDTA) extraction of Zn, Cd, Cu and Pb from four contaminated soils was studied using batch and column leaching experiments. In the batch experiment, the heavy metals extracted were virtually all as 1:1 metal-EDTA complexes. The ratios of Zn, Cd, Cu and Pb of the extracted were similar to those in the soils, suggesting that EDTA extracted the

B Sun; F. J Zhao; E Lombi; S. P McGrath

2001-01-01

129

Bacterial resistance mechanisms for heavy metals of environmental concern  

Microsoft Academic Search

Summary Bacterial species have genetically-determined systems for resistances to toxic heavy metals. Those for metals of environmental concern including mercury cadmium, arsenic and others are briefly summarized, considering the genes of the systems and the biochemical mechanisms by which the resistance proteins function.

Guangyong Ji; Simon Silver

1995-01-01

130

Nematodes as bioindicators of soil degradation due to heavy metals.  

PubMed

The effect of distance from a heavy metal pollution source on the soil nematode community was investigated on four sampling sites along an 4 km transect originating at the Kovohuty a.s. Krompachy (pollution source). The soil nematode communities were exposed to heavy metal influence directly and through soil properties changes. We quantified the relative effects of total and mobile fraction of metals (As, Cd, Cr, Cu, Pb, and Zn) on soil ecosystem using the nematode community structure (trophic and c-p groups,) and ecological indices (Richness of genera, H', MI2-5, etc.). Pollution effects on the community structure of soil free living nematodes was found to be the highest near the pollution source, with relatively low population density and domination of insensitive taxa. A decrease in heavy metals contents along the transect was linked with an increase in complexity of nematode community. The majority of used indices (MI2-5, SI, H') negatively correlated (P < 0.05 or P < 0.01) with heavy metals content and were sensitive to soil ecosystem disturbance. Contamination by heavy metals has negatively affected the soil environment, which resulted in nematode community structure and ecological indices changes. Results showed that the free-living nematodes are useful tools for bioindication of contamination and could be used as an alternative to the common approaches based on chemical methods. PMID:22923372

Šalamún, Peter; Ren?o, Marek; Kucanová, Eva; Brázová, Tímea; Papajová, Ingrid; Miklisová, Dana; Hanzelová, Vladimíra

2012-11-01

131

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

132

Heavy metals in a stream ecosystem at sites near highways  

SciTech Connect

Water, sediment, benthos, and fish samples from Back Creek, a soft-water stream in southwestern Virginia, were analyzed to determine whether highway proximity and traffic density influence heavy metal content. Concentrations of lead, zinc, nickel, and cadmium were low in streamwater samples collected from three sites adjacent to highways of low moderate traffic volumes. Sediment concentrations of these metals correlated significantly with traffic density, as did whole body concentrations in benthic insects and fish. Seasonal variation in heavy metal content was evident only in sediment. Long-term field investigations of community dynamics are recommended as a means of assaying the threat to aquatic ecosystems posed by highway-generated heavy metal contamination.

Van Hassel, J.H.; Ney, J.J.; Garling, D.L.

1980-11-01

133

Molecular Indicators of Soil Humification and Interaction with Heavy Metals  

SciTech Connect

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

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

2003-03-26

134

Implications of soil pollution with heavy metals for public health  

NASA Astrophysics Data System (ADS)

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

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

2008-01-01

135

The environmental impact of gold mines: pollution by heavy metals  

NASA Astrophysics Data System (ADS)

The gold mining plant of Oman was studied to assess the contribution of gold mining on the degree of heavy metals into different environmental media. Samples were collected from the gold mining plant area in tailings, stream waters, soils and crop plants. The collected samples were analyzed for 13 heavy metals including vanadium (V), chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), cadmium (Cd), cobalt (Co), lead (Pb), zinc (Zn), aluminium (Al), strontium (Sr), iron (Fe) and barium (Ba). The water in the acid evaporation pond showed a high concentration of Fe as well as residual quantities of Zn, V, and Al, whereas water from the citizens well showed concentrations of Al above those of Omani and WHO standards. The desert plant species growing closed to the gold pit indicated high concentrations of heavy metals (Mn, Al, Ni, Fe, Cr, and V), while the similar plant species used as a control indicated lesser concentrations of all heavy metals. The surface water (blue) indicated very high concentrations of copper and significant concentrations of Mn, Ni, Al, Fe, Zn, lead, Co and Cd. The results revealed that some of the toxic metals absorbed by plants indicated significant metal immobilization.

Abdul-Wahab, Sabah Ahmed; Marikar, Fouzul Ameer

2012-06-01

136

Beneficial effect of sesame oil on heavy metal toxicity.  

PubMed

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

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

2014-02-01

137

Heavy metal pollution in coastal areas of South China: a review.  

PubMed

Coastal areas of South China face great challenges due to heavy metal contamination caused by rapid urbanization and industrialization. In this paper, more than 90 articles on levels, distributions, and sources of heavy metals in sediments and organisms were collected to review the status of heavy metal pollution along coastal regions of South China. The results show that heavy metal levels were closely associated with local economic development. Hong Kong and the Pearl River Estuary were severely contaminated by heavy metals. However, concentrations of heavy metals in sediments from Hong Kong have continually decreased since the early 1990 s. High levels of heavy metals were found in biota from Lingdingyang in Guangdong province. Mollusks had higher concentrations of heavy metals than other species. Human health risk assessments suggested that levels of heavy metals in some seafood from coastal areas of South China exceeded the safety limit. PMID:24084375

Wang, Shuai-Long; Xu, Xiang-Rong; Sun, Yu-Xin; Liu, Jin-Ling; Li, Hua-Bin

2013-11-15

138

Evaluation of Different Extraction Methods for the Assessment of Heavy Metal Bioavailability in Various Soils  

Microsoft Academic Search

The main objective of this study was to compare the effectiveness of different methods (heavy metals in pore water (PW), diffusive\\u000a gradients in thin films (DGT), diethylene triamine pentaacetic acid (DTPA) extraction, and total heavy metals (THM) in soil)\\u000a for the assessment of heavy metal bioavailability from soils having various properties and heavy metal contents. The effect\\u000a of soil heavy

José Martin Soriano-Disla; Tom W. Speir; Ignacio Gómez; Lynne M. Clucas; Ron G. McLaren; José Navarro-Pedreño

2010-01-01

139

In vitro susceptibility of spiroplasmas to heavy-metal salts.  

PubMed Central

The susceptibility of six spiroplasma strains to heavy-metal salt was characterized in terms of minimal inhibitory concentrations and minimal biocidal concentrations in broth tube dilution tests. The strains were most susceptible to mercuric chloride and silver nitrate; less susceptible to copper sulfate, cobalt chloride, lead nitrate, and cadmium sulfate; and least susceptible to nickel chloride and zinc sulfate. Spiroplasma citri strains Maroc R8A2 and C189 were the most susceptible to five of eight heavy-metal salts, and honeybee spiroplasma strain AS576 and Spiroplasma floricola strain 23-6 were generally the least susceptible. The difference between the minimal biocidal concentrations and the minimal inhibitory concentrations was greater for certain heavy-metal salts than for others. PMID:6830208

Whitmore, S C; Rissler, J F; Davis, R E

1983-01-01

140

Heavy metal content of black teas consumed in Iran.  

PubMed

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

Falahi, Ebrahim; Hedaiati, Roshanak

2013-01-01

141

Trace organic and heavy metal pollutants in the Mississippi River  

SciTech Connect

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

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

1986-01-01

142

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

SciTech Connect

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

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

1994-08-01

143

Oil palm biomass as an adsorbent for heavy metals.  

PubMed

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

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

2014-01-01

144

A simple and versatile PSA system for heavy metal determinations.  

PubMed

An easy to build potentiometric stripping analysis system for heavy metal determinations (Zn, Cd, Pb, Cu) is described which reaches good sensitivity and precision. Main components are an IBM compatible computer, an ADDA-conversion card and two selfmade electrodes, so it can be realized for one tenth of the price of complete commercial systems. A graphite pencil lead covered with a Hg-film is used as working electrode and a Ag/AgCl electrode as a combined reference/counter electrode. Reproducibility and calibration measurements are reported, heavy metal determinations on soil samples are compared with AAS results. PMID:15045254

Bund, A; Dittmann, J; Lordkipanidze, D; Schwitzgebel, G

1996-08-01

145

[Hyperspectral remote sensing in monitoring the vegetation heavy metal pollution].  

PubMed

Mine exploitation aggravates the environment pollution. The large amount of heavy metal element in the drainage of slag from the mine pollutes the soil seriously, doing harm to the vegetation growing and human health. The investigation of mining environment pollution is urgent, in which remote sensing, as a new technique, helps a lot. In the present paper, copper mine in Dexing was selected as the study area and China sumac as the study plant. Samples and spectral data in field were gathered and analyzed in lab. The regression model from spectral characteristics for heavy metal content was built, and the feasibility of hyperspectral remote sensing in environment pollution monitoring was testified. PMID:21105429

Li, Na; Lü, Jian-sheng; Altemann, W

2010-09-01

146

Resistance to heavy metals by some Nigerian yeast strains.  

PubMed

The heavy metal resistance of yeasts isolated from sugary substrates such as orange, palm wine and pineapple and identified as Saccharomyces carlsbergensis and S. cerevisiae was studied. The yeast isolates were tested against different concentrations of cadmium, copper, manganese, silver and zinc salts ranging from 1 to 20 mmol/L. Local yeasts showed resistance to 3-15 mmol/L cadmium, 18-20 copper, 16-20 manganese, 1-9 silver and 16-19 for zinc. The significance of the results is discussed in relation to the effects of heavy metals on growth of microorganisms and selection of yeasts for the brewing industry in Nigeria. PMID:8112693

Olasupo, N A; Scott-Emuakpor, M B; Ogunshola, R A

1993-01-01

147

Heavy Metals in Blue Mussels ( Mytilus edulis ) in the Bergen Harbor Area, Western Norway  

Microsoft Academic Search

Heavy metal discharges to the marine environment are of great concern all over the world. Both essential (e.g., Fe, Zn, Cu) and non essential (e.g., Hg, Cd, Pb) metals are toxic to living organism when subjected to high concentration. Many heavy metals accumulate in organisms and some also accumulate in the food chain. The anthropogenic heavy metal outlets can in

V. Andersen; A. Maage; P. J. Johannessen

1996-01-01

148

Toxicity assessment of heavy metal mixtures by Lemna minor L.  

PubMed

The discharge of untreated electroplating wastewaters directly into the environment is a certain source of heavy metals in surface waters. Even though heavy metal discharge is regulated by environmental laws many small-scale electroplating facilities do not apply adequate protective measures. Electroplating wastewaters contain large amounts of various heavy metals (the composition depending on the facility) and the pH value often bellow 2. Such pollution diminishes the biodiversity of aquatic ecosystems and also endangers human health. The aim of our study was to observe/measure the toxic effects induced by a mixture of seven heavy metals on a bioindicator species Lemna minor L. Since artificial laboratory metal mixtures cannot entirely predict behaviour of metal mixtures nor provide us with informations relating to the specific conditions in the realistic environment we have used an actual electroplating wastewater sample discharged from a small electroplating facility. In order to obtain three more samples with the same composition of heavy metals but at different concentrations, the original electroplating wastewater sample has undergone a purification process. The purification process used was developed by Orescanin et al. [Orescanin V, Mikeli? L, Luli? S, Nad K, Rubci? M, Pavlovi? G. Purification of electroplating wastewaters utilizing waste by-product ferrous sulphate and wood fly ash. J Environ Sci Health A 2004; 39 (9): 2437-2446.] in order to remove the heavy metals and adjust the pH value to acceptable values for discharge into the environment. Studies involving plants and multielemental waters are very rare because of the difficulty in explaining interactions of the combined toxicities. Regardless of the complexity in interpretation, Lemna bioassay can be efficiently used to assess combined effects of multimetal samples. Such realistic samples should not be avoided because they can provide us with a wide range of information which can help explain many different interactions of metals on plant growth and metabolism. In this study we have primarily evaluated classical toxicity endpoints (relative growth rate, Nfronds/Ncolonies ratio, dry to fresh weight ratio and frond area) and measured guaiacol peroxidase (GPX) activity as early indicator of oxidative stress. Also, we have measured metal accumulation in plants treated with waste ash water sample with EDXRF analysis and have used toxic unit (TU) approach to predict which metal will contribute the most to the general toxicity of the tested samples. PMID:17610935

Horvat, Tea; Vidakovi?-Cifrek, Zeljka; Orescanin, Visnja; Tkalec, Mirta; Pevalek-Kozlina, Branka

2007-10-01

149

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

150

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

PubMed

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

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

2014-01-30

151

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

152

Phytoremediation of heavy metal contaminated soil by Jatropha curcas.  

PubMed

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

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

2014-12-01

153

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

154

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... Subject: Wildlife and Fisheries Sciences PESTICIDE AND HFAVY METAL RFSIDUFS IN LOUISIANA RIVER OTTFR A Thesis by DFBRA LYNN BECK Approved as to style and con ent by: (Chairman of Committee) ~ -ne U (Head of Department) (Member) (Member) May 1977...

Beck, Debra Lynn

2012-06-07

155

Treatment and minimization of heavy metal-containing wastes 1995  

Microsoft Academic Search

This symposium was held in conjunction with the 1995 Annual Meeting of the Minerals, Metals and Materials Society in Las Vegas, Nevada, February 12--16, 1995. The purpose of this meeting was to provide a forum for exchange of state-of-the-art information on treating and minimizing heavy metal-containing wastes. Papers were categorized under the following broad headings: aqueous processing; waste water treatment;

J. P. Hager; B. Mishra; C. F. Davidson; J. L. Litz

1995-01-01

156

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

157

Chromate reduction and heavy metal fixation in soil. Final report  

Microsoft Academic Search

In situ reduction of chromates and the fixation of the metals Cr, Pb, Zn, Cu, Cd and Ni in soil was investigated using Fe II and soluble silica. Fe II fulfills two functions. It reduces chromates (CrVI) at soil pH to CrIII and the reaction products, Fe(OH)â and Cr(OH)â, coprecipitate\\/adsorb heavy metals. In the absence of CrVI iron is added

Schwitzgebel

1992-01-01

158

Chromate reduction and heavy metal fixation in soil  

Microsoft Academic Search

In situ reduction of chromates and the fixation of the metals Cr, Pb, Zn, Cu, Cd and Ni in soil was investigated using Fe II and soluble silica. Fe II fulfills two functions. It reduces chromates (CrVI) at soil pH to CrIII and the reaction products, Fe(OH)[sub 3] and Cr(OH)[sub 3], coprecipitate\\/adsorb heavy metals. In the absence of CrVI iron

Schwitzgebel

1992-01-01

159

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

160

Heavy metal-activated synthesis of peptides in Chlamydomonas reinhardtii  

Microsoft Academic Search

In this study, the authors have addressed the capacity of the green alga Chlamydomonas reinhardtii to produce metal-binding peptides in response to stress induced by the heavy metals Cd{sup 2+}, Hg{sup 2+}, and Ag{sup +}. Cells cultured in the presence of sublethal concentrations of Cd{sup 2+} synthesized and accumulated oligopeptides consisting solely of glutamic acid, cysteine, and glycine in an

G. Howe; S. Merchant

1992-01-01

161

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

162

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

163

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

164

Influence of heavy metals on soil microbial activities  

Microsoft Academic Search

Studies were carried out to evaluate the influence of Cd, Cr, Cu, Ni, Pb, or Zn on the decomposition of organic matter in soils and on their microflora. The heavy metals were added to samples of Gley soil and Light-colored Andosol at the level of 10 ?mol\\/g soil, respectively. Three days after the addition, sewage sludge was mixed with the

Hiroyuki Hattori

1992-01-01

165

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

NASA Astrophysics Data System (ADS)

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

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

2011-07-01

166

Heavy metal history from cores in Wellington Harbour, New Zealand  

Microsoft Academic Search

Analysis of ten heavy metals (Ag, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Zn) in six sediment cores from Wellington Harbour show both anthropogenic enrichments and diagenetic modifications. Absolute concentrations determined by two methods, x-ray fluorescence and acid leaching for bioavailability, are not comparable. However, vertical trends in concentrations of the cored sediment are comparable. To assess levels of

W. W. Dickinson; G. B. Dunbar; H. McLeod

1996-01-01

167

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

168

Tons of Heavy Metals in Mill Creek Sediments Heather Freeman  

E-print Network

time the sewers overflow, a mixture of raw sewage and storm water goes directly into the Mill Creek. My objectives for this summer research were to: 1.) determine how much heavy metal pollution has accumulated in the Mill Creek sediments, and 2.) whether there is a change over time in the amount of pollution

Maynard, J. Barry

169

Heavy Metal Tolerance Robert S. Boyd, Nishanta Rajakaruna  

E-print Network

have severe impacts on the health of humans, other organisms, and entire ecosystems. Current studies (DNA or RNA) in cells. Some organisms are less susceptible to these effects than others, and this heavy metal tolerance also has vital practical and applied aspects, since human industry relies greatly

Rajakaruna, Nishanta

170

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

171

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

172

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

173

Mutagenic activity of heavy metals in soils of wayside slopes  

Microsoft Academic Search

The genotoxic properties of soils polluted with heavy metals were studied on two wayside slopes covered with trees in the city of Voronezh. The nucleolar test in cells of the apical meristem of Zebrina pendula Schnizl. roots was used. The genotoxic effect of the soils was revealed according to the increased number of 2-and 3-nucleolar cells (from 41 to 54%

A. I. Fedorova; V. N. Kalaev; Yu. G. Prosvirina; S. A. Goryainova

2007-01-01

174

Heavy Metal Levels in Fish from Coastal Waters of Uruguay  

Microsoft Academic Search

Copper, mercury, and zinc levels were determined in muscle and liver (N?=?163) of seven fish species caught in coastal waters off Montevideo and Piriápolis (control site): Odontesthes spp., Mugil platanus, Micropogonias furnieri, Urophycis brasiliensis, Cynoscion guatucupa, Menticirrhus americanus, and Mustelus schmitti. The local population commonly uses these species for consumption. Heavy metal concentrations determined in this study were generally below

F. Viana; R. Huertas; E. Danulat

2005-01-01

175

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

176

Heavy metals pollution in the environment of Kathmandu  

NASA Astrophysics Data System (ADS)

Nepal situated on the lap of mighty Himalayas is now threatened by heavy metals pollution in her atmosphere, land and river system. The indigenious technology of Nepal heavily depends on the use of mercury in gold plating technique. The mercury vapours are released to the atmosphere, when gold-amalgam smeared untesils and idols are strongly heated. Absence of control mechanism to collect mercury vapours has not only polluted atmosphere but it has also caused health hazard to the workers working in the poorly ventilated workshop. The craftsmen and articians have been victim of mercury poisoining. Another heavy metal that has caused atmospheric pollution in Nepal is lead. The lead containing gasoline used in greater amount in vehicles has released more and more lead in the from of exhaust gas into the atmosphere. The atmospheric pollution has been more acute in Nepal due to the use of lead gasoline in used vehicles. Likewise the river system of the urban areas of Nepal is polluted by heavy metals like cadmium, lead salt, ferrous salt, etc. The effulents of battery industries, leather factories, dye factories are directly dumped into the river system of urban areas. This has killed many aquatic animals of rivers. Thus Nepal is facing the problem of heavy metals pollution in her environnent.

Shrestha, H. D.

2003-05-01

177

Heavy metals pollution in the environment of Kathmandu  

Microsoft Academic Search

Nepal situated on the lap of mighty Himalayas is now threatened by heavy metals pollution in her atmosphere, land and river system. The indigenious technology of Nepal heavily depends on the use of mercury in gold plating technique. The mercury vapours are released to the atmosphere, when gold-amalgam smeared untesils and idols are strongly heated. Absence of control mechanism to

H. D. Shrestha

2003-01-01

178

DEVELOPMENT OF POLAROGRAPHIC SENSORS FOR HEAVY METAL DETECTION SENSING APPLICATIONS  

Microsoft Academic Search

Field sensors offer potential improvements over laboratory-based methods for heavy metal analysis because concentration assays of environmental specimens are more rapidly obtained. This allows easier pollution hot spot detection and minimizes artifacts caused by sample transport and storage. This research project involves a field sensor concept based on polarographic techniques. Polarography is an electroanalytical method that performs trace level analysis

K. J. Bundy; D. Berzins; P. Taverna

179

Accumulation of heavy metals by freshwater zooplankton - a toxicological study  

Microsoft Academic Search

So far many toxicologic studies are made earlier; we studied the acute toxicity estimation related to some specific identified freshwater zooplanktons of Paradip (Harbour City) area of Jagatsingpur District, Orissa, India which is situated on the bank of Mahanadi River. The study area is prone to heavy metal pollution because mineral based industries in relation to zinc, lead and cadmium

S. K. Baliarsingh; S. Srichandan; T. Padmavati; Subrat Naik; K. C. Sahu

2010-01-01

180

Heavy metal analysis of groundwater from Warri, Nigeria  

Microsoft Academic Search

The levels of some ions of heavy metals known to be associated with petroleum industry operations, including Pb, Ni, V, Cr, Cd, Zn and Fe, were studied in untreated groundwater from Warri area, Nigeria, by atomic absorption spectroscopy. Warri area is characterized by petroleum industry activities including a Refinery. With this in mind, the residential area was divided into Effurun

David A. Aremu; Joshua F. Olawuyi; Shunsuke Meshitsuka; Mynepalli K. Sridhar; Paul A. Oluwande

2002-01-01

181

Atomic Absorption Spectrophotometry Simplifies Heavy-Metals Analysis  

Microsoft Academic Search

Personnel of the Water Purification Lab. of Chicago conclude that the use of atomic absorption is superior to that of wet chemistry for the analysis of heavy metals. The authors present the basic operating principles, procedures for adjusting the instrument settings, and precautions concerning operation—if problems are to be avoided.

Benjamin F. Willey; Carlton M. Duke; Ann L. Wojciesiak; Cherryl T. Thomas

1972-01-01

182

Forecast Estimation of Heavy Metals Values in a Soils  

Microsoft Academic Search

Recently problem of accumulation of heavy metals in an atmosphere, soils both waters in the natural and antropogently-modified landscapes is characteristic for many countries of the world. The soil can be considered as the integrated indicator of long-term process of pollution of an environment giving representation about quality of environments connected with soil - air and waters. The influence of

T. Koroleva

183

A clean laboratory for ultralow concentration heavy metal analysis  

Microsoft Academic Search

Laboratory facilities and methods are described which have been developed in our laboratory in collaboration with C. Patterson's group at the California Institute of Technology for the reliable measurement of various heavy metals at extremely low concentration levels down to the sub pg\\/g level in Antarctic and Greenland snow and ice. All analytical work is performed inside a clean laboratory

Claude F. Boutron

1990-01-01

184

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

185

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

186

HEAVY METAL CONTAMINATION IN THE TAIMYR PENINSULA, SIBERIAN ARCTIC  

EPA Science Inventory

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

187

Contribution of Sulfonate Groups and Alginate to Heavy Metal  

E-print Network

of Sargassum fluitans E R I C F O U R E S T A N D B O H U M I L V O L E S K Y * Department of Chemical of heavy metal complexation by the dry biomass of the brown seaweed Sargassum fluitans was investigated metalrecovery. ThebrownseaweedofthegenusSargassum was previously selected for its capacity to bind selectively

Volesky, Bohumil

188

Heavy Metals in Epiphytic Mosses: An Experience in Florence  

Microsoft Academic Search

The epiphytic moss Hypnum cupressiforme has been used for passive monitoring of airborne heavy metals pollution by vehicular traffic in the urban area of Florence. Lead, cadmium, zinc and copper were determined by differential pulse anodic stripping voltammetry (DPASV). in the summer of 1993 about 30 samples were collected from the trunks of holm oak at the same height (1

Paola Cellini Legittimo; Roberta Benvenuti

1996-01-01

189

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

Microsoft Academic Search

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

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

1994-01-01

190

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

191

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

192

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

193

Heavy Metal Tolerance in Stenotrophomonas maltophilia  

PubMed Central

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

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

2008-01-01

194

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, ...

195

A Hydroponic Study of Heavy Metal Uptake by Selected Marsh Plant Species.  

National Technical Information Service (NTIS)

Eight marsh plants were grown in chemically controlled hydroponic solutions containing three concentrations of heavy metals to evluate the ability of each plant species to take up and accumulate heavy metals. The marsh plants studies were Cyperus esculent...

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

1976-01-01

196

A sensitive rapid on-site immunoassay for heavy metal contamination  

SciTech Connect

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

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

1996-05-02

197

Spectroscopic investigations of heavy metal binding to biomaterials  

SciTech Connect

The application of biomaterials for the binding of heavy metals from contaminated waters has many attractive features. Among these are their relative low costs, their natural selectivity relative to more benign metals, and their high binding capacities. Unfortunately, a general lack of understanding of the fundamental chemical interaction responsible for the binding of heavy metals by these materials response has often restricted their use to systems with comparatively well defined influent composition. To enable these materials to be used to their fullest capability, it will be necessary to acquire such a fundamental understanding of these basic chemical processes. In this paper, work in our laboratory pertaining to the investigation of heavy metal binding to biomaterials will be discussed. Specifically, materials composed of cell wall fragments from the plant Datura innoxia and a fraction of organic peat have been investigated using several spectroscopic techniques. The techniques which will be discussed include solid-state luminescence of bound lanthanide ions, {sup 113}Cd-NMR (slurries and solid-state), and solid-state FT-IR. The findings of these investigations regarding the binding of metal ions to each of these materials and the impact of solution conditions (e.g., pH) will be discussed.

Rayson, G.D.; Drake, L.R. [New Mexico State Univ., Las Cruces, NM (United States)

1995-12-31

198

Removal of heavy metals by hybrid electrocoagulation and microfiltration processes.  

PubMed

This study is based on the investigation of the performance of electrocoagulation (EC), followed by the microfiltration process for heavy metal removal in synthetic model waste water containing Zn2+, Ni2+ and Cd2+ ions. Effects of initial concentration, current density and pH on metal removal were analysed to optimize the EC process. The optimized EC process was then integrated with dead-end microfiltration (MF) and was found that the hybrid process was capable of 99% removal of heavy metals. The cake layer formed over the membrane by the hybrid process was analysed through scanning electron microscope-energy-dispersive X-ray spectroscopy. The particle size analysis of the sludge formed during EC was done to investigate the fouling caused during the process. PMID:24527655

Keerthi; Vinduja, V; Balasubramanian, N

2013-01-01

199

Sorption of heavy metals by Lithuanian glauconite  

Microsoft Academic Search

Adsorption equilibria are evaluated for Cd(II), Pb(II) and Zn(II) on a sample of pass 200 mesh Lithuanian glauconite using two different experimental\\/analytical approaches. First, the impacts of total metal concentration, ionic strength and pH on adsorption capacity are quantified in terms of the Freundlich isotherm equation for isotherms conducted at a single initial pH value. Relative adsorption capacity for the

Edward H. Smith; Weiping Lu; Tomas Vengris; Rima Binkiene

1996-01-01

200

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

201

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

202

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

203

A heavy metal biossay based on percent spore germination of the sensitive fern, Onoclea sensibilis  

Microsoft Academic Search

This is the first in a series of reports on the effects of heavy metals on the fern gametophyte developmental system. We report herein on a heavy metal bloassay based on percent fern spore germination. We selected two of the top three heavy metal pollutants -- mercury and cadmium -- for investigation and deleted lead because of its low solubility.

Raymond L. Petersen; Damon Arnold; David G. Lynch; Steven A. Price

1980-01-01

204

Ecotoxicological Studies. 3. Heavy metals contaminating water and fish from Fayoum Governorate, Egypt  

Microsoft Academic Search

The distribution of some heavy metals in water and fish from Fayoum Governorate (Egypt) was studied in samples collected throughout two successive years (1997\\/1998 and 1998\\/1999). Water from Lake Qarun, a private fish farm and “Sanhour River” was found to contain heavy metals at concentration levels lower than those found in fish from the first two ecosystems. The heavy metals

S. A. Mansour; M. M. Sidky

2002-01-01

205

Studies on potential applications of biomass for the separation of heavy metals from water and wastewater  

Microsoft Academic Search

Heavy metal pollution has become a more serious environmental problem in the last several decades as a result of its toxicity and insusceptibility to the environment. This paper attempts to present a brief summary of the role of biomass in heavy metal removal from aqueous solutions. Undoubtedly, the biosorption process is a potential technique for heavy metal decontamination. The current

Sisca O. Lesmana; Novie Febriana; Felycia E. Soetaredjo; Jaka Sunarso; Suryadi Ismadji

2009-01-01

206

Evaluating heavy metal contents in nine composts using four digestion methods  

Microsoft Academic Search

The production and application of compost potentially contaminate the environment with heavy metals. The heavy metal contents of composts must be exactly determined. Therefore, this study aims to understand the heavy metal contents in composts, using different digestion methods and to recommend the most appropriate digestion method making this measurement. Nine composts from different sources, including swine manure, poultry litter,

Zeng-Yei Hseu

2004-01-01

207

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

Microsoft Academic Search

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

S Topcuo?lu; Ç K?rba?o?lu; N Güngör

2002-01-01

208

Investigations of Toxic and Genotoxic Effects of Heavy Metals and their Model Mixture on Plants  

Microsoft Academic Search

In the recent investigations of environment pollution, in order to determine toxic effects of industrial sewage, herbicides, and heavy metals, higher plants are more commonly investigated. Toxic and genotoxic effects of separate heavy metals and their mixtures on plants – test-organisms have been investigated. Concentrations of heavy metals that were found in the studied mixture were taken into account. Besides,

Danguol? Montvydien?; R?ta Laka?auskien?; Danut? Mar?iulionien?

1999-01-01

209

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

210

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

211

Release of heavy metals during weathering of the Lower Cambrian Black Shales in western Hunan, China  

Microsoft Academic Search

Weathering of heavy metal enriched black shales may be one of the most important sources of environmental contamination in areas where black shales are distributed. Heavy metal release during weathering of the Lower Cambrian Black Shales (LCBS) in western Hunan, China, was investigated using traditional geochemical methods and the ICP-MS analytical technique. Concentrations of 16 heavy metals, 8 trace elements

Bo Peng; Zhaoliang Song; Xiangling Tu; Meilian Xiao; Fucheng Wu; Huanzhe Lv

2004-01-01

212

Study on Form Distribution and Correlation of Heavy Metals in the Sediment of Urban Water  

Microsoft Academic Search

With the Tessier Five-step Continuous Extracting Method, the thesis studied the form distribution of heavy metals in the sediment samples collected from Mochou Lake, Xuanwu Lake and Qinhuai River in Nanjing, analyzed the correlation between leaching contents of heavy metals and various forms and between content of organic matter and leachability of heavy metals and between organic matter and organic

Xu Ying; Lu Jing-ling

2010-01-01

213

Regression Analysis of Dissolved Heavy Metals in Storm Water Runoff from Elevated Roadways  

Microsoft Academic Search

This proposed research focused on the prediction and identification of dissolved heavy metals in storm water runoff from elevated roadways. Storm water runoff from highways transports a significant load of contaminants, especially heavy metals and particulate matter, to receiving waters. Heavy metals, either in dissolved or particulatebound phases, are unique in the fact that unlike organic compounds, they are not

Ruben Erlacher

2005-01-01

214

A Mechanism Study of Reflectance Spectroscopy for Investigating Heavy Metals in Soils  

Microsoft Academic Search

Conventional methods for investigating heavy metal contamination in soil are time consuming and expensive. In this study, we (i) explored refl ectance spectroscopy as an alternative method for assessing heavy metals, and (ii) further explored the physicochemical mechanism that allows estima- tion of heavy metals with the refl ectance spectroscopy method. We fi rst investigated the spectral response of changing

Yunzhao Wu; Jun Chen; Junfeng Ji; Peng Gong; Qilin Liao; Qingjiu Tian; Hongrui Ma

2007-01-01

215

Voltammetric analysis of the competition between calcium and heavy metals for complexation by humic material  

Microsoft Academic Search

The competition between calcium and the heavy metals zinc(II) and cadmium(II) in their interaction with humic substances has been studied by differential pulse anodic stripping voltammetry at constant ionic strength. Two experimental methodologies were employed: (1) addition of humic acid to a solution of heavy metal; and (2) addition of heavy metals to a humic acid solution, both using various

Marc A. G. T. van den Hoop; Herman P. van Leeuwen; JoséPaulo Pinheiro; Ana M. Mota; Maria de L. Simões Gonçalves

1995-01-01

216

Industrial hemp ( Cannabis sativa L.) growing on heavy metal contaminated soil: fibre quality and phytoremediation potential  

Microsoft Academic Search

Hemp (Cannabis sativa L.) was used to examine its capability as a renewable resource to decontaminate heavy metal polluted soils. The influence of heavy metals on the fibre quality was of special interest. Determination of heavy metal content was carried out by means of atomic absorption spectroscopy (AAS). Four different parts of the plant were examined: seeds, leaves, fibres and

P. Linger; J. Müssig; H. Fischer; J. Kobert

2002-01-01

217

Heavy Metal Removal by Novel CBD-EC20 Sorbents Immobilized on Cellulose  

Microsoft Academic Search

Heavy metals are major contributors to pollution of the biosphere, and their efficient removal from contaminated water is required. Biosorption is an emerging technology that has been shown to be effective in removing very low levels of heavy metal from wastewater. Although peptides such as metallothioneins or phytotchelatins are known to immobilize heavy metals, peptide-based biosorbents have not been extensively

Zhaohui Xu; Weon Bae; Ashok Mulchandani; Rajesh K. Mehra; Wilfred Chen

2002-01-01

218

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

E-print Network

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

Paris-Sud XI, Université de

219

Solid phase heavy metal separation using composite ion-exchange membranes  

Microsoft Academic Search

Selective removal of heavy metals from sludges or soil is a challenging problem because the heavy metals constitute a small fraction (usually <5%) of the solid phase, the rest being a background of innocuous non-toxic materials which are not important from a regulatory viewpoint. However, the non-toxic background materials may interact with the heavy metals through generation of high buffer

S. Sengupta; A. K. Sengupta

1996-01-01

220

INFLUENCE OF COMPOST FROM SEA WEEDS ON HEAVY METAL DYNAMICS IN THE SOIL-PLANT SYSTEM  

Microsoft Academic Search

SUMMARY Using compost in agriculture can cause environ- mental problems because it may contain toxic substances. Particular attention should be paid to the possible pres- ence of heavy metals in compost. However, in these cases the severity of pollution depends on the chemical form of the heavy metals. Studies on the environmental effects of heavy metal levels in compost show

Paola Castaldi; Giovanni Garau; Pietro Melis

221

Concentration and speciation of heavy metals during water hyacinth composting.  

PubMed

The Tessier sequential extraction method was employed to investigate the changes in heavy metals speciation (Zn, Cu, Mn, Fe, Pb, Ni, Cd and Cr) during water hyacinth (Eichhornia crassipes) composting. Results showed that, the contents of total metals concentration were increased during the composting process. The largest proportion of metals was found in the residual fraction which was in more stable form and is consequently considered unavailable for plant uptake. Reducible and oxidizable fractions of Ni, Pb and Cd were not found in all trials during water hyacinth composting. The concentrations of Cu and Cd were very low comparative to the other metals, but the percentage of exchangeable and carbonate fractions were similar as other metals. From this study it can be concluded that the appropriate proportion of cattle manure addition (Trial 4) significantly reduced the mobile and easily available fractions (exchangeable and carbonate fractions) during the composting process. PMID:22989643

Singh, Jiwan; Kalamdhad, Ajay S

2012-11-01

222

Bacterial sorption of heavy metals. [Bacillus cereus  

SciTech Connect

Four bacteria, Bacillus cereus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa, were examined for the ability to remove Ag{sup +}, Cd{sup 2+}, Cu{sup 2+}, and La{sup 3+} 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 Cd{sup 2+} and Cu{sup 2+}, 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 Cd{sup 2+} removal and B. subtilis removed the most Cu{sup 2+}. Removal of Ag{sup +} from solution by bacteria was very efficient; an average of 89% of the total Ag{sup +} was removed from the 1 mM solution, while only 12, 29, and 27% of the total Cd{sup 2+}, Cu{sup 2+}, and La{sup 3+}, respectively, were sorbed from 1 mM solutions. Electron microscopy indicated that La{sup 3+} 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 Cd{sup 2+} nor Cu{sup 2+} provided enough electron scattering to identify the location of sorption. The affinity series for bacterial removal of these metals decreased in the order Ag > La > Cu > Cd. The results indicate that bacterial cells are capable of binding large quantities of different metals.

Mullen, M.D.; Wolf, D.C. (Univ. of Arkansas, Fayetteville (USA)); Ferris, F.G.; Beveridge, T.J.; Flemming, C.A. (Univ. of Guelph, Ontario (Canada)); Bailey, G.W. (Environmental Protection Agency, Athens, GA (USA))

1989-12-01

223

Characterization of heavy metal particles embedded in tire dust.  

PubMed

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

Adachi, Kouji; Tainosho, Yoshiaki

2004-10-01

224

The role of metal corrosion in inflammatory processes: induction of adhesion molecules by heavy metal ions  

Microsoft Academic Search

Prosthetic devices undergo corrosion processes after implantation including the release of certain amounts of metal ions into the adjacent tissues. On reaching the bloodstream, a systemic influence of those ions may be envisaged. Cell adhesion molecules (CAMs) are recognized as an essential component of the mechanisms of endothelial damage. To study the influence of selected heavy metals on human umbilical

C. L. Klein; P. Nieder; M. Wagner; H. Köhler; F. Bittinger; C. J. Kirkpatrick; J. C. Lewis

1994-01-01

225

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

226

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

Microsoft Academic Search

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

Abdolkarim Chehregani; Fariba Mohsenzade; Froogh Vaezi

2009-01-01

227

Materials management in an internationally safeguarded fuels reprocessing plant. [1500 and 210 metric tons heavy metal per year  

SciTech Connect

The first volume of this report summarizes the results and conclusions for this study of conventional and advanced nuclear materials accounting systems applicable for both large (1500 MTHM/y) and small (210 MTHM/y) spent-fuel reprocessing facilities subject to international verification.

Hakkila, E.A.; Cobb, D.D.; Dayem, H.A.; Dietz, R.J.; Kern, E.A.; Markin, J.T.; Shipley, J.P.; Barnes, J.W.; Scheinman, L.

1980-04-01

228

Botanical plants could rid soil of heavy metals  

SciTech Connect

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

Brennan, M.

1993-04-20

229

Heavy metals in Ratnapura alluvial gem sediments, Sri Lanka  

NASA Astrophysics Data System (ADS)

The valuable gems in Sri Lanka are found from the sedimentary gem deposits in Ratnapura District, which are found as alluvial deposits some are about >50 m deep. Gem bearing gravel layer is taken out from the mine, washed by panning to recover the gem minerals in the heavy mineral fraction, is a common practice in the gem mining area. Gem bearing sediment layer is associated with different heavy minerals in which different trace metals as Co, Cr, Cu, Al, Zr, Pb and As also can be present. During panning, the sediment is washed away and the heavy metals attached to the sediments are released into the environment. Hence we studied the lability and bioavailability of arsenic and other heavy metals from the gem sediments. Sediment samples were collected from 15 small scale gem mines (3 soil layers- top, gem mineral layer and layer below gem bearing gravel layer), air dried and sieved to obtain <63?m fraction. Bioavailable, exchangeable and residual fractions were 0.01M CaCl2, 1M NaOAc, pH 8.2 and microwave digestion using HF, HNO3 and HClO4. Filtered samples were analyzed for As, Co, Zn, Mn, Cu, Ni, Pb and Fe using atomic absorption spectrophotometer (GBC 933AA). Total digestion results in different layers indicated that heavy metals show an increasing pattern with depth. About 4 gem bearing gravel layers were consist of high concentrations of Ni (>150 mg/kg), Cu (>150 mg/kg), Pb (>400 mg/kg), Zn (>600 mg/kg) and Co ions (>100 mg/kg). Arsenite in the gem sediments were low and recorded as <5mg/kg. Total arsenic analysis is under investigation. Highest concentrations for bioavailable and exchangeable (leach to water) metals were Fe>Co>Zn>Mn>Ni>Cu>Pb. Sediments from few gem pits showed considerably high concentrations of metals analyzed. In some places Fe, Ni, Cu, Zn reported high in bioavailable fractions 70, 25, 20, 10 mg/kg respectively. Mobilization of these metals may increase due to changes in the pH and the presence of other ions in the environment. High concentrations of toxic metals in exchangeable and bioavailable fractions indicate the risk on plant and animals as well as the open water bodies and groundwater sources.

Vithanage, M. S.; Hettiarachchi, J. K.; Rajapaksha, A. U.; Wijesekara, H.; Hewawasam, T.

2011-12-01

230

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

231

Extraction of heavy metals from soils using biodegradable chelating agents.  

PubMed

Metal pollution of soils is widespread across the globe, and the clean up of these soils is a difficulttask. One possible remediation technique is ex-situ soil washing using chelating agents. Ethylenediaminetetraacetic acid (EDTA) is a very effective chelating agent for this purpose but has the disadvantage that it is quite persistent in the environment due to its low biodegradability. The aim of our work was to investigate the biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS), iminodisuccinic acid (IDSA), methylglycine diacetic acid (MGDA), and nitrilotriacetic acid (NTA) as potential alternatives and compare them with EDTA for effectiveness. Kinetic experiments showed for all metals and soils that 24 h was the optimum extraction time. Longer times only gave minor additional benefits for heavy metal extraction but an unwanted increase in iron mobilization. For Cu at pH 7, the order of the extraction efficiency for equimolar ratios of chelating agent to metal was EDDS > NTA> IDSA > MGDA > EDTA and for Zn it was NTA > EDDS > EDTA >MGDA > IDSA. The comparatively low efficiency of EDTA resulted from competition between the heavy metals and co-extracted Ca. For Pb the order of extraction was EDTA > NTA >EDDS due to the much stronger complexation of Pb by EDTA compared to EDDS. At higher concentration of complexing agent, less difference between the agents was found and less pH dependence. There was an increase in heavy metal extraction with decreasing pH, but this was offset by an increase in Ca and Fe extraction. In sequential extractions EDDS extracted metals almost exclusively from the exchangeable, mobile, and Mn-oxide fractions. We conclude that the extraction with EDDS at pH 7 showed the best compromise between extraction efficiency for Cu, Zn, and Pb and loss of Ca and Fe from the soil. PMID:14968886

Tandy, Susan; Bossart, Karin; Mueller, Roland; Ritschel, Jens; Hauser, Lukas; Schulin, Rainer; Nowack, Bernd

2004-02-01

232

Evaluation of heavy metal contamination in Phaeozem of northeast China.  

PubMed

Surface and profile Phaeozem soil samples from 31 locations affected by various anthropogenic activities such as mining, chemical manufacturing, traffic emission and pesticide application were collected in Heilongjiang Province and Jilin Province, northeast China. The range of total concentrations of four heavy metals Cd, Pb, Cu and Zn in the soil was 0.011-3.137, 10.31-62.34, 9.74-51.21 and 39.54-247.59 mg kg(-1), respectively, determined using the acidic digestion procedure. Four methods including single contamination evaluation, background concentration comparison, surface/subsurface concentration comparison and exchangeable fraction evaluation were used to evaluate the extent of metal contamination in Phaeozem. The results indicated that different activities increased the concentrations of the heavy metals in surface soils, where high concentrations of cadmium and lead were found close to chemical plants and in the suburbs of the investigated cities. The four methods showed a general trend of increased soil contamination with heavy metals. Cadmium was of the most concern compared with the other contaminated elements in the study area, due to the long-term phosphatic fertilizer utilization and industrial activities. The proper evaluation method for cadmium contamination was the background concentration comparison, while for zinc and copper was the single contaminative index evaluation. Cadmium and lead could be the potential environmental risk in the Phaeozem area based on the different evaluations. PMID:16724244

Guo, G L; Zhou, Q X

2006-08-01

233

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

234

Competitive adsorption of dyes and heavy metals on zeolitic structures.  

PubMed

The adsorption of Acid blue 25, basic blue 9, basic violet 3, Pb(2+), Ni(2+), Zn(2+) and Cd(2+) ions has been studied in single and dye-metal binary solutions using two mineral materials: Clinoptilolite (CL) and ER (Erionite). These zeolites were characterized by FT-IR spectroscopy; potentiometric titration and nitrogen adsorption isotherms at 77 K to obtain their textural parameters. Results indicated that ER has an acidic character and a high specific surface (401 m(2) g(-1)) in contrast with the zeolite CL (21 m(2) g(-1)). Surprisingly, the removal of dyes was very similar for the two zeolites and they showed a considerable selectivity by the basic dyes in comparison with the acid dyes. In the case of heavy metals, ER was more effective in the adsorption process showing a selectivity of: Pb(2+) > Ni(2+) > Zn(2+) > Cd(2+). In the multicomponent adsorption experiments an antagonistic effect was observed in the removal of basic dyes and heavy metals. Particularly, the adsorbed amount of basic violet 3 decreased more significantly when the heavy metals are presents in contrast with the basic blue 9. PMID:23321372

Hernández-Montoya, V; Pérez-Cruz, M A; Mendoza-Castillo, D I; Moreno-Virgen, M R; Bonilla-Petriciolet, A

2013-02-15

235

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

Microsoft Academic Search

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

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

2009-01-01

236

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

237

Heavy metal interactions with phosphatic clay: sorption and desorption behavior.  

PubMed

Heavy metals produced and released during agricultural and industrial activities may pose a serious threat to the environment. This study investigated the effectiveness of phosphatic clay, a by-product of the phosphate mining industry, for immobilizing heavy metals (Pb(+2), Cd(+2), and Zn(+2)) from aqueous solutions. A batch equilibrium technique was adopted to evaluate metal sorption in the presence of 0.05 M KNO3 background electrolyte solution. The amounts of metals sorbed onto phosphatic clay decreased in the order Pb(+2) > Cd(+2) > Zn(+2). Desorption data suggest that a large fraction of metals sorbed onto phosphatic clay stayed intact under a wide variation in extracting solution pH (ranging from 3 to 10). Desorption rates were slowest for Pb followed by Cd and Zn. Only 8.1 to 23.1% of Pb, 8.4 to 45% of Cd, and 21.9 to 73.9% of Zn sorbed on phosphatic clay was mobilized by USEPA toxicity characteristic leaching procedure (TCLP) solutions at pH 2.93+/-0.05 and 4.93+/-0.05, respectively. Formation of fluoropyromorphite [Pb10(PO4)6(F2)], confirmed by scanning electron microscopy (SEM) and X-ray diffraction (XRD), after reaction of aqueous Pb with phosphatic clay suggested that precipitation remained the dominant mechanism for Pb removal from aqueous solution. In the case of aqueous Cd and Zn interaction with phosphatic clay, we are not able to confirm the formation of a new amorphous and/or crystalline phase on the basis of available information. Other possible sorption mechanisms for Cd and Zn may include sorption and coprecipitation. Thus, phosphatic clay may be an effective amendment for in situ immobilization of heavy metals in contaminated soils and sediments. PMID:11790002

Singh, S P; Ma, L Q; Harris, W G

2001-01-01

238

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

239

Heavy metal removel from minewaters by alkaline waste products  

NASA Astrophysics Data System (ADS)

One of the serious environmental problems of the Western Urals area (Russia) is the consequence of the cessation of mining in the Kizel Coal Basin. After mine closure, acid mine waters (pH about 3) with excessive heavy metal contents began to pollute ground surface and rivers. The methodology of neutralization of acid mine water and heavy metal removal by alkaline waste products is discussed in the paper. Waste products are non-toxic and consist of 70-80% of calcite. As a result of neutralization, the sediment becomes a mixture of iron and gypsum hydroxide and carbonate calcium with neutral pH. Mobile forms of Fe, Al, Mn, Pb and others were not revealed. The pilot field experiment showed the prospect and low cost of this technology.

Maximovich, N. G.; Khayrulina, E. A.

2009-04-01

240

Heavy metal poisoning: the effects of cadmium on the kidney  

Microsoft Academic Search

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

Nikhil JohriGregory Jacquillet; Grégory Jacquillet; Robert Unwin

2010-01-01

241

Sorption of heavy metals on blast furnace sludge  

Microsoft Academic Search

An investigation into the use of sludge, a by-product of the steel industry, as an adsorbent for the removal of heavy metals from liquid effluents was carried out. Gases produced in the blast furnace were washed and led towards a Dorr thickener where the sludge was obtained as a suspension. The sorption of Pb2+, Zn2+, Cd2+, Cu2+ and Cr3+ on

A. López-Delgado; C. Pérez; F. A. López

1998-01-01

242

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

243

Sorption of heavy metals onto hydrophobic parts of aquatic plants  

SciTech Connect

The ability of the roots of Eichhornia crassipes (water hyacinth), Tripha latifolia (common cattail) and Sparganium minimum (burr reed) to accumulate lead and mercury ions from aqueous solution was investigated. The relative abilities of the hydrophilic and hydrophobic portions of the root material to accumulate these ions was studied and it was found that the hydrophilic portion accumulates substantially more of the heavy metal ions than the hydrophobic portion. An attempt is made to explain this better sorption ability.

Smith, R.W.; Robichaud, K.; Misra, M. [Univ. of Nevada, Reno, NV (United States)

1995-12-31

244

The Distribution of Carcinogenic Heavy Metals in Cyprus Soil  

Microsoft Academic Search

\\u000a The number of cancer cases has been deliberately increasing both in Turkish and Greek Cypriot communities in Cyprus. The presence\\u000a of various carcinogens in the environment is suspected to be the major cause of this increase. The main aim of this study\\u000a was to identify the heavy metal contamination in Cyprus soil, mainly lead, cadmium and arsenic that are involved

M. Ertan Akun; Rezan Fahrio?lu Yamac?; Christophoros Charalambous; Savvas Lechtvich; Mustafa B. A. Djamgoz

245

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

246

Synthesis of heavy metal organometallic compounds: Final report  

SciTech Connect

Goal was the preparation of heavy metal organometallic compounds, especially gold compounds, which were reasonably stable and reasonably volatile at room temperature. Our approach to the problem via gold atom reactions at low temperatures led to the successful preparation of two new compounds: bis(trifluoromethyl)gold-..mu..-bromide dimer and bis(trifluoromethyl)gold-..mu..-iodide dimer. Efforts to prepare hexafluoroacetylacetonates, ethoxides, and PF/sub 3/ coordination compounds of gold were unsuccessful.

Bell, J.P.; Norem, N.T.; Margrave, J.L.

1987-07-15

247

Synthesis of heavy metal organometallic compounds: Final report  

Microsoft Academic Search

Goal was the preparation of heavy metal organometallic compounds, especially gold compounds, which were reasonably stable and reasonably volatile at room temperature. Our approach to the problem via gold atom reactions at low temperatures led to the successful preparation of two new compounds: bis(trifluoromethyl)gold-..mu..-bromide dimer and bis(trifluoromethyl)gold-..mu..-iodide dimer. Efforts to prepare hexafluoroacetylacetonates, ethoxides, and PFâ coordination compounds of gold were

J. P. Bell; N. T. Norem; J. L. Margrave

1987-01-01

248

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

249

Trace Elements and Heavy Metals Status in Arabian Camel  

Microsoft Academic Search

In the desert, camel rearing is an important cultural fact. In the present paper, 240 Arabian camels from Emirates were sampled\\u000a for the determination of trace elements and different heavy metals. The following elements were tested: copper, zinc, iron,\\u000a aluminium, arsenic, boron, barium, cobalt, chromium, cadmium, manganese, molybdenum, nickel, selenium, strontium and lead.\\u000a The variation factors included age, sex and

Bernard Faye; Rabiha Seboussi; Mostafa Askar

250

Chemical changes in heavy metals in the leachates from Technosols.  

PubMed

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

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

2009-09-01

251

Mutagenic activity of heavy metals in soils of wayside slopes  

Microsoft Academic Search

The genotoxic properties of soils polluted with heavy metals were studied on two wayside slopes covered with trees in the\\u000a city of Voronezh. The nucleolar test in cells of the apical meristem of Zebrina pendula Schnizl. roots was used. The genotoxic effect of the soils was revealed according to the increased number of 2-and 3-nucleolar\\u000a cells (from 41 to 54%

A. I. Fedorova; V. N. Kalaev; Yu. G. Prosvirina; S. A. Goryainova

2007-01-01

252

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

253

A simple and versatile PSA system for heavy metal determinations  

Microsoft Academic Search

An easy to build potentiometric stripping analysis system for heavy metal determinations (Zn, Cd, Pb, Cu) is described which\\u000a reaches good sensitivity and precision. Main components are an IBM compatible computer, an ADDA-conversion card and two selfmade\\u000a electrodes, so it can be realized for one tenth of the price of complete commercial systems. A graphite pencil lead covered\\u000a with a

A. Bund; J. Dittmann; D. Lordkipanidze; G. Schwitzgebel

1996-01-01

254

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

255

Removal of heavy metals from solution using biocompatible polymers  

Microsoft Academic Search

Well characterised, hydrophobic, poly(vinylidene fluoride) and poly(sulfone) membranes, a physisorbed amphiphillic surfactant as an affi nity linker with covalently attached bio-specific ligands to demonstrate heavy metal ion binding and re-use is reported. Central to this technology are the easy to manufacture membranes and a biocompatible Pluronic™ surfactant that serves multiple functions, where it acts not only as an affi nity

Selvan Govender; W. Przybylowicz; Pieter Swart

2009-01-01

256

Morphological changes in an acidophilic bacterium induced by heavy metals  

Microsoft Academic Search

The Acidiphilium strains inhabit acidic mine regions where they are subjected to occasional environmental stresses such as high and low temperatures,\\u000a exposure to various heavy metals, etc. Change in morphology is one of the strategies that bacteria adopt to cope with environmental\\u000a stresses; however, no study on this aspect has been reported in the case of Acidiphilium sp. This work

Rajdeep Chakravarty; Pataki C. Banerjee

2008-01-01

257

Plant cell responses to heavy metals: molecular and physiological aspects  

Microsoft Academic Search

The effect of lead, cadmium and cooper on protein pattern, free radicals and antioxidant enzymes in root of Lupinus luteus L. were investigated. Heavy metals inhibited growth of lupin roots, which was accompanied by increased synthesis and accumulation\\u000a of a 16 kDa polypeptide (Przymusi?ski et al. 1991 Biochem. Physiol. Pflanzen., 187:51–57). This component has been earlier identified as immunologically related

Edward A. Gwó?d?; Roman Przymusitiski; Renata Rucitiska; Joanna Deckert

1997-01-01

258

Heavy metal accumulation in soil after application of organic wastes  

Microsoft Academic Search

Municipal solid waste compost and cattle manure are used as organic fertilizers in agriculture and horticulture. These wastes,\\u000a however, may also have some negative effects on the agricultural environment. This study investigates the effects of municipal\\u000a solid waste compost of Kerman (MSC) and cattle manure (CM) on availability of the heavy metal in calcareous soil (extractable\\u000a with EDTA) in greenhouse

Majid Fekri; Soheila Kaveh

259

Heavy Metals and Pesticides Analysis from Black Sea Algae  

Microsoft Academic Search

Our studies were focused on heavy metals (Cd, Cu, Zn, and Pb) and pesticides analysis from two different types of marine algae\\u000a in order to assess their capabilities to be used as raw material for pharmaceutical purposes without risks for human health.\\u000a The analysed algae, Cystoseira barbata and Ceramium rubrum, have been collected from Romanian Black Sea Coast in the

Simona Lupsor; Gabriela Stanciu; Dan Epure; Elisabeta Chirila

260

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

261

Micellar enhanced ultrafiltration of heavy metals using lecithin  

E-print Network

and costly. Micellar Enhanced Ultrafiltration (MEUF), which combines the advantages of both reverse osmosis and ultrafiltration, has been shown effective in the treatment of aqueous wastes for heavy metals with the use of synthetic surfactants... such as sodium dodecyl sulfate (SDS). Lecithin, a natural surfactant, is inexpensive, non-toxic, and biodegradable. In this project the binding characteristics of lecithin to cadmium, copper, lead, nickel, and lead were examined. The process parameters of a...

Ahmadi, Saman Nameghi

2012-06-07

262

Characterization of heavy metal particles embedded in tire dust  

Microsoft Academic Search

Tire dust is a significant pollutant, especially as a source of zinc in the urban environment. This study characterizes the morphology and chemical composition of heavy metal particles embedded in tire dust and traffic-related materials (brake dust, yellow paint, and tire tread) as measured by a field emission scanning electron microscope equipped with an energy dispersive X-ray spectrometer (FESEM\\/EDX). In

Kouji Adachi; Yoshiaki Tainosho

2004-01-01

263

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

264

Scanning electron microscopic analysis of heavy metal resistant microorganisms  

Microsoft Academic Search

Industrial or mining activities can cause serious environmental problems by the contamination of large areas. In these polluted\\u000a habitats selection pressure have led to adaptation in microorganisms now containing special resistance mechanisms as a result\\u000a of the permanent exposure to exceedingly high concentrations of heavy metals. Recently van Nostrand et al. [1] isolated four\\u000a actinobacterial strains, among them two of

S. Nietzsche; A. Schmidt; E. Kothe; M. Westermann; W. Richter

265

Correlation analyses on binding behavior of heavy metals with sediment matrices  

Microsoft Academic Search

This article presents the amounts of heavy metals bound to the sediment matrices (carbonates, Fe-oxides, Mn-oxides, and organic matter), the correlations between any two heavy-metal binding fractions, and the correlations between sediment matrices and their heavy-metal binding fractions. Data consisted of 313 sets obtained from five main rivers (located in southern Taiwan) were analyzed by statistical methods. Among six heavy

Kuang-Chung Yu; Li-Jyur Tsai; Shih-Hsiung Chen; Shien-Tsong Ho

2001-01-01

266

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

267

Bioaccumulation of heavy metals by Phragmites australis cultivated in synthesized substrates  

Microsoft Academic Search

Accumulation of heavy metals from various oxides with adsorbed cadmium by wetland plant Phragmites australis was studied to evaluate the fate of heavy metals in the sediment of constructed wetlands. Hoagland solution was used as nutrition supply, and single metal oxide with adsorbed cadmium was applied as contaminant to study the accumulation characteristics of cadmium and the substrate metals by

He WANG; Yongfeng JIA

2009-01-01

268

Geochemical indices allow estimation of heavy metal background concentrations in soils  

Microsoft Academic Search

Defining background concentrations for heavy metals in soils is essential for recognizing and managing soil pollution. However, background concentrations of metals in soils can vary naturally by several orders of magnitude. Moreover, many soils have also been subject to unquantifiable anthropogenic inputs of metals, in some cases, for centuries. Hence determination of heavy metal background concentrations in soils has to

R. E. Hamon; M. J. McLaughlin; R. J. Gilkes; A. W. Rate; B. Zarcinas; A. Robertson; G. Cozens; N. Radford; L. Bettenay

2004-01-01

269

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

270

Heavy metal concentrations in Louisiana waterways, sediments, and biota  

SciTech Connect

In this investigation polarographic methods (along with GFAAS and ICP) have been used to study the distribution of lead and chromium in Bayou Trepagnier and Devil`s Swamp. Both laboratory and field research have been conducted. Separation and extraction methodology appropriate for analysis of the contaminants at these sites have been developed. Particular attention has been paid to extraction methods for chromium which do not lead to valence state conversion. The availability of such techniques is essential to take full advantage of polarography, a method capable of performing speciation analysis. The results indicate that there is a very inhomogeneous distribution of heavy metals in these environments. In Devil`s Swamp, for example, separation and analysis of aqueous and variously sized particulate moieties in the water and sediment compartments were conducted to determine the partition of lead between them. The results showed that the average lead content was 14.7 ppb and 19.8 ppm, respectively, in these compartments. Apparently bull frogs in Devil`s Swamp can bioaccumulate lead (compared to the measured water level), since the muscle concentration was found to be about 0.6 ppm. This phenomenon is being investigated in a Xenopus frog laboratory model of heavy metal uptake. The basic methodology validated in this study should be fairly generally applicable to assays of other heavy metals.

Bundy, K.J.; Berzins, D. [Tulane Univ., New Orleans, LA (United States). Biomedical Engineering Dept.

1994-12-31

271

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

272

Heavy metal contamination in the Taimyr Peninsula, Siberian Arctic.  

PubMed

The Taimyr Peninsula is directly north of the world's largest heavy metal smelting complex (Norilsk, Russia). Despite this proximity, there has been little research to examine the extent of contamination of the Taimyr Peninsula. We analyzed heavy metal concentrations in lichen (Cetraria cucullata), moss (Hylocomium splendens), soils, lake sediment, freshwater fish (Salvelinus alpinus, Lota lota and Coregonus spp.) and collared lemming (Dicrostonyx torquatus) from 13 sites between 30 and 300 km from Norilsk. Element concentrations were low in both C. cucullata and H. splendens, although concentrations of Al, Fe, Cu, Ni and Pb were significantly higher than those in Arctic Alaska, probably due to natural differences in the geochemical environments. Inorganic surface soils had significantly higher concentrations of Cd, Zn, Pb and Mg than inorganic soils at depth, although a lake sediment core from the eastern Taimyr Peninsula indicated no recent enrichment by atmospherically transported elements. Tissue concentrations of heavy metals in fish and lemming were not elevated relative to other Arctic sites. Our results show that the impact of the Norilsk smelting complex is primarily localized rather than regional, and does not extend northward beyond 100 km. PMID:12493191

Allen-Gil, S M; Ford, J; Lasorsa, B K; Monetti, M; Vlasova, T; Landers, D H

2003-01-01

273

Heavy Metal Contamination in the Taimyr Peninsula, Siberian Arctic  

SciTech Connect

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

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

2003-01-01

274

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

275

[Determination of trace elements and heavy metals in spaceflight achyranthes].  

PubMed

Concentration of trace elements and heavy metals is an important aspect to appraise the quality of Chinese traditional medicine. Seven kinds of trace elements and five kinds of heavy metals in spaceflight achyranthes were analyzed by the method of ICP-MS. The results showed that spaceflight achyranthes contained many wholesome elements, such as Ca, Fe, Zn, Mn, Cu, Se and Mo, whose concentrations are 9182.252 microg x g(-1) x DW, 310.5 microg x g(-1) x DW, 24.718 microg x g(-1) x DW, 18416.97 ng x g(-1) x DW, 5518.97 ng x g(-1) x DW, 1747.692 ng x g(-1) x DW and 211.87 ng x g(-1) x DW respectively. But the content of heavy metals is also high, as the concentrations of As, Pb, Hg, Cd and Cr are 514. 332 ng x g(-1) x DW, 1657.65 ng x g(-1) x DW, 13.212 ng x g(-1) x DW, 49.22 ng x g(-1) x DW and 922.038 ng x g(-1) x DW respectively, which accords with the relevant standard. PMID:18800734

Rui, Yu-kui; Li, Jin-gui

2008-06-01

276

Water Purification Using Functional Nanomaterials: Sequestering Toxic Heavy Metals  

SciTech Connect

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

Fryxell, Glen E.

2008-02-01

277

Understanding molecular mechanisms for improving phytoremediation of heavy metal-contaminated soils.  

PubMed

Heavy metal pollution of soil is a significant environmental problem with a negative potential impact on human health and agriculture. Rhizosphere, as an important interface of soil and plants, 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 or mycorrhizas have received more and more attention. In addition, some plants possess a range of potential mechanisms that may be involved in the detoxification of heavy metals, and they manage to survive under metal stresses. High tolerance to heavy metal toxicity could rely either on reduced uptake or increased plant internal sequestration, which is manifested by an interaction between a genotype and its environment.A coordinated network of molecular processes provides plants with multiple metal-detoxifying mechanisms and repair capabilities. The growing application of molecular genetic technologies has led to an increased understanding of mechanisms of heavy metal tolerance/accumulation in plants and, subsequently, many transgenic plants with increased heavy metal resistance, as well as increased uptake of heavy metals, have been developed for the purpose of phytoremediation. This article reviews advantages, possible mechanisms, current status and future direction of phytoremediation for heavy-metal-contaminated soils. PMID:19821782

Hong-Bo, Shao; Li-Ye, Chu; Cheng-Jiang, Ruan; Hua, Li; Dong-Gang, Guo; Wei-Xiang, Li

2010-03-01

278

Chitosan removes toxic heavy metal ions from cigarette mainstream smoke  

NASA Astrophysics Data System (ADS)

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

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

2013-09-01

279

Soil metatranscriptomics for mining eukaryotic heavy metal resistance genes.  

PubMed

Heavy metals are pollutants which affect all organisms. Since a small number of eukaryotes have been investigated with respect to metal resistance, we hypothesize that many genes that control this phenomenon remain to be identified. This was tested by screening soil eukaryotic metatranscriptomes which encompass RNA from organisms belonging to the main eukaryotic phyla. Soil-extracted polyadenylated mRNAs were converted into cDNAs and 35 of them were selected for their ability to rescue the metal (Cd or Zn) sensitive phenotype of yeast mutants. Few of the genes belonged to families known to confer metal resistance when overexpressed in yeast. Several of them were homologous to genes that had not been studied in the context of metal resistance. For instance, the BOLA ones, which conferred cross metal (Zn, Co, Cd, Mn) resistance may act by interfering with Fe homeostasis. Other genes, such as those encoding 110- to 130-amino-acid-long, cysteine-rich polypeptides, had no homologues in databases. This study confirms that functional metatranscriptomics represents a powerful approach to address basic biological processes in eukaryotes. The selected genes can be used to probe new pathways involved in metal homeostasis and to manipulate the resistance level of selected organisms. PMID:23663419

Lehembre, Frédéric; Doillon, Didier; David, Elise; Perrotto, Sandrine; Baude, Jessica; Foulon, Julie; Harfouche, Lamia; Vallon, Laurent; Poulain, Julie; Da Silva, Corinne; Wincker, Patrick; Oger-Desfeux, Christine; Richaud, Pierre; Colpaert, Jan V; Chalot, Michel; Fraissinet-Tachet, Laurence; Blaudez, Damien; Marmeisse, Roland

2013-10-01

280

Heavy metals and neurodegenerative diseases: an observational study.  

PubMed

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

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

2014-11-01

281

Study on impact of heavy metal accumulation in Brachythecium populeum (Hedw.) B.S.G  

Microsoft Academic Search

Mussoorie, Uttarakhand, western Himalaya, India is a popular tourist destination, selected for the comprehensive study on effects of heavy metals from vehicular exhaust which remain air borne for a long time, on the epiphytic moss Brachythecium populeum Hedw. (B.S.G.). Moss bags were transplanted in residential, heavy and low vehicular movement areas ascertain comparable levels of accumulation. The heavy metals Fe,

Shalini Sharma

2009-01-01

282

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

283

Heavy metal concentrations in edible barnacles exposed to natural contamination.  

PubMed

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

Dionísio, M; Costa, A; Rodrigues, A

2013-04-01

284

Amperometric biosensors for the determination of heavy metals  

NASA Astrophysics Data System (ADS)

A bioelectrochemical method for the determination of heavy metal ions has been developed. This method is based on the inhibition effect of metal ions on the enzymatic activity of oxidase enzymes. The enzymatic activity was determined with an amperometric hydrogen peroxide probe. The inhibition effect on enzymes in solution and covalently immobilized on polymeric supports has been evaluated. Hg(II) was the metal ion that inhibited almost all the enzymes, particularly glycerol-3-P oxidase. Hg(II) was detected in the 0.05/0.5 ppm range with the enzyme in solution. Calibration curves for Hg(II) were also obtained with the other oxidase enzymes in the 0.5/10 ppm range. The other metal ions tested inhibited the enzymes more specifically. The metal ion/enzyme systems which gave the best inhibition were Se(IV)/glutathione oxidase, Ni(II)/sarcosine oxidase, V(V)/glutathione oxidase, Cu(II)/alcohol oxidase from Pichia Pastoris and Cd(II)/D-aminoacid oxidase. All these metal ions were detected in the 0.1/10 ppm range using the enzymes in solution or covalently immobilized.

Compagnone, Dario; Palleschi, Giuseppe; Varallo, Giuseppe; Imperiali, PierLuigi

1995-10-01

285

Heavy metal removal from water/wastewater by nanosized metal oxides: a review.  

PubMed

Nanosized metal oxides (NMOs), including nanosized ferric oxides, manganese oxides, aluminum oxides, titanium oxides, magnesium oxides and cerium oxides, provide high surface area and specific affinity for heavy metal adsorption from aqueous systems. To date, it has become a hot topic to develop new technologies to synthesize NMOs, to evaluate their removal of heavy metals under varying experimental conditions, to reveal the underlying mechanism responsible for metal removal based on modern analytical techniques (XAS, ATR-FT-IR, NMR, etc.) or mathematical models, and to develop metal oxide-based materials of better applicability for practical use (such as granular oxides or composite materials). The present review mainly focuses on NMOs' preparation, their physicochemical properties, adsorption characteristics and mechanism, as well as their application in heavy metal removal. In addition, porous host supported NMOs are particularly concerned because of their great advantages for practical application as compared to the original NMOs. Also, some magnetic NMOs were included due to their unique separation performance. PMID:22018872

Hua, Ming; Zhang, Shujuan; Pan, Bingcai; Zhang, Weiming; Lv, Lu; Zhang, Quanxing

2012-04-15

286

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

287

Heavy metals in edible seaweeds commercialised for human consumption  

NASA Astrophysics Data System (ADS)

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

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

2009-01-01

288

Availability of applied heavy metals as a function of type of soil material and metal source  

SciTech Connect

The authors applied the heavy metals Cd, Cu, Ni, and Zn, as sulfate salts and as lime-stabilized, digested Washington, D.C., sewage sludge, to surface and subsurface horizon materials of six Maryland soils in the greenhouse. Rates of metal addition were equivalent to field rates of 224 metric tons (t)/ha of the sludge. Corn (Zea mays L.) was grown for 30 d, 13 mo after treatment application, and the tissue was analyzed for metals. Yields of plant material were generally enhanced by sludge and suppressed by metal salts. Tissue levels of both Cd and Zn were considerably elevated. In general the sludge did not elevate tissue Cu and Ni, whereas metal salts slightly elevated tissue Cu and Ni with some soil materials. An interaction between type of soil material and source of metal on plant tissue metal levels was observed. Essentially inert soil materials tended to produce tissue with the highest metal levels when metal-salt-treated, but with the lowest metal levels when sludged. Conversely, reactive soil materials, tended to produce tissue with relatively lower levels of metals than other materials when metal-salt-treated, but with relatively high levels when sludged.

Korcak, R.F.; Fanning, D.S.

1985-07-01

289

Adsorption of heavy metal ion from aqueous single metal solution by chemically modified sugarcane bagasse  

Microsoft Academic Search

This work describes the preparation of new chelating materials derived from sugarcane bagasse for adsorption of heavy metal ions in aqueous solution. The first part of this report deals with the chemical modification of sugarcane bagasse with succinic anhydride. The carboxylic acid functions introduced into the material were used to anchor polyamines, which resulted in two yet unpublished modified sugarcane

Osvaldo Karnitz; Leandro Vinicius Alves Gurgel; Júlio César Perin de Melo; Vagner Roberto Botaro; Tânia Márcia Sacramento Melo; Rossimiriam Pereira de Freitas Gil; Laurent Frédéric Gil

2007-01-01

290

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

Microsoft Academic Search

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

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

291

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

292

Heavy metal-activated synthesis of peptides in Chlamydomonas reinhardtii  

SciTech Connect

In this study, the authors have addressed the capacity of the green alga Chlamydomonas reinhardtii to produce metal-binding peptides in response to stress induced by the heavy metals Cd{sup 2+}, Hg{sup 2+}, and Ag{sup +}. Cells cultured in the presence of sublethal concentrations of Cd{sup 2+} synthesized and accumulated oligopeptides consisting solely of glutamic acid, cysteine, and glycine in an average ratio of 3:3:1. Cadmium-induced peptides were isolated in their native form as higher molecular weight peptide-metal complexes with an apparent molecular weight of approximately 6.5 {times} 10{sup 3}. The isolated complex bound cadmium (as evidenced by absorption spectroscopy) and sequestered (with a stoichiometry of 0.7 moles of cadmium per mole of cysteine) up to 70% of the total cadmium found in extracts of cadmium-treated cells. In Hg{sup 2+}-treated cells, the principal thiol-containing compound induced by Hg{sup 2+} ion was glutathione. It is possible that glutathione functions in plant cells (as it does in animal cells) to detoxify heavy metals. Cells treated with Ag{sup +} ions also synthesized a sulfur-containing component with a charge to mass ratio similar to Cd{sup 2+}-induced peptides. But, in contrast to the results obtained using Cd{sup 2+} as an inducer, these molecules did not accumulate to significant levels in Ag{sup +}-treated cells. The presence of physiological concentrations of Cu{sup 2+} in the growth medium blocked the synthesis of the Ag{sup +}-inducible component(s) and rendered cells resistant to the toxic effects of Ag{sup +}, suggesting competition between Cu{sup 2+} and Ag{sup +} ions, possibly at the level of metal uptake.

Howe, G.; Merchant, S. (Univ. of California, Los Angeles (United States))

1992-01-01

293

Aquatic macrophytes potential for the simultaneous removal of heavy metals (Buenos Aires, Argentina)  

Microsoft Academic Search

Heavy metal removal from water has been approached by using different technologies. Phytotechnologies, with an increasing development during the last two decades, involve using plants for metal removal. Three autochthonous floating macrophytes, common in pampean shallow lakes (Argentina), Pista stratiotes, Spirodela intermedia and Lemna minor were used in laboratory experiences for the simultaneously removal of several heavy metals (Fe, Cu,

Patricia Miretzky; Andrea Saralegui; Alicia Fernández Cirelli

2004-01-01

294

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

295

Heavy metal complexation with naturally occurring organic ligands in wetland ecosystems  

Microsoft Academic Search

The mode, rate, and extent of heavy metal uptake by freshwater wetlands were investigated as well as heavy metal complexation by a variety of soluble organics. One study involved adding Cd, Cu, Mn, and Zn to septage from Waldo, Florida, and pumping the wastewater through a 10 x 40-m corridor in a cypress swamp. Soluble concentrations of all four metals

Tuschall; J. R. Jr

1981-01-01

296

Chelator-induced bioextraction of heavy metals from artificially contaminated soil by mushroom (Coprinus comatus)  

Microsoft Academic Search

This study investigated the potential use of chelator-induced bioextraction of heavy metals from soil by Coprinus comatus in a pot experiment. Two production waves of the mushroom were obtained to determine biomass and metal concentration. The application of ethylenediaminetetraacetic acid (EDTA) or nitrilotriacetate (NTA) slightly inhibited the growth of C. comatus, but significantly enhanced the accumulation of heavy metals in

Feng Cen; Lan Chen; Yuanjia Hu; Heng Xu

2011-01-01

297

Chelator-induced bioextraction of heavy metals from artificially contaminated soil by mushroom (Coprinus comatus)  

Microsoft Academic Search

This study investigated the potential use of chelator-induced bioextraction of heavy metals from soil by Coprinus comatus in a pot experiment. Two production waves of the mushroom were obtained to determine biomass and metal concentration. The application of ethylenediaminetetraacetic acid (EDTA) or nitrilotriacetate (NTA) slightly inhibited the growth of C. comatus, but significantly enhanced the accumulation of heavy metals in

Feng Cen; Lan Chen; Yuanjia Hu; Heng Xu

2012-01-01

298

Use of Single Extraction Methods to Predict Bioavailability of Heavy Metals in Polluted Soils to Rice  

Microsoft Academic Search

Human exposure to toxic heavy metals via dietary intake is of increasing concern. Heavy-metal pollution of a rice production system can pose a threat to human health. Thus, it was necessary to develop a suitable extraction procedure that would represent the content of metal available to rice plants (Oryza sativa L.). The aim of this study was to predict, on

Ming-Kui Zhang; Zhao-Yun Liu; Huo Wang

2010-01-01

299

Analysis of Heavy metals in Water, Sediments and Fish samples of Madivala Lakes of Bangalore, Karnataka  

Microsoft Academic Search

? Abstract : Heavy metal (Pb, Cd, Cr, Ni ) concentration in water sediments and fish was analysed from Madivala lake in the month of June 2008. There was an appreciable increase in metal concentrations in going from the water to the sediment samples.The Heavy metal concentration, in water was in the order Pb > Cr > Cd > Ni

Abida Begum; HariKrishna S; Irfanulla Khan

300

Analysis of heavy metal sources in storm water from urban areas  

Microsoft Academic Search

The input of heavy metals into surface waters is a serious impairment of the aquatic environment. The emissions of heavy metals via point and diffuse pathways into the German river basins were thus quantified for the period of 1985 through 2005. The total emission into the German river systems decreased for each metal during the observed period. This reduction is

U. Scherer; S. Fuchs

2009-01-01

301

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 metals; Baltic Sea; EOF analysis 1. Introduction The Baltic Sea is one of the largest brackish water 2003; accepted 10 October 2003 Abstract Heavy metal concentrations from annual sampling in the period

Dippner, Joachim W.

302

HEAVY METALS CONCENTRATIONS IN THE LARGEST WATERSHED BASIN OF EAST URUMIEH LAKE, IRAN  

Microsoft Academic Search

Heavy metals concentration (Ni, Cr, Pb, Fe and Cu) was determined in water at five sampling sites in Talkheroud River. The measurements of the metal levels were carried out using atomic absorption spectroscopy. In order to interpret analytical results, several statistical methods were applied. There were statistically significant differences in the concentration of heavy metals among different months, while differences

N. Haji; A. R. Hasani; M. Farahnak Ghazani; N. Kasebi

303

Crustaceans as biological indicators of heavy metal pollution in Lake Balaton (Hungary)  

Microsoft Academic Search

Trace metals (Cd, Cu, Pb, Zn) were measured in mixed zooplankton samples collected from the open water of Lake Balaton (Hungary) in order to assess spatial and seasonal changes in the heavy metal load of different sites, during 1996–2000.Samplings were performed usually twice a year in different seasons (spring, summer and autumn). The heavy metal concentrations of zooplankton biomass were

Anna Farkas; János Salánki; István Varanka

2003-01-01

304

Effects of Temperature on the Sensitivity of Sludge Worm Tubifex tubifex Müller to Selected Heavy Metals  

Microsoft Academic Search

The present study evaluates the effect of temperature on the sensitivity of the freshwater tubificid sludge worm Tubifex tubifex Müller to 10 heavy metal ions. Metals used in this study were cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, and zinc. The acute toxicity of these heavy metals was studied at 15, 20, 25, and 30°C. The percentage mortality,

Rashmi Singh Rathore; B. S. Khangarot

2002-01-01

305

extended study of atmospheric heavy metal deposition in lithuania based on moss analysis  

Microsoft Academic Search

The use of different moss species – Hylocomium splendens,Pleurozium schreberi, Eurhynchium angustirete, Sphagnum and Rhytidiadelphus – was tested for the investigation of atmosphericheavy metal deposition. Maps representing heavy metal depositionpattern in Lithuania are presented for Cd, Cr, Cu, Fe, Ni, Pb and V.The most suitable species for heavy metal deposition studies was Hylocomium splendens in which the concentrations of metalswere

D. Ceburnis; Å. Rühling; K. Kvietkus

1997-01-01

306

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 Middlebury College, Middlebury, VT 05753 Abstract: Following earlier studies of metal retention in Great Sippewissett Marsh I have tested the long-term retention of heavy metals by the marsh. Beginning in the early

Vallino, Joseph J.

307

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

308

Mahayograj guggulu: Heavy metal estimation and safety studies  

PubMed Central

Objective: This study was conducted to estimate the heavy metal profile and determine the safety of Mahayograj guggulu, an Ayurvedic herbo-mineral preparation. Design: Mahayograj guggulu, manufactured by Shree Baidynath Ayurved Bhawan Pvt. Ltd., Gwalior Road, Jhansi - 284 003 (of batch number-07 and manufacturing date October 2004) was procured from the local market. Heavy metal concentrations were measured using an atomic absorption spectrophotometer. A total of 40 Charles Foster strain albino rats of either sex with an average body weight of 160–250 g were divided into four groups (Groups I, II, III and IV), with 10 animals in each group. Group I served as the control, while Group II, III and IV rats received Mahayograj guggulu at a dose of 54 (dose equivalent to human therapeutic dose), 270 (five-times the dose equivalent to the human therapeutic dose) and 540 (10-times the dose equivalent to human therapeutic dose) mg/kg, p.o. for 120 days. The effect of drug administration was noted on the ponderal, biochemical, hematological and histopathological parameters. In addition, urine examination was also carried out. At the end of the study, only six rats per group were sacrificed as per the IAEC advice. Results: Mahayograj guggulu was found to be safe at all dose levels tested. No significant behavioral changes were noted in any of the groups studied. The effect on food and water consumption and fecal and urine output remained unaffected in all groups during the study period. No major alterations were observed in hematology, serum biochemistry, necropsy and histopathology at the therapeutically advocated dose level. Heavy metal content measurement indicated levels of 25.8 µg/g for lead, 0.07 µg/g for mercury and 5.19 µg/g for arsenic. Conclusions: The test drug is well tolerated as no changes of a serious nature could be observed in any of the parameters assessed. PMID:21170206

Lavekar, G. S.; Ravishankar, B.; Gaidhani, S.; Shukla, V. J.; Ashok, B. K.; Padhi, M. M.

2010-01-01

309

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

310

The removal of heavy metal cations by natural zeolites.  

PubMed

In this study, the adsorption behavior of natural (clinoptilolite) zeolites with respect to Co(2+), Cu(2+), Zn(2+), and Mn(2+) has been studied in order to consider its application to purity metal finishing wastewaters. The batch method has been employed, using metal concentrations in solution ranging from 100 to 400 mg/l. The percentage adsorption and distribution coefficients (K(d)) were determined for the adsorption system as a function of sorbate concentration. In the ion exchange evaluation part of the study, it is determined that in every concentration range, adsorption ratios of clinoptilolite metal cations match to Langmuir, Freundlich, and Dubinin-Kaganer-Radushkevich (DKR) adsorption isotherm data, adding to that every cation exchange capacity metals has been calculated. It was found that the adsorption phenomena depend on charge density and hydrated ion diameter. According to the equilibrium studies, the selectivity sequence can be given as Co(2+) > Cu(2+) > Zn(2+) > Mn(2+). These results show that natural zeolites hold great potential to remove cationic heavy metal species from industrial wastewater. PMID:15533402

Erdem, E; Karapinar, N; Donat, R

2004-12-15

311

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

312

Impact of Heavy Metals on Water Loss from Lichen Thalli  

Microsoft Academic Search

Water loss in lichen speciesCladonia convoluta(Lam.) andC. rangiformis(L.) Hoffm. after exposure to heavy-metal (Pb, Cu, or Zn) solutions, either as single compounds or in combination, have been studied in this laboratory. Water loss was reduced in Pb-treatedC. convoluta,whereas inC. rangiformisit increased significantly with 10?2MPb treatment. Water loss increased significantly (P= 0.05) after Cu treatment inC. convolutabut was significantly reduced (P=

M. K. Chettri; T. Sawidis

1997-01-01

313

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

314

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

315

Assessment of heavy metals pollution in the upper Arkansas river of Colorado  

Microsoft Academic Search

Portions of the upper Arkansas River of Colorado are affected by heavy metal-laden inflows which are remnant of the mining era of the late 1800's. Based on studies of water quality, accumulation of heavy metals in river sediments, species diversity indices, fish populations, and concentration of heavy metals in aquatic organisms at 11 sampling stations in an 18-mile (28.968-km) reach,

J. F. LaBounty; J. J. Sartoris; L. D. Klein; E. F. Monk; H. A. Salman

1975-01-01

316

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

317

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

318

Regional distribution pattern of groundwater heavy metals resulting from agricultural activities  

Microsoft Academic Search

Contaminations of groundwater by heavy metals due to agricultural activities are growing recently. The objective of this study\\u000a was to evaluate and map regional patterns of heavy metals (Cd, Zn and Cu) in groundwater on a plain with high agricultural\\u000a activities. The study was conducted to investigate the concentration of heavy metals and distribution in groundwater in regions\\u000a of Shush

J. Nouri; A. H. Mahvi; G. R. Jahed; A. A. Babaei

2008-01-01

319

Assessment of heavy metals in sediments from a typical catchment of the Yangtze River, China  

Microsoft Academic Search

An intensive investigation was conducted to study the accumulation, speciation, and distribution of various heavy metals (As,\\u000a Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in sediments from the Yangtze River catchment of Wuhan, China. The potential ecological risks\\u000a posed by these heavy metals also were estimated. The median concentrations of most heavy metals (As, Cd, Cr, Cu, Ni, Pb,

Ying Wang; Zhifeng Yang; Zhenyao Shen; Zhenwu Tang; Junfeng Niu; Fan Gao

2011-01-01

320

Inhibitory effects of heavy metals on cytochrome P4501A induction in permanent fish hepatoma cells  

Microsoft Academic Search

The interactions in vitro of heavy metals Cd(II), Co(II), Cu(II), Ni(II), Pb(II), and Zn(II) with cytochrome P4501A (CYP1A) induction response and enzyme activity were studied in fish hepatoma cells PLHC-1. Cells were simultaneously exposed to heavy metals and to 3-methylcholanthrene (3-MC), an inducer of CYP1A. Heavy metals were added to the cells in different concentrations. Cytotoxicity were measured in the

B. J. Brüschweiler; F. E. Würgler; K. Fent

1996-01-01

321

Heavy metals: their pathway from the ground, groundwater and springs to Lake Góreckie (Poland)  

Microsoft Academic Search

The migration pathways of heavy metals derived from an area previously in agricultural use was investigated in the Wielkopolski\\u000a National Park (mid-western Poland). The heavy metals involved (Cd, Cu, Cr, Pb, Ni and Zn) were determined in groundwater,\\u000a the springs that feed Lake Góreckie and the lake itself. In order to show how the heavy metals may be set free

Barbara Walna; Marcin Siepak

322

Heavy Metal Toxicity and Differential Effects on the Hyperglycemic Stress Response in the Shrimp Palaemon elegans  

Microsoft Academic Search

Agricultural and industrial activities cause heavy metal pollution of the aquatic environment. The sensitivity of crustaceans\\u000a to heavy metals is well documented. However, the hormonal and metabolic target of physiological functions affected by sublethal\\u000a toxicity and stress responses have been scarcely investigated. Exposure of Palaemon elegans to increasing concentrations of heavy metals dissolved in artificial sea water resulted in an

S. Lorenzon; M. Francese; E. A. Ferrero

2000-01-01

323

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

Microsoft Academic Search

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

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

2009-01-01

324

Assessment of interference in biosorption of a heavy metal  

SciTech Connect

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

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

1997-05-20

325

Heavy metals contamination of soils surrounding waste deposits in Romania  

NASA Astrophysics Data System (ADS)

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

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

2003-05-01

326

Use of dried aquatic plant roots to adsorb heavy metals  

SciTech Connect

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

Robichaud, K.D.

1996-12-31

327

Natural and technogenic compounds of heavy metals in soils  

NASA Astrophysics Data System (ADS)

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

Vodyanitskii, Yu. N.

2014-04-01

328

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

PubMed

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

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

2013-07-01

329

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

PubMed

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

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

2014-08-01

330

Heavy metals processing near-net-forming summary progress report  

SciTech Connect

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

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

1994-09-01

331

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

332

[Migration characteristics of heavy metals during sintering of fly ash from municipal solid waste incinerator].  

PubMed

The sintering process is used to stabilize the heavy metal in fly ash from municipal solid waste incinerator (MSWI). Migration characteristics of 6 targeted heavy metals (Cd, Pb, Cu, Ni, Cr and Zn) in the sintering process of MSWI fly ash were investigated by experiments. Effect of several factors including sintering temperature, residence time, molding pressure and particle diameter on the migration of heavy metals were discussed in details. The results show that cadmium and lead are volatile metals, while nickel, copper, chromium and zinc belong to involatilizable metals. The effects of sintering temperature, residence time, molding pressure and particle diameter on the stabilizing efficiency differ from each other. The study shows that most of heavy metals are stabilized during the sintering process. The stabilizing efficiency of heavy metals was different for different elements. PMID:16447456

Li, Run-dong; Wang, Jian-ping; Wang, Lei; Li, Ai-min; Yang, Tian-hua; Wei, Li-hong; Nie, Yong-feng

2005-11-01

333

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

334

[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

335

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

336

Chemical methods and phytoremediation of soil contaminated with heavy metals.  

PubMed

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 plot experiment. Results showed that treatments with CC, SS and FS decreased Cd uptake by wetland rice, Chinese cabbage and wheat by 23-95% compared with the unamended control. Among the three amendments, FS was the most efficient at suppressing Cd uptake by the plants, probably due to its higher content of available silicon (Si). The concentrations of zinc (Zn), lead (Pb) and Cd in the shoots of vetiver grass were 42-67%, 500-1200% and 120-260% higher in contaminated plots than in control, respectively. Cadmium accumulation by vetiver shoots was 218 g Cd/ha at a soil Cd concentration of 0.33 mg Cd/kg. It is suggested that heavy metal-contaminated soil could be remediated with a combination of chemical treatments and plants. PMID:10819205

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

2000-07-01

337

Heavy metal concentrations in timberline trees of eastern Tibetan Plateau.  

PubMed

Concentrations of 14 heavy metals (Ag, As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Tl, V, and Zn) in needles, twigs, bark and xylem of spruce and fir collected at the timberline of eight sites along the Hengduan Mountains, eastern Tibetan Plateau, are reported. Twigs had the highest concentration for most of elements, while xylem had the lowest concentration. The connections between elements in twigs were much richer than other organ/tissues. Pb, Ni, As, Sb, Co, Cd, Hg, Cr and Tl which are partly through anthropogenic sources and brought in by monsoon, have been accumulated in twigs and needles by wet or dry deposition in south and east sites where are within or near pollutant sources. Under moderate pollution situation, vegetation are able to adjust the nutrient element (Cu and Zn) cycle rate, thus maintain a stable concentration level. Seldom V, Ag, and Mo are from external anthropogenic sources. Needles and twigs can be used as biomonitors for ecosystem environment when needles can simply distinguish the origin of elements and twigs are more sensitive to extra heavy metal input. PMID:24817526

Luo, Ji; She, Jia; Yang, Peijun; Sun, Shouqin; Li, Wei; Gong, Yiwen; Tang, Ronggui

2014-08-01

338

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

339

Topochemical Factors in Potentiation of Contraction by Heavy Metal Cations  

PubMed Central

In addition to the previously studied Zn2+, low concentrations (about 0.5 mM) of Be2+, Ba2+, Cd2+, Ni2+, Cu2+, Pt4+ and, outstandingly, 0.5 µM of UO22+, potentiate the twitch of frog sartorius and toe muscles by prolonging the active state of contraction. The degree of potentiation is a roughly S-shaped function of p(metal2+), suggesting that each metal binds to a ligand of the muscle fiber, representative apparent affinity constants being: UO22+, 5 x 106; Zn2+, 2.8 x 105; and Cd2+, 2 x 104. UO22+ potentiation effects are rapidly reversed by PO4, and Zn2+ and Cd2+ effects by EDTA, PO4, and cysteine. The rapidity of these reversals by the nonpenetrating EDTA and PO4, and the fact that heavy metal ions evidently potentiate by prolonging the action potential, indicate that the metal potentiators exert their primary action at readily accessible (i.e. plasma and T tubular) membrane sites. The relatively slow kinetics of development of potentiation, and the even slower reversal of it in pure Ringer's solution, indicate that the metal ions are bound to connective tissue, as well as to muscle fibers. The binding effects at the readily accessible membrane sites evidently impairs delayed rectification and thus modifies the action potential and excitation-contraction coupling so as to cause potentiation. SH is excluded, and PO4 and imidazole are possibilities, as the membrane ligand binding the potentiating metal ions. PMID:5961359

Sandow, Alexander; Isaacson, Allen

1966-01-01

340

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 ...

341

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 - ...

342

Bioaccumulation of heavy metals by Phragmites australis cultivated in synthesized substrates.  

PubMed

Accumulation of heavy metals from various oxides with adsorbed cadmium by wetland plant Phragmites australis was studied to evaluate the fate of heavy metals in the sediment of constructed wetlands. Hoagland solution was used as nutrition supply, and single metal oxide with adsorbed cadmium was applied as contaminant to study the accumulation characteristics of cadmium and the substrate metals by P. australis. After 45-d treatment, the bioaccumulation degree in root followed the order: Al(OH)3 > Al2O3 > Fe3O4 > MnO2 > FeOOH. Heavy metals absorbed by P. australis were largely immobilized by the roots with little translocation to aboveground parts. PMID:19999996

Wang, He; Jia, Yongfeng

2009-01-01

343

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

344

Pollution Status of Pakistan: A Retrospective Review on Heavy Metal Contamination of Water, Soil, and Vegetables  

PubMed Central

Trace heavy metals, such as arsenic, cadmium, lead, chromium, nickel, and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. In addition to these metals, copper, manganese, iron, and zinc are also important trace micronutrients. The presence of trace heavy metals in the atmosphere, soil, and water can cause serious problems to all organisms, and the ubiquitous bioavailability of these heavy metal can result in bioaccumulation in the food chain which especially can be highly dangerous to human health. This study reviews the heavy metal contamination in several areas of Pakistan over the past few years, particularly to assess the heavy metal contamination in water (ground water, surface water, and waste water), soil, sediments, particulate matter, and vegetables. The listed contaminations affect the drinking water quality, ecological environment, and food chain. Moreover, the toxicity induced by contaminated water, soil, and vegetables poses serious threat to human health.

Arshad, Jahanzaib; Iqbal, Farhat; Sajjad, Ashif; Mehmood, Zahid

2014-01-01

345

Heavy metals in locus ceruleus and motor neurons in motor neuron disease  

PubMed Central

Background The causes of sporadic amyotrophic lateral sclerosis (SALS) and other types of motor neuron disease (MND) remain largely unknown. Heavy metals have long been implicated in MND, and it has recently been shown that inorganic mercury selectively enters human locus ceruleus (LC) and motor neurons. We therefore used silver nitrate autometallography (AMG) to look for AMG-stainable heavy metals (inorganic mercury and bismuth) in LC and motor neurons of 24 patients with MND (18 with SALS and 6 with familial MND) and in the LC of 24 controls. Results Heavy metals in neurons were found in significantly more MND patients than in controls when comparing: (1) the presence of any versus no heavy metal-containing LC neurons (MND 88%, controls 42%), (2) the median percentage of heavy metal-containing LC neurons (MND 9.5%, control 0.0%), and (3) numbers of individuals with heavy metal-containing LC neurons in the upper half of the percentage range (MND 75%, controls 25%). In MND patients, 67% of remaining spinal motor neurons contained heavy metals; smaller percentages were found in hypoglossal, nucleus ambiguus and oculomotor neurons, but none in cortical motor neurons. The majority of MND patients had heavy metals in both LC and spinal motor neurons. No glia or other neurons, including neuromelanin-containing neurons of the substantia nigra, contained stainable heavy metals. Conclusions Uptake of heavy metals by LC and lower motor neurons appears to be fairly common in humans, though heavy metal staining in the LC, most likely due to inorganic mercury, was seen significantly more often in MND patients than in controls. The LC innervates many cell types that are affected in MND, and it is possible that MND is triggered by toxicant-induced interactions between LC and motor neurons. PMID:24330485

2013-01-01

346

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

347

Relationships between heavy metals and iron oxides, fulvic acids, particle size fractions in urban roadside soils  

NASA Astrophysics Data System (ADS)

Urban roadside soils are the “recipients” of large amounts of heavy metals from a variety of sources including vehicle emissions, coal burning waste and other activities. The behavior of heavy metals in urban roadside soils depends on the occurrence as well as the total amount. Accordingly, knowledge of the interactions between heavy metals and other constituents in the soil is required to judge their environmental impact. In this study, correlations of heavy metal concentrations (Pb, Zn, Cu, Ag, Se, Ni, Cr and Ba) to iron extracted using dithionite-citrate-bicarbonate (DCB) buffer (FeDCB), fulvic acids and particle size fractions were examined from the Xuzhou urban roadside soils. Heavy metals except for Cr and fulvic acids had a positive significant correlation with FeDCB, indicating these metals and fulvic acids are principally associated with the surfaces of iron oxides of the soils. Significant positive correlations were also found between the contents of fulvic acids and heavy metals, showing these heavy metals (especially for Cu, Ni and Cr) form stable complexes with fulvic acids. Such finding is of importance with regard to the increased mobilization of heavy metals, e.g., into freshwater ecosystems. Ag, Se and Cr are independent of particle size fractions because of their low concentrations of Ag and Se in the studied soils. Pb, Zn, Cu, Ba and Ag are mainly enriched in the finer soil particles (especially <16 ?m).

Wang, Xue-Song; Qin, Yong

2007-03-01

348

Studies on Microbial Heavy Metal Retention from Uranium Mine Drainage Water with Special Emphasis on Rare Earth Elements  

Microsoft Academic Search

Microbial heavy metal retention was studied using seepage water sampled from a former uranium mining site in Eastern Thuringia, Germany. The seepage water has a low pH and contains high concentrations of metals, including uranium, rare earth elements (REE), and other heavy metals. Microbial influence on sorption and\\/or active uptake of heavy metals was studied using REE patterns. Incubation of

D. Merten; E. Kothe; G. Büchel

2004-01-01

349

Surface binding of toxins and heavy metals by probiotics.  

PubMed

Removal of toxic metals and toxins using microbial biomass has been introduced as an inexpensive, new promising method on top of conventional methods for decontamination of food, raw material and concentrated. In this article the potential application of lactic acid bacteria and yeasts as the most familiar probiotics to eliminate, inactivate or reduce bioavailability of contamination in foods and feed has been reviewed. After fast glance to beneficial health effects and preservative properties of lactic acid bacteria, the mechanisms which explain antibacterial and antifungal efficiency as well as their antifungal metabolites are mentioned. Then the article has been focused on potential application of single strain or combination of lactic acid bacteria for removal of heavy metals (copper, lead, cadmium, chromium, arsenic), cyanotoxins (microcystin-LR, -RR, -LF) and mycotoxins (aflatoxin B1, B2, B2a, M1, M2, G1, G2, patulin, ochratoxin A, deoxynivalenol, fumonisin B1 and B2, 3-acetyldeoxynivalenol, deoxynivalenol, fusarenon, nivalenol, diacetoxyscirpenol, HT-2 and T-2 toxin, zearalenone and its derivative, etc) from aqueous solutions in vitro. Wherever possible the mechanism of decontamination and the factors influencing yield of removal are discussed. Some factors which can facilitate metal removal capacity of lactic acid bacteria including the strains, surface charge, pH, temperature, presence of other cations are introduced. The cell wall structure of lactic acid bacteria and yeasts are also introduced for further explanation of mechanism of action in complex binding of probiotic to contaminants and strength of mycotoxin- bacterium interaction. PMID:24329992

Zoghi, Alaleh; Khosravi-Darani, Kianoush; Sohrabvandi, Sara

2014-01-01

350

[Heavy metal]-Chlorophylls Formed in Vivo During Heavy Metal Stress and Degradation Products Formed During Digestion, Extraction and Storage of Plant Material  

Microsoft Academic Search

This chapter discusses the occurrence, properties and relevance of chlorophyll (Chl) degradation products that are formed\\u000a either in vivo in heavy metal-stressed plants or by digestion of algae in marine invertebrates, or that are formed during extraction or processing of dead plant material. The in vivo substitution of the central Mg2+ ion of chlorophyll by heavy metals constitutes an important

Hendrik Küpper; Frithjof C. Küpper; Martin Spiller

351

Distribution and contamination of heavy metals in surface sediments of the South Yellow Sea.  

PubMed

The distributions, annual sedimentation and atmospheric deposition flux of heavy metals have been studied in sediments of the South Yellow Sea (SYS), in order to evaluate their levels and pollution status. The higher concentrations of heavy metals were generally found in the central part of the SYS, which may be associated with the organic matters due to their high affinity to the metals. According to the calculated enrichment factor (EF) of the studied metals, Cd in the sediments posed a high risk to local environments, while Mn, Hg, Pb and Zn were at moderate risk levels. Sedimentation fluxes study in the SYS showed that most heavy metals were deposited in the Chinese offshore. Annual dry deposition flux of these metals indicated that the particulate heavy metals deposition via atmosphere also play an important role in biogeochemical cycles in the SYS. PMID:22906733

Yuan, Huamao; Song, Jinming; Li, Xuegang; Li, Ning; Duan, Liqin

2012-10-01

352

Algae utilization in assessment of the large Turawa Lake (Poland) pollution with heavy metals  

Microsoft Academic Search

This investigation was undertaken to determine the applicability of algae for the assessment of contamination level of water reservoirs with heavy metals. The alga Spirogyra sp. collected in the littoral zone of the Large Turawa Lake (artificial lake in Southern Poland) was used for the study. The concentrations of heavy metals accumulated in the alga inhabiting a flow-through water basin

Ma?gorzata Rajfur; Andrzej K?os; Maria Wac?awek

2011-01-01

353

Heavy metals in surface lake sediments on the Kola Penninsula as an index of air quality  

SciTech Connect

The investigations of heavy metal (Ni, Cu, Co, Zn, Pb, Cd, Hg) distribution in sediments of more than 100 lakes were carried out between 1989 and 1994. The study lakes are situated at different distances from two main heavy metal pollution sources of the Kola Peninsula-smelters of the Pechenganickel and Severonickel Companies. To assess the pollution extent of investigated lakes, values of factor and degree of contamination were calculated according to the method suggested by Hakanson (1980). Heavy metal contamination factor (C{sub f}) for each heavy metal was calculated as the quotient of concentration from the uppermost (0-1 cm) sediment to the mean preindustrial background value (concentrations from 20-30 cm sediment layers) for the investigated region. Degree of contamination (C{sub d}) was defined as the sum of all contamination factors for studied heavy metals. To quantitatively express the potential ecological risk of given contaminants created for ecosystems, risk factor (Er) for each heavy metal has been calculated. Er takes into account the toxicity of a heavy metal and bioproduction index (BPI) of a lake. Risk index (RI) was determined as the sum of all ecological risk factor for studied heavy metals.

Dauvalter, V. [Institute of the North Industrial Ecology Problems, Murmansk (Russian Federation)

1996-12-31

354

Heavy metal adsorption properties of a submerged aquatic plant ( Ceratophyllum demersum)  

Microsoft Academic Search

Heavy metals can be adsorbed by living or non-living biomass. Submerged aquatic plants can be used for the removal of heavy metals. In this paper, lead, zinc, and copper adsorption properties of Ceratophyllum demersum (Coontail or hornwort) were investigated and results were compared with other aquatic submerged plants. Data obtained from the initial adsorption studies indicated that C. demersum was

O. Keskinkan; M. Z. L. Goksu; M. Basibuyuk; C. F. Forster

2004-01-01

355

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

356

[Leaching and stabilization of heavy metal in the fly ash of medical wastes].  

PubMed

Through the experiments of leaching and melting on the fly ash of medical wastes, the influence of leaching time, L/S, pH and grain size on the leaching characteristics of heavy metal and the effect of melting on the stabilization of fly ash are studied. Results show that, following the leaching time extending, the leaching concentrations of heavy metals and lixiviate toxicity of heavy metals increase in the fly ash. When the ratio of liquid and solid add, the leaching concentrations of heavy metals obviously become big, and the Cd's leaching concentration is the biggest, when the ratio of liquid and solid is 90, the Cd' s leaching ratio exceed the percent of 70. At the time pH is about 7, the leaching concentrations of heavy metals are the lowest. When the grain size is the bigger or little, the leaching concentrations of heavy metals are lower, however when the grain size is 250-900 microm, the concentrations are higher. After fly ash melt in the high temperature, the lixiviate toxicity of heavy metals greatly reduce, which explains that the effect of melting on heavy metals' stabilization is very good. PMID:18637373

Tan, Zhong-xin; Liao, Hua-yong; Xie, Jian-jun; Wang, Xiao-bo; Li, Hai-bing; Zhao, Zeng-li

2008-04-01

357

Influence of vegetative filter strips on heavy metal retention in runoff waters: a laboratory evaluation  

Microsoft Academic Search

Point-polluted industrial sites can be exposed to water erosion, leading to a dispersion of, e.g., heavy metal contaminated soil particles. Sowing vegetative buffer strips could limit this problem. We therefore investigated the influence of different vegetative filter strips on heavy metal retention, for runoff water loaded with two different polluted sediments. An experimental flume was built in order to simulate

Thomas Lambrechts; Charlotte de Braekeleer; Anne Iserentant; Guido Rentmeesters; Stanley Lutts; Charles Bielders

2010-01-01

358

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

359

Towards a safe standard for heavy metals in reclaimed water used for fish aquaculture  

Microsoft Academic Search

The objective of the present study is to provide a basis for the development of a standard on the concentration of heavy metals in reclaimed water used for edible fish aquaculture, focusing on the four heavy metals addressed by the Israel standard for food quality (arsenic, cadmium, lead and mercury). A series of experiments were carried out on three commercial

M. Feldlite; M. Juanicó; I. Karplus; A. Milstein

2008-01-01

360

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

361

Heavy metals as markers for assessing environmental pollution from chemical warehouse and plastics fires  

Microsoft Academic Search

Case histories of large, accidental fires are presented to illustrate that heavy metals may be used as markers to assess the extent of localized environmental contamination resulting from fires. Due to the complexity of fire chemistry with respect to organic pollutants, determination of organic pollutants in the environment following a fire would be time consuming and expensive. Using heavy metals

Andrew A. Meharg; Michael C. French

1995-01-01

362

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

363

Heavy Metal Contamination from Electronic Waste Recycling at Guiyu, Southeastern China  

Microsoft Academic Search

Th is study evaluated the eff ect of electronic waste (e-waste) recycling activities at a regional center, Guiyu, Guangdong, China on heavy metal pollution in the surrounding waterway system. Surface water and sediment collected from the Lianjiang River and its tributaries were analyzed for concentrations of Cu, Pb, Ni, Cd, Hg, and As. Spatially, heavy metals in water and sediment

Yan Guo; Changjiang Huang; Hong Zhang; Qiaoxiang Dong

2009-01-01

364

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

365

Heavy metal bioaccumulation and effects on waterhyacinth weevils, Neochetina eichhorniae , feeding on waterhyacinth, Eichhornia crassipes  

Microsoft Academic Search

Both aquatic and terrestrial habitats frequently are subject to contamination by toxic heavy metals, yet very little is known about the influence of heavy metals absorbed by plant tissues upon the phytophagous insect fauna feeding upon these plants. As early as 1936 Hurd-Karrer and Poos (1936) reported that selenium was toxic to aphids. Byers and Zeiders (1976) indicated that the

Stratford H. Kay; William T. Haller

1986-01-01

366

Volatilization of the heavy metals during circulating fluidized bed combustion of forest residue  

Microsoft Academic Search

Increasing interest in using biomass for energy production has created a need to establish a method for its sustainable utilization. During combustion, the inorganic incombustible species in the biomass are converted into ash. The environmental impact on the heavy metals contained in the combustion product ash depends on the speciation of the heavy metals and the size distributions of the

Terttaliisa Lind; E. I. Kauppinen; T. Valmari; George Sfiris; Kristina Nilsson; Willy Maenhaut

1999-01-01

367

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

368

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

E-print Network

technological developments or scientific advances. They can also be further enabled by changes in regulatory, is advancing quickly, and is already being applied to radionuclides and heavy metals. Examples of other newvii Executive Summary The remediation of radionuclides and heavy metals using current technology

369

Heavy Metal Pollution by Atmospheric Transport in Natural Soils from the Northern Part of Eastern Carpathians  

Microsoft Academic Search

The present paper is a study of the heavy metal contamination ofnatural soils due to atmospheric transport in the northern partof Eastern Carpathians. The study area is located north of BaiaMare, the main Romanian centre for processing complex sulphideores. Ten undisturbed soil profiles of andosols and andic soilswere investigated. The distribution of heavy metals (Pb, Cu, Zn,Mn, Ni, Co, Cr

Carmen Donisa; Raluca Mocanu; Eiliv Steinnes; Alexandra Vasu

2000-01-01

370

The concept of controlled afforestation of dredged sediment landfills polluted with heavy metals  

Microsoft Academic Search

Landfilling of polluted dredged sediment from inland rivers is a current practice in Belgium. The soil matrix of landfilled dredged sediment is very rich in organic matter, clay and calcium carbonate, which means that leaching of heavy metals is of no environmental concern. Because of the strong adsorbing matrix, chemical extraction of heavy metals is very difficult. Tree growth is

VANDECASTEELE Bart; VOS Bruno

371

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

372

Heavy Metal Concentrations in Soils and Irrigation Waters in Thessaly Region, Central Greece  

Microsoft Academic Search

The purpose of this work was to provide information on heavy metals concentrations in soils and in irrigation water in Thessaly, Central Greece, where tobacco (Nicotiana tabacum) is cultivated. Tobacco tends to accumulate high levels of heavy metals, especially Cadmium. During the years 1998, 1999, and 2000, 795 surface soil samples (0 to 30 cm depth) and 200 water samples were

I. K. Mitsios; E. E. Golia; C. D. Tsadilas

2005-01-01

373

Extraction of Arsenic and Heavy Metals from Contaminated Mine Tailings by Soil Washing  

Microsoft Academic Search

In this study, the soil washing technique has been used to treat mine tailings contaminated heavily with arsenic and heavy metals at Jingok mine, which is one of the abandoned mines in Korea. The results showed that phosphoric acid, citric acid, oxalic acid, and sodium metabisulfite were highly effective in extracting arsenic and heavy metals. Among them, oxalic acid was

Myoung-Jin Kim; Taesuk Kim

2011-01-01

374

Content and Binding Forms of Heavy Metals, Aluminium and Phosphorus in Bog Iron Ores from Poland  

Microsoft Academic Search

Bog iron ores are widespread in Polish wetland soils used as meadows or pastures. Th ey are suspected to contain high concentrations of heavy metals, which are precipitated together with Fe along a redox gradient. Th erefore, soils with bog iron ore might be important sources for a heavy metal transfer from meadow plants into the food chain. However, this

Danuta Kaczorek; Gerhard W. Brümmer; Michael Sommer

2009-01-01

375

Heavy metal contamination of soil and vegetables in suburban areas of Varanasi, India  

Microsoft Academic Search

Heavy metal contamination of soil resulting from wastewater irrigation is a cause of serious concern due to the potential health impacts of consuming contaminated produce. In this study an assessment is made of the impact of wastewater irrigation on heavy metal contamination of Beta vulgaris (palak); this is a highly nutritious leafy vegetable that is widely cultivated and consumed in

Rajesh Kumar Sharma; Madhoolika Agrawal; Fiona Marshall

2007-01-01

376

Removal of Heavy Metals from COD Analysis Wastewater With an Organic Precipitant  

Microsoft Academic Search

Conventional treatment of wastewater samples generated from Chemical Oxygen Demand (COD) analysis in environmental laboratories usually encounters difficulty due to its strong acidity and high concentrations of heavy metals. This research explores an alternative method using an organic precipitant, dithiocarbamates, to remove heavy metals in wastewaters generated from COD analysis. The optimum treatment conditions were determined using four synthetic wastewaters.

Orathai Chavalparit; Maneerat Ongwandee; Patcharaporn Thaweesuwanporn

2008-01-01

377

Assessment of heavy metal pollution in surficial soils surrounding Zinc Industrial Complex in Zanjan-Iran  

Microsoft Academic Search

In this study the Zinc Industrial Complex located near the city of Zanjan-Iran was selected for detailed study. The objective of the study was to assess the extent and severity of heavy metal contamination of topsoils in this area. We examined the present degree and spatial distribution of heavy metal concentrations in 15 topsoil samples in the Zinc Industrial Complex

Abdolhossein Parizanganeh; Pooya Hajisoltani; Abbasali Zamani

2010-01-01

378

Spatial Patterns of Soil Heavy Metals in Urban-Rural Transition Zone of Beijing1  

Microsoft Academic Search

To identify the main sources responsible for soil heavy metal contamination, 70 topsoils were sampled from the Daxing County in the urban-rural transition zone of Beijing. The concentrations of heavy metals Cu, Zn, Pb, Cr, Cd, Ni, As, Se, Hg, and Co; the soil texture; and the organic matter content were determined for each soil sample. Descriptive statistics and geostatistics

HU Ke-Lid; F ZHANG; H LI; F HUANG; B LI

2006-01-01

379

Heavy metal content of rainwater in Geneva, New York during late 1982  

Microsoft Academic Search

Two topics of concern in atmospheric pollution are the acidity of rain and the possibility of heavy metal contamination. Acidity is caused by the reactions of oxides of nitrogen ~d of sulfur with water, leading to the ions H +, ~0^-, and SO 4 in rain (COWLING 1982). Heavy metal contamination ma~ come from dust, ocean spray, combustion and industrial

Carl F. Aten; John B. Bourke; John C. Walton

1983-01-01

380

Acute toxicity of four heavy metals to Benthic fish food organisms from the River Khan, Ujjain  

Microsoft Academic Search

The acute toxicity of four heavy metals (Hg, Zn, Cd and Pb) to two benthic invertebrates viz. Tubifex tubifex and 4th instar larvae of chironomous sp. from the River Khan (Ujjain) have been determined by static bioassay experiments. Although both Tubifex tubifex and chironomous larvae have been found to be resistant to heavy metals (Hg, Zn, Cd and Pb), the

S. A. Qureshi; A. B. Saksena; V. P. Singh

1980-01-01

381

Plant–microbe symbiosis for bioremediation of heavy metal contaminated soil: perspectives for Belarus  

Microsoft Academic Search

Problems of heavy metal and radionuclide contamination are very important for Belarus. About 23% of its territory is contaminated with radio- nuclides, some areas are heavily contaminated with Cu, Zn, Pb, and Cd. Heavy metals can be carcinogenic and mutagenic even at low doses, are not bio- degradable and are easily accumulated by live organisms. Phytoremediation and bioremediation technologies are

Alena Lopareva; Nadezhda Goncharova

382

Heavy Metal Concentrations in Nestlings of Black-Crowned Night Herons (Nycticorax nycticorax) in Zhengzhou, China  

Microsoft Academic Search

To assess the heavy metal accumulation level, distribution among tissues or organs, and gender related variations, concentrations of five heavy metal elements were examined in six tissues or organs of 10 nestlings of Black-crowned Night Herons (Nycticorax nycticorax) collected from urban district of Zhengzhou, China. Hg was found in all six tissues or organs and As in the muscle, heart,

Hongpeng Han; Hui Wu; Yanju Wu; Jing Zhang; Wenlin Wang

2011-01-01

383

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...

384

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...

385

ENGINEERING ASSESSMENT OF HOT-ACID TREATMENT OF MUNICIPAL SLUDGE FOR HEAVY METALS REMOVAL  

EPA Science Inventory

The hot-acid method for treating sludge was developed by the Walden Division of Abcor, Inc., to remove heavy metals from municipal wastewater sludge. Investigations by Walden have demonstrated the degrees to which heavy metals are solubilized. Sulfuric acid dosage at about 20 to ...

386

Response of microbial characteristics to heavy metal pollution of mining soils in central Tibet, China  

Microsoft Academic Search

Soil microbial activity plays a crucial role in soil microbiological processes, which can be used as a useful indicator to determine the ecological effects of heavy metal pollution on soils. The objective was to determine the effects of heavy metal pollution on mining soils at the Lawu mine of central Tibet, China on soil enzyme activities (sucrase, urease and acid

Fu-Ping Zhang; Cheng-Fang Li; Le-Ga Tong; Li-Xin Yue; Ping Li; Yang-Jin Ciren; Cou-Gui Cao

2010-01-01

387

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

Microsoft Academic Search

An electrochemical method is described for separating heavy metal values from a radioactive molten salt including Li halide at temperatures of about 500 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

1995-01-01

388

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

389

Bioleaching of heavy metals from sewage sludge using Acidithiobacillus thiooxidans  

NASA Astrophysics Data System (ADS)

Acidithiobacillus thiooxidans was isolated from sewage sludge using the incubation in the Waksman liquor medium and the inoculation in Waksman solid plate. It was found that the optimum conditions of the bioleaching included solid concentration 2%, sulfur concentration 5 g?L-1 and cell concentration 10%. The removal efficiency of Cr, Cu, Pb and Zh in sewage sludge, which was obtained from waste treatment plant, Jinshan, Fuzhou, was 43.65%, 96.24%, 41.61% and 96.50% in the period of 4˜10 days under the optimum conditions, respectively. After processing using the proposed techniques, the heavy metals in sewage sludge did meet the requirement the standards of nation.

Wen, Ye-Ming; Lin, Hong-Yan; Wang, Qing-Ping; Chen, Zu-Liang

2010-11-01

390

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

391

Toxicity of heavy metals (Zn, Cu, Cd, Pb) to vascular plants  

Microsoft Academic Search

The literature on heavy metal toxicity to vascular plants is reviewed. Special attention is given to forest plant species, especially trees, and effects at low metal concentrations, including growth, physiological, biochemical and cytological responses. Interactions between the metals in toxicity are considered and the role of mycorrhizal infection as well. Of the metals reviewed, Zn is the least toxic. Generally

Anna-Maj Balsberg Påhlsson; J. Vallgatan

1989-01-01

392

Parameters for Removal of Toxic Heavy Metals by Water Milfoil ( Myriophyllum spicatum )  

Microsoft Academic Search

Due to the increasing awareness of toxic heavy metals contamination to the environment, studies of metal accumulation from the view point of metal removal from contaminated water have been performed. Conventional methods including precipitation, oxidation, reduction, ion exchange, filtration, electrochemical treatment, membrane technologies and evaporation recovery are expensive or ineffective, especially when the metal concentrations are very low in the

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

1996-01-01

393

Initial results of QCM using for heavy metals determination in water  

Microsoft Academic Search

The electric current can deposit heavy metal ions on the surface of quartz crystal microbalance (QCM) electrode as it is connected to the minus of electric source. The kind of metal deposition from water solution depends on electrode voltage correctly to electrochemical series of metals. The gradual increase of voltage results in progressive deposition of next metal correctly to electrochemical

K. Weiss; W. Steplewski; J. Dojlido; B. Obminska; B. Dulmet

2003-01-01

394

Sorption of heavy metal metatartrate complexes on polystyrene anion exchangers.  

PubMed

The performance of polystyrene anion exchangers in purifying wastewaters containing metatartaric acid and heavy metal ions (especially those from electroless plating processes) was investigated. The following anion exchangers were selected: Lewatit MonoPlus M 500, Lewatit MonoPlus MP 64, Lewatit MP 62 and Amberlite IRA 402. A batch method was used to study the influence of: phase contact time (1-120 min); solution pH (2-9); concentration of initial heavy metal Cu(II), Zn(II), Co(II) and Ni(II) complexes (1.25 x 10(-4) M to 8.0 x 10(-3) M); temperature (303-333K); and interfering ions (Cl-, NO3-, SO4(2-), Ca2+, Mg2+). The amounts of Cu(II), Zn(II), Co(II) and Ni(II) complexes with metatartaric acid sorbed at equilibrium using the strongly basic anion exchanger Lewatit MonoPlus M 500 were equal to 7.25 mg/g, 3.21 mg/g, 3.78 mg/g and 3.98 mg/g, respectively. The equilibrium sorption capacity increased slightly with increasing temperature. The optimal pH sorption was found to be 6.5. The experimental data were analysed using the Langmuir and Freundlich models. The maximum adsorption capacities q(0) determined from the Langmuir adsorption equation equal to 7.53 mg/g, 3.75 mg/g, 3.55 mg/g and 4.60 mg/g were in good agreement with the experimental values for Lewatit MonoPlus M 500. The kinetic data obtained at different concentrations were modelled using pseudo first order, pseudo second order and intraparticle diffusion equations. The experimental data were well described by the pseudo second order kinetic model. PMID:21877538

Hubicki, Zbigniew; Geca, Marzena; Ko?ody?ska, Dorota

2011-04-01

395

Determination of heavy metal contents in some freshwater fishes.  

PubMed

The concentrations of heavy metals in tench, pike-perch, and common carp fish caught in four different seasons from Damsa dam lake (Nev?ehir) were determined. Heavy metal contents of fishes changed depending on seasons. The highest Al (20.894 mg/kg) in tench was established in winter, and the lowest Al (1.605 mg/kg) was determined in summer. Fe content of tench fish changed between 112.906 mg/kg (autumn) and 31.207 mg/kg (spring). In addition, Zn contents of tench were found between 36.0323 mg/kg (summer) and 430.586 mg/kg (winter). The results indicate that concentrations of Cu of tench varied from 0.1934 mg/kg (winter) to 15.422 mg/kg (autumn). Results indicate that concentrations varied from 2.923 mg/kg (autumn) to 32.078 mg/kg (summer) with a mean of 11.1893 mg/kg for Al; 0.2483 mg/kg (spring) to 3.3088 mg/kg (autumn) with a mean of 1.6189 mg/kg for Ni; 0.5325 mg/kg (spring) to 0.845 mg/kg (autumn) with a mean of 0.7234 for Pb; and 7.0464 mg/kg (winter) to 253.686 mg/kg (summer) with a mean of 133.6348 for Zn. In common carp, Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Se, Ga, and Te contents were determined as 3.9623 mg/kg; 0.1293, 0.2336, 0.0526, 0.1543, 4.2406, 0.726, 1.797, 0.6216, 6.8536, 0.1783, 0.7876, and 0.371 mg/kg in autumn, respectively. PMID:25119695

Mert, Ramazan; Ala?, Ali; Bulut, Sait; Ozcan, Mehmet Musa

2014-11-01

396

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

397

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

Microsoft Academic Search

An electrochemical method of separating heavy metal values from a radioactive molten salt including Li halide at temperatures of about 500°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

1993-01-01

398

Bioaccumulation of heavy metals by submerged macrophytes: looking for hyperaccumulators in eutrophic lakes.  

PubMed

To directly select submerged macrophytes with high accumulation capability from the field, 24 eutrophic lakes along the middle and lower reaches of the Yangtze River were investigated in the study. These eutrophic lakes have large amounts of heavy metals in both water and sediments because of human activities. The results showed that Najas marina is a hyperaccumulator of As and Cd, Ceratophyllum demersum is a hyperaccumulator of Co, Cr, and Fe, and Vallisneria natans is a hyperaccumulator of Pb. Strong positive correlations were found between concentrations of heavy metals in tissues of submerged macrophytes, probably because of coaccumulation of heavy metals. However, for most heavy metals, no significant correlations were found between submerged macrophytes and their surrounding environments. In conclusion, N. marina, C. demersum, and V. natans are good candidate species for removing heavy metals from eutrophic lakes. PMID:23582178

Xing, Wei; Wu, Haoping; Hao, Beibei; Huang, Wenmin; Liu, Guihua

2013-05-01

399

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

400

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

401

Application of ionic liquids for the removal of heavy metals from wastewater and activated sludge.  

PubMed

This paper presents the results of adsorption studies on the removal of heavy metals (Cr, Cu, Cd, Ni, Pb and Zn) from standard solutions, real wastewater samples and activated sewage sludge using a new technique of liquid-liquid extraction using quaternary ammonium and phosphonium ionic liquids (ILs). Batch sorption experiments were conducted using the ILs [PR4][TS], [PR4][MTBA], [A336][TS] and [A336][MTBA]. Removal of these heavy metals from standard solutions were not effective, however removal of heavy metals from the industrial effluents/wastewater treatment plants were satisfactory, indicating that the removal depends mainly on the composition of the wastewater and cannot be predicted with standard solutions. Removal of heavy metals from activated sludge proved to be more successful than conventional methods such as incineration, acid extraction, thermal treatment, etc. For the heavy metals Cu, Ni and Zn, ?90% removal was achieved. PMID:22546790

Fuerhacker, Maria; Haile, Tadele Measho; Kogelnig, Daniel; Stojanovic, Anja; Keppler, Bernhard

2012-01-01

402

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

PubMed

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 hazardous heavy metal-polluted soils by natural zeolite, with special emphasis on single/co-remediation. Based on the comments on hazardous heavy metal behavior characteristics in leaching and rhizosphere and remediation with zeolite for heavy metal-polluted soils, it indicated that the research of rhizosphere should be strengthened. Theory of remediation with natural zeolite could make breakthroughs due to the investigation on synthetic zeolite. Co-remediation with natural zeolite may be applied and studied with more prospect and sustainable recycling. PMID:19464110

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

2009-10-15

403

Heavy metals in the terrestrial isopod Porcellio scaber Latreille. II. Subcellular fractionation of metal-accumulating lysosomes from hepatopancreas  

Microsoft Academic Search

Two populations of metal contaminated Porcellio scaber Latreille were studied: one consisting of animals that had been fed heavy metals in the laboratory for several months, and one from a metal-polluted site in the field (Braubach, FRG). Density gradient centrifugation was performed on hepatopancreas homogenates in order to identify cellular fractions and their association with lead, copper and cadmium. Marker

Reinhard Dallinger; Fritz Prosi

1988-01-01

404

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

405

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

406

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

407

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

408

Interaction of Soil Heavy Metal Pollution with Industrialisation and the Landscape Pattern in Taiyuan City, China  

PubMed Central

Many studies indicated that industrialization and urbanization caused serious soil heavy metal pollution from industrialized age. However, fewer previous studies have conducted a combined analysis of the landscape pattern, urbanization, industrialization, and heavy metal pollution. This paper was aimed at exploring the relationships of heavy metals in the soil (Pb, Cu, Ni, As, Cd, Cr, Hg, and Zn) with landscape pattern, industrialisation, urbanisation in Taiyuan city using multivariate analysis. The multivariate analysis included correlation analysis, analysis of variance (ANOVA), independent-sample T test, and principal component analysis (PCA). Geographic information system (GIS) was also applied to determine the spatial distribution of the heavy metals. The spatial distribution maps showed that the heavy metal pollution of the soil was more serious in the centre of the study area. The results of the multivariate analysis indicated that the correlations among heavy metals were significant, and industrialisation could significantly affect the concentrations of some heavy metals. Landscape diversity showed a significant negative correlation with the heavy metal concentrations. The PCA showed that a two-factor model for heavy metal pollution, industrialisation, and the landscape pattern could effectively demonstrate the relationships between these variables. The model explained 86.71% of the total variance of the data. Moreover, the first factor was mainly loaded with the comprehensive pollution index (P), and the second factor was primarily loaded with landscape diversity and dominance (H and D). An ordination of 80 samples could show the pollution pattern of all the samples. The results revealed that local industrialisation caused heavy metal pollution of the soil, but such pollution could respond negatively to the landscape pattern. The results of the study could provide a basis for agricultural, suburban, and urban planning. PMID:25251460

Liu, Yong; Su, Chao; Zhang, Hong; Li, Xiaoting; Pei, Jingfei

2014-01-01

409

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

410

[Study on canopy spectral characteristics of paddy polluted by heavy metals].  

PubMed

Because of frequent mining, heavy metals are brought into environment like soils, water and atmosphere, resulting heavy metal contamination in the agricultural region beside mines. Heavy metals contamination causes vegetation stress like destruction of chloroplast structure, chlorophyll content decrease, blunt photosynthesis, etc. Spectral responses to changes in chlorophyll content and photosynthesis make it possible that remote sensing is applied in monitoring heavy metals stress on paddy plants. Field spectroradiometer was used to acquire canopy reflectance spectra of paddy plants contaminated by heavy metals released from local mining. The present study was conducted to (1) investigate discrimination of canopy reflectance spectra of heavy metal polluted and normal paddy plants; (2) extract spectral characteristics of contaminated paddy plants and compare them. By means of correlation analysis, sensitive bands (SB) were firstly picked out from canopy spectra. Secondly, on the basis of these sensitive bands, normalized difference vegetation indices (NDVI) were established, and then red edge position (REP) was extracted from canopy spectra via curve fitting of inverted Gaussian model. As a result of correlation analysis, 460, 560, 660 and 1 100 nm were considered respectively as sensitive band for Pb, Zn, Cu and As concentration in paddy leaves. Furthermore, heavy metal concentrations (Pb, Zn, Cu and As) were significantly correlated with NDVIs (Pb, NDV(510, 810); Zn, NDVI(510, 870; Cu, NDVI(660, 870); As, NDVI(510, 810)). Heavy metals were also significantly correlated with REP, however, the inflexion termed as spectral critical value (SCV) between low and high heavy metals concentrations should be considered during applying REP in remote sensing monitoring. Moreover, NDVI and REP are much better than SB in terms of capability of expressing spectral information. Therefore, heavy metals contamination in paddy plants can be remotely monitored via ground spectroradiometer when NDVI and REP are selected as spectral characteristics. PMID:20384139

Ren, Hong-Yan; Zhuang, Da-Fang; Pan, Jian-Jun; Shi, Xue-Zheng; Shi, Run-He; Wang, Hong-Jie

2010-02-01

411

Assessment of heavy metals contamination in roadside topsoil along Qinghai-Tibetan highway, China  

NASA Astrophysics Data System (ADS)

With the rapid development of road construction and increase of vehicles on the Qinghai-Tibetan Plateau over last few decades, traffic source heavy metals have been continuously emitted into roadside soils and caused a growing concern on potential pollution of soils. In this study, a soil survey was conducted along the Qinghai-Tibet highway (Xining-Maduo-Budongquan-Naqu-Lhasa), China, to investigate the status and influence factors of heavy metals (Cu, Cd, Pb and Zn) in roadside topsoil. A total of 32 sampling sites, 144 topsoil (0~2 cm) samples were collected at different distances to the highway edge (0 m, 10 m, 30 m, 50 m and 100m). Vehicle volume, soil types and road types have significantly impacts on concentrations of the four heavy metals. On the whole, heavy metal concentrations were higher in Budongquan-Naqu-Lhasa (BNL) segment with higher traffic volume than Xining-Maduo-Budongquan (XMB) segment with lower traffic volume. The heavy metals concentrations also show higher levels for asphalt roads than gravel roads, and a sequence of severely degraded meadow soil (MS) > slightly degraded MS > desert soil > non-degraded MS. Besides, concentrations of all the four heavy metals show exponentially decreasing relationships with roadside distances. Compared to the background values of heavy metals in the soils of Qinghai-Tibet Plateau, traffic source heavy metals pollution only exists within 10 m to the road edge in most segments. However, the maximum polluted distance can reach 30 m along the TMP segment. It should be noted that heavy metals pollution was more harmful to this high-altitude segment with fragile ecology. Keywords: Heavy Metal (Cu, Cd, Pb, Zn); Roadside soil; Qinghai-Tibet highway; Qinghai-Tibetan Plateau.

Zeng, C.; Zhang, F.; Yan, X.; Gao, D.

2012-12-01

412

Regional ecotoxicological hazards associated with anthropogenic enrichment of heavy metals.  

PubMed

Regional geochemical data of heavy metals are commonly used for environmental risk assessment and management. Often these data are based on so-called total concentrations, whereas the exposure to the mobile or reactive fraction of these elements finally determines whether the exposed ecosystem is at risk and to which extent. The objective of our research was to develop a wider applicable method for quantitative hazard assessment of soil metal contamination attributable to the activity of man, based on and illustrated with data from the Netherlands. Since chemical availability (0.43 M HNO3 extractable concentrations) of Cd, Cu, Pb and Zn appeared strongly related to the estimated anthropogenic enrichment, we used these concentrations to assess the hazard of human-induced enrichment of these metals. We expressed the enrichment hazard using the toxic pressure concept, which estimates the fraction of biological species (varying between 0 and 1) potentially affected due to the level of exposure to single metals or their local mixtures. This is done using logistic (enrichment) concentration/response models parameterized with ecotoxicological effect data from toxicity tests and mixture models. Hazards varied from very low toxic pressures (lower than 0.01) to (most often) toxic pressure less than 0.05, whereby the latter relates to the so-called 95%-protection criterion used in some soil protection legislations. In rare cases, the toxic pressure exceeded the value of 0.05, to an upper limit of 0.054 for Cd. The rank order of metal enrichment hazards suggests that Cd enrichment induces the largest hazard increase. There are limited (rank order) differences in enrichment hazards between soil types. Comparing the judgement of soils based on soil screening levels and based on toxic pressure of anthropogenic Cd, Cu, Pb and Zn enrichments, the soil screening values appear to more conservative. This exemplifies the use of soil screening values as a method to note regulatory concern, but not always indicating an actual hazard or risk. When screening values are exceeded, refined hazard insights can be obtained, as illustrated in this paper. This provides a more refined insight in the ecotoxic implications of human-induced metal enrichments in soils, as refined basis for risk management decisions. PMID:21424771

Spijker, J; Mol, G; Posthuma, L

2011-08-01

413

Speciation of heavy metals in biosolids of wastewater treatment plants at Mysore, Karnataka, India.  

PubMed

Urban wastewater treatment leads to the generation of large quantities of biosolids. Accumulation of biosolids is a problem of environmental relevance due to the existence of heavy metals in the biosolids. Determination of total metal in biosolid provides information relating pollution levels. Determination of their mobilization capacity and behaviour in the environment is an important task. An experimental approach commonly used for studying the mobility, transport and bioavailability of metal in biosolids is the use of selective sequential extraction procedure. In the present study an attempt has been made to study the heavy metal properties in biosolid samples collected from urban wastewater treatment plants located at Mysore, Karnataka. Few heavy metals selected for the present study are cadmium, chromium, copper, iron, nickel and zinc. The concentration of these metals in biosolids and their partition in different fractions are studied. The speciation of metals based on the sequential extraction scheme was carried out. The concentration of heavy metals is lower than that established by European legislation. The residual fraction has the maximum percentage of heavy metals whereas, only a small fraction of heavy metals (Fe, Zn and Cd) are extracted in the most soluble fractions, exchangeable and carbonate fractions. PMID:21424912

Bai, Shakunthala; Srikantaswamy, Shivanna; Krishnanandan, Vivek; Naik, Onkara P

2012-01-01

414

Removal Of Heavy Metals From Electroplating Wastewater By Anaerobic Bacteria  

NASA Astrophysics Data System (ADS)

Biosorption of heavy metals from simulated wastewater and the raw electroplating wastewater with ``BM (Biosorption of Metals) bacteria'' were investigated in this study. The influence of initial pH, biosorbents dose, concentration of ions, contact time and temperature on biosorption capacity of Cr(VI) and Ni(II) were studied. The optimum pH for biosorption of Cr(VI) was found to be low, and the removal efficiency of Cr(VI) was 98.60% with ``BM bacteria'' at pH 2. The removal efficiency of Ni(II) was increased with increasing the pH, and was enhanced up to 115% compared with the wastewater without BM bacteria. In this experiment, the ``BM bacteria'' efficiently removed Cu(II), Ni(II), Cr(VI), Zn(II) and COD from the raw electroplating wastewater, and the removal efficiencies were 98.92%, 99.92%, 99.86%, 99.93% and 45.20% respectively.

Ma, Wanggang; Sun, Peide; Song, Yingqi; Zhang, Yi; Yin, Jun

2010-11-01

415

Reduction of Heavy Metals by Cytochrome c(3)  

SciTech Connect

We report on reduction and precipitation of Se(VI), Pb(II), CU(II), U(VI), Mo(VI), and Cr(VI) in water by cytochrome c{sub 3} isolated from Desulfomicrobium baczdatum [strain 9974]. The tetraheme protein cytochrome c{sub 3} was reduced by sodium dithionite. Redox reactions were monitored by UV-visible spectroscopy of cytochrome c{sub 3}. Analytical electron microscopy work showed that Se(VI), Pb(II), and CU(II) were reduced to the metallic state, U(W) and Mo(W) to U(IV) and Mo(IV), respectively, and Cr(VI) probably to Cr(III). U(IV) and Mo(W) precipitated as oxides and Cr(III) as an amorphous hydroxide. Cytochrome c{sub 3} was used repeatedly in the same solution without loosing its effectiveness. The results suggest usage of cytochrome c{sub 3} to develop innovative and environmentally benign methods to remove heavy metals from waste- and groundwater.

ABDELOUAS,A.; GONG,W.L.; LUTZE,W.; NUTTALL,E.H.; SPRAGUE,F.; SHELNUTT,JOHN A.; STRIETELMEIER,B.A.; FRANCO,R.; MOURA,I.; MOURA,J.J.G.

2000-01-18

416

Mixed heavy metals tolerance and radial oxygen loss in mangrove seedlings.  

PubMed

The effects of a mixture of heavy metals (Pb, Zn and Cu) on growth, radial oxygen loss (ROL) and the spatial pattern of ROL were investigated in mangrove seedlings of three species: Aegiceras corniculatum, Avicennia marina and Bruguiera gymnorrhiza. Heavy metals inhibited the growth of seedlings and led to decreased ROL and changes in the "tight" barrier spatial pattern of ROL. There was a significant positive correlation between the amount of ROL from the roots of seedlings and metal tolerance. The species with the highest ROL amount, B. gymnorrhiza, were also the most tolerant to heavy metals. The "tight" barrier spatial ROL pattern was also related to metal tolerance in the seedlings. Therefore, we conclude that both ROL amount and "tight" barrier spatial ROL pattern in the roots of the mangrove seedlings play an important role in resistance to heavy metal toxicity. PMID:19692098

Liu, Y; Tam, N F Y; Yang, J X; Pi, N; Wong, M H; Ye, Z H

2009-12-01

417

The sorption of heavy-metal cations from EDTA complexes on acrylamide resins having oligo(ethyleneamine) moieties  

Microsoft Academic Search

Removal of heavy metals from solutions containing a powerful chelator EDTA and the separation of heavy metals from this anionic ligand are important for the efficient treatment of waste water and for recovery and reuse of heavy metals.The optimum working conditions of acrylamide sorbents having oligo(ethyleneamine) moieties for uptake of chelated heavy metals (i.e. molar ratio {EDTA: Me}solution sorption kinetics

Z. Matejka; Z. Zitkova

1997-01-01

418

Heavy metal bioaccumulation in Great Basin submersed aquatic macrophytes  

SciTech Connect

Seasonal element cycling and nutritional quality were determined in sago pondweed plant tissue. Leaf protein was 27% in July and 15% in December. Sago drupelet protein content was 9% in July and 6.5% in October. Sago plant tissue mineral, trace metal and non-structural carbohydrate content were high in the Fall. Submersed aquatic plant species from the Provo River drainage, Bear River MBR and Utah Lake - Provo Bay were significantly higher in heavy metals than aquatic species from remote wetlands. Extreme sodium concentrations were found in water, sediment and plant tissue in Ibis and Harrison pools (Fish Springs NWR). Boron, arsenic and selenium concentrations in plant tissue were much lower than those at Kesterson Reservoir, California. Submersed aquatic plants may act as channels that expedite the trophic movement of metal ions. The chemical structure of accumulated manganese and iron in sago pondweed plant tissue differed with time of year. June plant tissue manganese was fully hydrated. Accumulated manganese in October plant tissue was a Mn(II)Mn(III) mineral oxide. Accumulated iron was Fe(III) in both leaf and root tissue. Methylmercury was toxic to Lesser duckweed at very low doses (>0.1 [mu]g ml[sup [minus]1]). Increased pH improved frond survival in organic and inorganic mercury solutions. Duckweed should be considered as a sensitive phytoassay of methylmercury toxicity. Soil manganese and lead concentrations are correlated with distance from the roadway and traffic volume. Soil lead concentrations have moved deeper into the profile. Roadside aquatic plants were higher in manganese than herbaceous plants and grasses. Roadside snow and water were low in manganese and lead. Roadside soil and plants were apparently contaminated by Mn oxides from motor vehicle exhaust.

Lytle, C.M.

1994-01-01

419

Concentrations of some heavy metals in commercially important finfish and shellfish of the River Ganga  

Microsoft Academic Search

Heavy metals are dangerous to aquatic organisms and it can be bioaccumulated in the food chain leading to diseases in human.\\u000a Cumulative effects of metals or chronic poisoning may occur as a result of long-term exposure even to low concentrations.\\u000a The accumulation of heavy metals varies depending upon the species, environmental conditions, and inhibitory processes. Concentrations\\u000a of zinc, copper, lead,

Abhijit Mitra; Ranju Chowdhury; Kakoli Banerjee

420

Phytochelatins: The Principal Heavy-Metal Complexing Peptides of Higher Plants  

Microsoft Academic Search

A set of novel heavy-metal complexing peptides was isolated from plant cell suspension cultures; the structure of the peptides was established as (gamma -glutamic acid-cysteine)n-glycine (n = 3 to 7). These peptides appear upon induction of plant cells with heavy metals and represent the principal metal-binding activities in the cells. The name phytochelatin is proposed for this new class of

Erwin Grill; Ernst-L. Winnacker; Meinhart H. Zenk

1985-01-01

421

Heavy metal cation retention by unconventional sorbents (red muds and fly ashes)  

Microsoft Academic Search

Toxic heavy metals, i.e. copper (II), lead (II) and cadmium (II), can be removed from water by metallurgical solid wastes, i.e. bauxite waste red muds and coal fly ashes acting as sorbents. These heavy-metal-loaded solid wastes may then be solidified by adding cement to a durable concrete mass assuring their safe disposal. Thus, toxic metals in water have been removed

Re?at Apak; Esma Tütem; Mehmet Hügül; Jülide Hizal

1998-01-01

422

Microbial Communities in Long-Term Heavy Metal Contaminated Ombrotrophic Peats  

Microsoft Academic Search

High concentrations of heavy metals are known to be toxic to many soil organisms. The effects of long-term exposure to lower\\u000a levels of metals on the soil microbial community are, however, less well understood. The southern Pennines of the U.K. are\\u000a characterised by expanses of ombrotrophic peat soils that have experienced deposition of high levels of heavy metals since\\u000a the

Patricia E. Linton; Laura Shotbolt; Andrew D. Thomas

2007-01-01

423

The influence of soil heavy metals pollution on soil microbial biomass, enzyme activity, and community composition near a copper smelter  

Microsoft Academic Search

The environmental risk of heavy metal pollution is pronounced in soils adjacent to large industrial complexes. It is important to investigate the functioning of soil microorganisms in ecosystems exposed to long-term contamination by heavy metals. We studied the potential effects of heavy metals on microbial biomass, activity, and community composition in soil near a copper smelter in China. The results

YuanPeng Wang; JiYan Shi; Hui Wang; Qi Lin; XinCai Chen; YingXu Chen

2007-01-01

424

Heavy metal toxicity to microbe-mediated ecologic processes: A review and potential application to regulatory policies  

Microsoft Academic Search

Microorganisms are sensitive to heavy metal pollution as are other components of the biota. However, most studies on the interactions between microbes and heavy metals have been conducted in synthetic media or in altered (e.g., sterilized) environmental samples and usually have used only single species. Few studies have evaluated the effects of heavy metals on the activities of natural heterogeneous

H. Babich; G. Stotzky

1985-01-01

425

Usefulness of NIR spectroscopy for the estimation of the mineral composition and texture of soils and heavy metal uptake  

Microsoft Academic Search

The accumulation of heavy metals in soils from different sources (atmospheric deposition, agricultural practices, urban-industrial activities, etc.) is of a great environmental concern. In this sense, there is a consensus in the literature that the total heavy metals in soil are not a suitable tool for risk assessment regarding heavy metal mobility and bioavailability. Several approaches have been proposed to

J. M. Soriano-Disla; I. Gómez; M. M. Jordán; C. Guerrero; J. Navarro-Pedreño; S. Meseguer; T. Sanfeliu

2009-01-01

426

Heavy metal concentrations in soils and accumulation in plants growing in a deserted slag dumpsite in Nigeria  

Microsoft Academic Search

Early detection and remediation of heavy metals in soil and vegetation will ameliorate serious threats posed to human existence. An auto battery manufacturing company dumped slag containing proportion of heavy metals in an hectare of land at Lalupon, Ibadan, Nigeria. The extent of contamination of soil by heavy metals and their accumulation in plants around the abandoned slag was studied.

Mary B. Ogundiran; Oladele Osibanjo

2008-01-01

427

INTERPRETING THE RESULTS OF SOIL TESTS FOR HEAVY METALS Vern Grubinger and Don Ross, University of Vermont  

E-print Network

of Vermont Agricultural soils normally contain low background levels of heavy metals. Contamination from industrial activities or byproducts can increase the natural levels of heavy metals in soil, creating toxicity of a heavy metal will be affected by soil texture, organic matter, and pH. The health effects

Hayden, Nancy J.

428

Heavy metal contamination and their distribution in different size fractions of the surficial sediment of Haihe River, China  

Microsoft Academic Search

Heavy metal contamination and their distribution in different size fractions of the surficial sediment in Haihe River, China have been investigated. These results reveal that the heavy metal contamination of Haihe River is closely related to the contaminating sources along the river and has the order: Cd > Cu > Pb > Cr. The contents of these heavy metals in the sediment of Haihe River are

Li Liu; Fasheng Li; Daiqun Xiong; Cunyi Song

2006-01-01

429

Heavy Metal Exposure Affects the Humoral Immune Response in a Free-Living Small Songbird, the Great Tit ( Parus major )  

Microsoft Academic Search

Although many studies have investigated possible effects of heavy metal contamination on components of the immune system in captive birds, studies on the effects of chronic exposure to heavy metals on the immune system of free-living birds are rare. Therefore we studied the effect of heavy metal exposure on the humoral immune responsiveness in free-living great tit (Parus major) populations

Tinne Snoeijs; Tom Dauwe; Rianne Pinxten; Frans Vandesande; Marcel Eens

2004-01-01

430

Effects of heavy metals on benthic macroinvertebrate communities in New Zealand streams  

SciTech Connect

The authors performed chemical analyses of heavy metals in water and periphyton, toxicity tests with Daphnia magna and an indigenous mayfly (Deleatidium sp.), and field surveys of benthic macroinvertebrates to estimate the degree of metal pollution in three catchments in the Coromandel Peninsula of New Zealand. Good agreement was found between toxicity tests and measures of benthic community structure, particularly at stations with the highest metal levels. Responses of benthic communities at stations with low or moderate levels of metal contamination were variable and were probably confounded by factors other than heavy metals. Effects of heavy metals on benthic communities in New Zealand streams were similar to those reported for metal-polluted streams in North America and Europe, suggesting that responses to metal contamination are predictable. Abundance and species richness of mayflies, number of taxa in the orders Ephemeroptera, Plecoptera, and Trichoptera, and total taxonomic richness were the best indicators of heavy metals in New Zealand streams. In contrast, the quantitative macroinvertebrate community index (QMCI), a biotic index proposed for assessing effects of organic enrichment in New Zealand streams, could not distinguish between reference and metal-polluted streams. The poor performance of the QMCI was primarily due to incorrect tolerance scores for some taxa to heavy metals. Because of concerns regarding the subjective assignment of tolerance values to species, the authors recommend that tolerance values for dominant species in New Zealand streams should be verified experimentally in stream microcosms.

Hickey, C.W. [National Inst. of Water and Atmospheric Research, Hamilton (New Zealand); Clements, W.H. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Fishery and Wildlife Biology

1998-11-01

431

Heavy metal vaporization and abatement during thermal treatment of modified wastes.  

PubMed

This study examines the vaporization percentage and partitioning of heavy metals Cd, Pb and Zn during thermal treatment of wastes with added PVC, heavy metals or phosphate, and the efficiency of sorbents for removal of these metallic compounds in flue gas of an industrial solid waste incinerator. Firstly, vaporization experiments were carried out to determine the behavior of heavy metals during combustion under various conditions (type of waste, temperature, presence of chloride or phosphate ...). The experimental results show relatively high vaporization percentage of metallic compounds within fly ash and limestone matrix while heavy metals within sediments treated with phosphoric acid are less volatile. Vaporization of metals increases with increasing temperature and with chloride addition. The thermal behavior of the selected heavy metals and their removal by sorbents (sodium bicarbonate, activated carbon) was also studied in an industrial solid waste incinerator. These pilot scale experiments confirm that heavy metals are concentrated in fly ashes and cyclone residues, thus effectively controlling their release to the atmosphere. PMID:17467894

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

2007-09-30

432

Managing heavy metal toxicity stress in plants: biological and biotechnological tools.  

PubMed

The maintenance of ion homeostasis in plant cells is a fundamental physiological requirement for sustainable plant growth, development and production. Plants exposed to high concentrations of heavy metals must respond in order to avoid the deleterious effects of heavy metal toxicity at the structural, physiological and molecular levels. Plant strategies for coping with heavy metal toxicity are genotype-specific and, at least to some extent, modulated by environmental conditions. There is considerable interest in the mechanisms underpinning plant metal tolerance, a complex process that enables plants to survive metal ion stress and adapt to maintain growth and development without exhibiting symptoms of toxicity. This review briefly summarizes some recent cell biological, molecular and proteomic findings concerning the responses of plant roots to heavy metal ions in the rhizosphere, metal ion-induced reactions at the cell wall-plasma membrane interface, and various aspects of heavy metal ion uptake and transport in plants via membrane transporters. The molecular and genetic approaches that are discussed are analyzed in the context of their potential practical applications in biotechnological approaches for engineering increased heavy metal tolerance in crops and other useful plants. PMID:24333465

Ove?ka, M; Taká?, T

2014-01-01

433

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

...of spent nuclear fuel containing 1,000 metric tons of heavy metal (MTHM) exposed...burnup between 25,000 megawatt-days per metric ton of heavy metal (MWd/MTHM) and...adequate to accurately determine the original metric tons of heavy metal in the...

2014-07-01

434

Concentrations of selected heavy metals in benthic diatoms and sediment in the Westerschelde Estuary  

SciTech Connect

In recent years considerable data have been compiled on heavy metal levels in biota in marine and estuarine environments. With respect to the fauna, much information is available on accumulation and effects of heavy metals in birds, fish and benthic macrofauna. Accumulation of heavy metals in aquatic flora has been studied mostly in benthic macroalgae, in particular in relation to the use as a biological monitor. The response of planktonic algal species to heavy metals has been studied extensively in cultured populations. Also. heavy metal concentrations in natural plankton have been studied. As far as we know, very few data are available on the concentrations of heavy metals in the lowest benthic trophic level, the benthic microflora. It is a major food supply for numerous intertidal species, so it is obvious that microflora might play an important role in the accumulation of contaminants through coastal food chains. The aim of this research was to adjust a recently developed collection technique for benthic diatoms so that it is suitable for large-scale field studies. The method was then used to assess the concentration of the heavy metals Cd, Cu, Pb and Zn in benthic diatoms and sediments along an estuarine gradient. 18 refs., 2 figs., 1 tab.

Absil, M.C.P.; Scheppingen, Y. van [Netherlands Inst. of Ecology, Vierstraat (Netherlands)] [Netherlands Inst. of Ecology, Vierstraat (Netherlands)

1996-12-31

435

Heavy metals in seawater, sediments, and biota from the coastal area of Yancheng City, China.  

PubMed

A systematic investigation was carried out to analyze the concentration levels of heavy metals in sample seawater, sediments, and biota collected from the coastal area of Yancheng City in Jiangsu Province, China. The authors assessed the impact of these heavy metals in different environmental samples in terms of potential risks to ecology and also to the human population exposed to this area. In addition, a further investigation was carried out to test the toxicity to early-life-stage zebrafish (Danio rerio) of selected samples that were considered to pose higher levels of potential risks to ecology or human health. Chemical analysis showed relatively higher concentrations of heavy metals in the seawater and biota samples collected from Xiangshui County and Binhai County, China. The heavy metal concentrations in different samples collected from the close vicinity of Dafeng Port, China, were also considerable. In all seawater and sediment samples, heavy metals showed a relatively moderate level of risk to ecological species; for consumption of marine organisms, heavy metals had adverse impacts on human health. Toxicity assessment indicated that the selected environmental samples or their extracts had significant toxicity to zebrafish early-life stages, including lethality, teratogenicity, and hatching delay (or advance). Thus the present study provides highly useful and important information on heavy metal pollution in Jiangsu Province. PMID:24619970

Fu, Jie; Wang, Hui; Billah, Shah M Reduwan; Yu, Hongxia; Zhang, Xiaowei

2014-08-01

436

Heavy metal extraction from PCB wastewater treatment sludge by sulfuric acid.  

PubMed

Heavy metals contaminated wastewater sludge is classified as hazardous solid waste and needs to be properly treated to prevent releasing heavy metals to the environment. In this study, the wastewater treatment sludge from a printed circuit board manufacturing plant was treated in a batch reactor by sulfuric acid to remove the contained heavy metals. The effects of sulfuric acid concentration and solid to liquid ratio on the heavy metal removal efficiencies were investigated. The experimental results showed that the total and individual heavy metal removal efficiencies increased with increasing sulfuric acid concentration, but decreased with increasing solid to liquid ratio. A mathematical model was developed to predict the residual sludge weights at varying sulfuric concentrations and solid to liquid ratios. The trivalent heavy metal ions, iron and chromium were more difficult to be removed than the divalent ions, copper, zinc, nickel, and cadmium. For 5 g/L solid to liquid ratio, more than 99.9% of heavy metals can be removed from the sludge by treating with 0.5M sulfuric acid in 2h. PMID:20079970

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

2010-05-15

437

[Removal of heavy metals from extract of Angelica sinensis by EDTA-modified chitosan magnetic adsorbent].  

PubMed

The concentrations of heavy metals in the extracting solutions of traditional Chinese medicine are usually very low. Furthermore, a vast number of organic components contained in the extracting solutions would be able to coordinate with heavy metals, which might lead to great difficulty in high efficient removal of them from the extracting solutions. This paper was focused on the removal of heavy metals of low concentrations from the extracting solution of Angelica sinensis by applying an EDTA-modified chitosan magnetic adsorbent (EDTA-modified chitosan/SiO2/Fe3O4, abbreviated as EDCMS). The results showed that EDCMS exhibited high efficiency for the removal of heavy metals, such as Cu, Cd and Pb, e.g. the removal percentage of Cd and Pb reached 90% and 94.7%, respectively. Besides, some amounts of other heavy metals like Zn and Mn were also removed by EDCMS. In addition, the total solid contents, the amount of ferulic acid and the HPLC fingerprints of the extracting solution were not changed significantly during the heavy metal removal process. These results indicate that EDCMS may act as an applicable and efficient candidate for the removal of heavy metals from the extracting solution of A. sinensis. PMID:24494559

Ren, Yong; Sun, Ming-Hui; Peng, Hong; Huang, Kai-Xun

2013-11-01

438

Multivariate-Statistical Assessment of Heavy Metals for Agricultural Soils in Northern China  

PubMed Central

The study evaluated eight heavy metals content and soil pollution from agricultural soils in northern China. Multivariate and geostatistical analysis approaches were used to determine the anthropogenic and natural contribution of soil heavy metal concentrations. Single pollution index and integrated pollution index could be used to evaluate soil heavy metal risk. The results show that the first factor explains 27.3% of the eight soil heavy metals with strong positive loadings on Cu, Zn, and Cd, which indicates that Cu, Zn, and Cd are associated with and controlled by anthropic activities. The average value of heavy metal is lower than the second grade standard values of soil environmental quality standards in China. Single pollution index is lower than 1, and the Nemerow integrated pollution index is 0.305, which means that study area has not been polluted. The semivariograms of soil heavy metal single pollution index fitted spherical and exponential models. The variable ratio of single pollution index showed moderately spatial dependence. Heavy metal contents showed relative safety in the study area. PMID:24892058

Yang, Pingguo; Yang, Miao; Mao, Renzhao; Shao, Hongbo

2014-01-01

439

Heavy metal removal from aqueous solution in sequential fluidized-bed reactors.  

PubMed

In this study, the sequential fluidized bed reactors (FBRs), were used to remove heavy metals including, Cu, Pb, and Ni, from synthetic wastewater. Heavy metals were removed through crystallization of metal carbonate and hydroxide precipitates on the surface of sand grains. The results showed that the influent metal concentration limits in the sequential FBRs were higher than those in the vertical FBRs. The removal efficiency for Cu, Pb, and Ni reached 96%, 93%, and 98% when the influent concentrations were 250 mg l(-1), 130 mg l(-1) and 130 mg l(-1), respectively. The pH value in the effluent of the FBR ranged from 8.7 to 9.1. The amount of metal coated onto the sand surface was determined and it was found that most of the metal ions were collected in the first reactor. The mechanism of heavy metal removal in the sequential FBRs concluded crystallization and filtration. PMID:16372569

Lee, C I; Yang, W F

2005-12-01

440

Chitosan-based biosorbents: modification and application for biosorption of heavy metals and radionuclides.  

PubMed

Heavy metal pollution is a serious environmental problem in the world, especially in developing countries. Among different treatment technologies, biosorption seems a promising alternative method. Chitosan-based biosorbents are potential and effective for heavy metal removal from aqueous solution. The preparation and characterization of the natural polymer chitosan, modified chitosan and chitosan composites, and their application for the removal or recovery of toxic heavy metals, precious metals and radionuclides from wastewater were introduced. Chitosan structures and their properties, chitosan modifications (physical conditioning and chemical modification), blends and composites as well as the metal sorption by chitosan-based biosorbents were briefly presented. The metal sorption capacities, influence of intrinsic nature of metal ions, pH and contact time, desorbing agents, isotherm and kinetics models, biosorption mechanisms were discussed. PMID:24461334

Wang, Jianlong; Chen, Can

2014-05-01

441

Heavy metal ions affecting the removal of polycyclic aromatic hydrocarbons by fungi with heavy-metal resistance.  

PubMed

The co-occurrence of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) is very common in contaminated environments. It is of paramount importance and great challenge to exploit a bioremediation to remove PAHs in these environments with combined pollution. We approached this question by probing the influence of HMs coexisting with PAHs on the removal of PAHs by Acremonium sp. P0997 possessing metal resistance. A removal capability for naphthalene, fluorene, phenanthrene, anthracene, and fluoranthenepresentalone (98.6, 99.3, 89.9, 60.4, and 70 %, respectively) and in a mixture (96.9, 71.8, 67.0, 85.0, and 87.9 %, respectively) was achieved in mineral culture inoculated with Acremonium sp. P0997, and this strain also displayed high resistance to the individual HMs (Mn(2+), Fe(2+), Zn(2+), Cu(2+), Al(3+), and Pb(2+)). The removal of individual PAHs existing in a mixture was differently affected by the separately tested HMs. Cu(2+)enhanced the partition process of anthracene to dead or alive mycelia and the contribution of the biosorption by this strain but imposed a little negative influence on the contribution of biodegradation to the total removal of anthracene individually in a culture. However, Mn(2+) had an inhibitory effect on the partition process of anthracene to dead or alive mycelia and decreased the contributions of both biosorption and biodegradation to the total anthracene removal. This work showcased the value of fungi in bioremediation for the environments with combined pollution, and the findings have major implications for the bioremediation of organic pollutants in metal-organic mixed contaminated sites. PMID:25077776

Ma, Xiao-Kui; Ling Wu, Ling; Fam, Hala

2014-12-01

442

Correlation analyses on binding behavior of heavy metals with sediment matrices.  

PubMed

This article presents the amounts of heavy metals bound to the sediment matrices (carbonates, Fe-oxides, Mn-oxides, and organic matter), the correlations between any two heavy-metal binding fractions, and the correlations between sediment matrices and their heavy-metal binding fractions. Data consisted of 313 sets obtained from five main rivers (located in southern Taiwan) were analyzed by statistical methods. Among six heavy metals analyzed (Zn, Cu. Pb, Ni, Cr, and Co), the statistical results show that Zn is primarily bound to organic matter, and Cr is primarily bound to Fe-oxides. Principal component analysis (PCA) and correlation analysis (CA) result in significant correlations between carbonates bound Ni and carbonates bound Cr, Fe-oxides bound Ni and Fe-oxides bound Cr, and Mn-oxides bound Cu and Mn-oxides bound Cr. From linear regression results, the levels of the six heavy metals bound to either organic matter or Fe-oxides is moderately dependent on the contents of organic matter or Fe-oxides, especially true for Cr and Pb. According to slope values of linear regression, Cu and Cr have the highest specific binding amounts (SBA) to organic matter and Fe-oxides, respectively. A significant correlation between organic matter and organically bound heavy metals implied that organic matter contained in the sediments of the Potzu river and the Yenshui river can be adequately used as a normalizing agent. However, the six heavy metals bound to either carbonates or Mn-oxides do not correlate with carbonates or Mn-oxides. The obtained results also imply that competitions of various sediment phases in association with heavy metals occur, and organic matter and Fe-oxides are more accessible to heavy metals than other sediment phases. PMID:11394776

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

2001-07-01

443

[Distribution of heavy metals in Xiangsi River valley of Tongling, China].  

PubMed

The Xiangsi River valley was selected to study the distribution of heavy metals in mining area. Waste rocks, soils, sediments and waters of Xiangsi River valley were sampled. The concentrations of Cu, Pb, Zn, Cd, Cr, As and Hg were analyzed. The possibility of generating acid drainage of the waste rocks was studied. Meanwhile, the speciation of Pb and Cr in waste rocks was analyzed by the five-step sequential chemical extract method developed by F?rtsner. And then the distribution of heavy metals in various samples was summarized, and the ecological risk of heavy metals in mining area was discussed. The results indicated that the waste rocks of Fenghuangshan copper mine upriver barely generated acid mine drainage (AMD). But the waste rocks of Xinqiao pyrite mine in the middle area generated AMD. The content of sulfide mineral rich of heavy metals was lower and the content of CaO was higher in the waste rocks of Fenghuangshan copper mine, resulting in the different AMD generation ability. The contents of heavy metals in waste rocks were higher, and the deoxidization of Pb and Cr was positively correlated with their concentrations in waste rocks. The results indicated that heavy metals in waste rocks would be most likely dissolved in AMD and then contaminate the environment. There was obvious regularity in the distributions of heavy metals in soils, sediments and waters of Xiangsi river valley. The concentrations of heavy metals upriver were lower than those of corresponding national standards and elements background values. But there was obvious heavy metal contamination in the middle area. It was shown that the mining activities of Xinqiao pyrite mine in the middle area had ecological harm to the surrounding environment. And mining enterprises should pay attention to the emissions of mining wastes and the treatment of AMD. PMID:25338367

Chen, Li-Wei; Xu, Xiao-Chun; Wang, Jun; Chen, Fang

2014-08-01

444

Vitrification of MSWI Fly Ash by Thermal Plasma Melting and Fate of Heavy Metals  

NASA Astrophysics Data System (ADS)

Municipal solid waste incinerator (MSWI) fly ash with high basicity (about 1.68) was vitrified in a thermal plasma melting furnace system. Through the thermal plasma treatment, the vitrified product (slag) with amorphous dark glassy structure was obtained, and the leachability of hazardous metals in slag was significantly reduced. Meanwhile, it was found that the cooling rate affects significantly the immobility of heavy metals in slag. The mass distribution of heavy metals (Zn, Cd, Cr, Pb, As, Hg) was investigated in residual products (slag, secondary residues and flue gas), in order to analyze the behavior of heavy metals in thermal plasma atmosphere. Heavy metal species with low boiling points accounting for the major fraction of their input-mass were adsorbed in secondary residues by pollution abatement devices, while those with high boiling points tended to be encapsulated in slag.

Ni, Guohua; Zhao, Peng; Jiang, Yiman; Meng, Yuedong

2012-09-01

445

Wireless electrosampling of heavy metals for stripping analysis with bismuth-based janus particles.  

PubMed

In this contribution, a wireless method for the electrolytic sampling of heavy metals at special bismuth-modified particles is presented. For the first time, glassy carbon beads were asymmetrically modified with bismuth using bipolar electrochemistry. The resulting chemically asymmetric beads, so-called Janus particles, could be employed for the wireless electroaccumulation of heavy metal ions in the bismuth film. The qualitative and quantitative aspects of this concept have been studied by using anodic stripping voltammetry with Cd(2+) and Pb(2+) as the model ions. Different experimental and instrumental parameters have been optimized; among others, the concentration of Bi(3+) ions, the deposition conditions for the bismuth-film, and the accumulation time of the target heavy metals. The developed concept could be applied to the transfer of heavy metal ions from a solution into a confined space without need to electrically connect the collector (electrode), thus representing an interesting new approach for trace metal analysis in small volumes. PMID:25335114

Sopha, Hanna; Roche, Jérome; Svancara, Ivan; Kuhn, Alexander

2014-11-01

446

Interactions between heavy metals and photosynthetic materials studied by optical techniques.  

PubMed

In this work studies on rapid inhibitory interactions between heavy metals and photosynthetic materials at different organization levels were carried out by optical assay techniques, investigating the possibility of applications in the heavy metal detection field. Spinach chloroplasts, thylakoids and Photosystem II proteins were employed as biotools in combination with colorimetric assays based on dichlorophenol indophenole (DCIP) photoreduction and on fluorescence emission techniques. It was found that copper and mercury demonstrated a strong and rapid photosynthetic activity inhibition, that varied from proteins to membranes, while other metals like nickel, cobalt and manganese produced only slight inhibition effects on all tested photosynthetic materials. By emission measurements, only copper was found to rapidly influence the photosynthetic material signals. These findings give interesting information about the rapid effects of heavy metals<