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Sample records for heavy metal mthm

  1. Heavy Metal.

    ERIC Educational Resources Information Center

    Shoemaker, W. Lee

    1998-01-01

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

  2. Mutagenicity of heavy metals

    SciTech Connect

    Wong, P.K.

    1988-04-01

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

  3. Mutagenicity of heavy metals

    SciTech Connect

    Wong, P.K. )

    1988-05-01

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

  4. Biosorption of heavy metals

    SciTech Connect

    Volesky, B. |; Holan, Z.R.

    1995-05-01

    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.

  5. Plants absorb heavy metals

    SciTech Connect

    Parry, J.

    1995-02-01

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

  6. 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...

  7. 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...

  8. Heavy Metal Pumps in Plants

    SciTech Connect

    Harper, J.F.

    2000-10-01

    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.

  9. Heavy Metal Stars

    NASA Astrophysics Data System (ADS)

    2001-08-01

    thereafter dies as a burnt-out, dim "white dwarf" . Stars with masses between 0.8 and 8 times that of the Sun are believed to evolve to AGB-stars and to end their lives in this particular way. At the same time, they produce beautiful nebulae like the "Dumbbell Nebula". Our Sun will also end its active life this way, probably some 7 billion years from now. Low-metallicity stars The detailed understanding of the "s-process" and, in particular, where it takes place inside an AGB-star, has been an area of active research for many years. Current state-of-the-art computer-based stellar models predict that the s-process should be particularly efficient in stars with a comparatively low content of metals ("metal-poor" or "low-metallicity" stars) . In such stars - which were born at an early epoch in our Galaxy and are therefore quite old - the "s-process" is expected to effectively produce atomic nuclei all the way up to the most heavy, stable ones, like Lead (atomic number 82 [2]) and Bismuth (atomic number 83) - since more neutrons are available per Iron-seed nucleus when there are fewer such nuclei (as compared to the solar composition). Once these elements have been produced, the addition of more s-process neutrons to those nuclei will only produce unstable elements that decay back to Lead. Hence, when the s-process is sufficiently efficient, atomic nuclei with atomic numbers around 82, that is, the Lead region, just continue to pile up. As a result, when compared to stars with "normal" abundances of the metals (like our Sun), those low-metallicity stars should thus exhibit a significant "over-abundance" of those very heavy elements with respect to Iron, in particular of Lead . Looking for Lead Direct observational support for this theoretical prediction would be the discovery of some low-metallicity stars with a high abundance of Lead. At the same time, the measured amounts of all the heavy elements and their relative abundances would provide very valuable information and

  10. Process for removing heavy metal compounds from heavy crude oil

    DOEpatents

    Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.

    1991-01-01

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

  11. Phycoremediation of heavy metals using transgenic microalgae.

    PubMed

    Rajamani, Sathish; Siripornadulsil, Surasak; Falcao, Vanessa; Torres, Moacir; Colepicolo, Pio; Sayre, Richard

    2007-01-01

    Microalgae account for most of the biologically sequestered trace metals in aquatic environments. Their ability to adsorb and metabolize trace metals is associated with their large surface:volume ratios, the presence of high-affinity, metal-binding groups on their cell surfaces, and efficient metal uptake and storage systems. Microalgae may bind up to 10% of their biomass as metals. In addition to essential trace metals required for metabolism, microalgae can efficiently sequester toxic heavy metals. Toxic heavy metals often compete with essential trace metals for binding to and uptake into cells. Recently, transgenic approaches have been developed to further enhance the heavy metal specificity and binding capacity of microalgae with the objective of using these microalgae for the treatment of heavy metal contaminated wastewaters and sediments. These transgenic strategies have included the over expression of enzymes whose metabolic products ameliorate the effects of heavy metal-induced stress, and the expression of high-affinity, heavy metal binding proteins on the surface and in the cytoplasm of transgenic cells. The most effective strategies have substantially reduced the toxicity of heavy metals allowing transgenic cells to grow at wild-type rates in the presence of lethal concentrations of heavy metals. In addition, the metal binding capacity of transgenic algae has been increased five-fold relative to wild-type cells. Recently, fluorescent heavy metal biosensors have been developed for expression in transgenic Chlamydomonas. These fluorescent biosensor strains can be used for the detection and quantification of bioavailable heavy metals in aquatic environments. The use of transgenic microalgae to monitor and remediate heavy metals in aquatic environments is not without risk, however. Strategies to prevent the release of live microalgae having enhanced metal binding properties are described. PMID:18161494

  12. The Heavy Metal Subculture and Suicide.

    ERIC Educational Resources Information Center

    Stack, Steven; And Others

    1994-01-01

    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.…

  13. Industrial hygiene of selected heavy metals

    SciTech Connect

    Woodring, J.L.

    1993-08-01

    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.

  14. Heavy metals in Antarctic organisms

    SciTech Connect

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

    1997-02-01

    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.

  15. Hazards of heavy metal contamination.

    PubMed

    Järup, Lars

    2003-01-01

    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 been known for a long time, exposure to heavy metals continues, and is even increasing in some parts of the world, in particular in less developed countries, though emissions have declined in most developed countries over the last 100 years. Cadmium compounds are currently mainly used in re-chargeable nickel-cadmium batteries. Cadmium emissions have increased dramatically during the 20th century, one reason being that cadmium-containing products are rarely re-cycled, but often dumped together with household waste. Cigarette smoking is a major source of cadmium exposure. In non-smokers, food is the most important source of cadmium exposure. Recent data indicate that adverse health effects of cadmium exposure may occur at lower exposure levels than previously anticipated, primarily in the form of kidney damage but possibly also bone effects and fractures. Many individuals in Europe already exceed these exposure levels and the margin is very narrow for large groups. Therefore, measures should be taken to reduce cadmium exposure in the general population in order to minimize the risk of adverse health effects. The general population is primarily exposed to mercury via food, fish being a major source of methyl mercury exposure, and dental amalgam. The general population does not face a significant health risk from methyl mercury, although certain groups with high fish consumption may attain blood levels associated with a low risk of neurological damage to adults. Since there is a risk to the fetus in particular, pregnant women should avoid a high intake of certain fish, such as shark, swordfish and

  16. Bioremoval of heavy metals by bacterial biomass.

    PubMed

    Aryal, Mahendra; Liakopoulou-Kyriakides, Maria

    2015-01-01

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

  17. Heavy Metal Music and Adolescent Suicidal Risk.

    ERIC Educational Resources Information Center

    Lacourse, Eric; Claes, Michel; Villeneuve, Martine

    2001-01-01

    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…

  18. Heavy Metal, Religiosity, and Suicide Acceptability.

    ERIC Educational Resources Information Center

    Stack, Steven

    1998-01-01

    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)

  19. 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...

  20. Effect of heavy metals on soil fungi

    NASA Astrophysics Data System (ADS)

    Sosak-Świderska, Bożena

    2010-05-01

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

  1. Stabilization of heavy metals in sludge ceramsite.

    PubMed

    Xu, G R; Zou, J L; Li, G B

    2010-05-01

    This paper attempts to investigate the stabilization behaviours of heavy metals in ceramsite made from wastewater treatment sludge (WWTS) and drinking-water treatment sludge (DWTS). Leaching tests were conducted to find out the effects of sintering temperature, (Fe(2)O(3) + CaO + MgO)/(SiO(2) + Al(2)O(3)) (defined as F/SA ratios), pH, and oxidative condition. Results show that sintering exhibits good binding capacity for Cd, Cr, Cu, and Pb in ceramsite and leaching contents of heavy metals will not change above 1000 degrees C. The main crystalline phases in ceramsite sintered at 1000 degrees C are kyanite, quartz, Na-Ca feldspars, sillimanite, and enstatite. The main compounds of heavy metals are crocoite, chrome oxide, cadmium silicate, and copper oxide. Leaching contents of Cd, Cu, and Pb increase as the F/SA ratios increase. Heavy metals in ceramsite with variation of F/SA ratios are also in same steady forms, which prove that stronger chemical bonds are formed between these heavy metals and the components. Leaching contents of heavy metals decrease as pH increases and increase as H(2)O(2) concentration increases. The results indicate that when subjected to rigorous leaching conditions, the crystalline structures still exhibit good chemical binding capacity for heavy metals. In conclusion, it is environmentally safe to use ceramsite in civil and construction fields. PMID:20219229

  2. Heavy metal contamination from geothermal sources.

    PubMed

    Sabadell, J E; Axtmann, R C

    1975-12-01

    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

  3. Removal of heavy metals from waste streams

    SciTech Connect

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

    1988-07-19

    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.

  4. Heavy metal contamination from geothermal sources.

    PubMed Central

    Sabadell, J E; Axtmann, R C

    1975-01-01

    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

  5. Heavy metals and living systems: An overview

    PubMed Central

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

    2011-01-01

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

  6. Heavy metal removal and recovery using microorganisms

    SciTech Connect

    Wilde, E.W. ); Benemann, J.R. , Pinole, CA )

    1991-02-01

    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.

  7. Heavy Metal Risk Management: Case Analysis

    PubMed Central

    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

    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

  8. Ion Mobility Spectrometry of Heavy Metals.

    PubMed

    Ilbeigi, Vahideh; Valadbeigi, Younes; Tabrizchi, Mahmoud

    2016-07-19

    A simple, fast, and inexpensive method was developed for detecting heavy metals via the ion mobility spectrometry (IMS) in the negative mode. In this method, Cl(-) ion produced by the thermal ionization of NaCl is employed as the dopant or the ionizing reagent to ionize heavy metals. In practice, a solution of mixed heavy metals and NaCl salts was directly deposited on a Nichrome filament and electrically heated to vaporize the salts. This produced the IMS spectra of several heavy-metal salts, including CdCl2, ZnSO4, NiCl2, HgSO4, HgCl2, PbI2, and Pb(Ac)2. For each heavy metal (M), one or two major peaks were observed, which were attributed to M·Cl(-) or [M·NaCl]Cl(-)complexes. The method proved to be useful for the analysis of mixed heavy metals. The absolute detection limits measured for ZnSO4 and HgSO4 were 0.1 and 0.05 μg, respectively. PMID:27321408

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

    SciTech Connect

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

    1983-06-01

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

  10. ANALYSIS OF HEAVY METALS IN STORMWATER

    EPA Science Inventory

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

  11. The remediation of heavy metals contaminated sediment.

    PubMed

    Peng, Jian-Feng; Song, Yong-Hui; Yuan, Peng; Cui, Xiao-Yu; Qiu, Guang-Lei

    2009-01-30

    Heavy metal contamination has become a worldwide problem through disturbing the normal functions of rivers and lakes. Sediment, as the largest storage and resources of heavy metal, plays a rather important role in metal transformations. This paper provides a review on the geochemical forms, affecting factors and remediation technologies of heavy metal in sediment. The in situ remediation of sediment aims at increasing the stabilization of some metals such as the mobile and the exchangeable fractions; whereas, the ex situ remediation mainly aims at removing those potentially mobile metals, such as the Mn-oxides and the organic matter (OM) fraction. The pH and OM can directly change metals distribution in sediment; however oxidation-reduction potential (ORP), mainly through changing the pH values, indirectly alters metals distribution. Mainly ascribed to their simple operation mode, low costs and fast remediation effects, in situ remediation technologies, especially being fit for slight pollution sediment, are applied widely. However, for avoiding metal secondary pollution from sediment release, ex situ remediation should be the hot point in future research. PMID:18547718

  12. Heavy metal contaminants in yerberia shop products.

    PubMed

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

    2013-03-01

    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

  13. Heavy Metal Poisoning and Cardiovascular Disease

    PubMed Central

    Alissa, Eman M.; Ferns, Gordon A.

    2011-01-01

    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

  14. Community Heavy Metal Exposure, San Francisco, California

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

    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.

  15. Heavy metal speciation in the composting process.

    PubMed

    Greenway, Gillian M; Song, Qi Jun

    2002-04-01

    Composting is one of the more efficient and environment friendly methods of solid waste disposal and has many advantages when compared with landfill disposal on which the UK and Ireland are currently heavily dependent. Composting is a very complicated process involving intensive microbial activity and the detailed mechanisms of the process have yet to be fully understood. Metal speciation information can provide an insight into the metal-microbial interaction and would help in the evaluation of the quality of compost. This would facilitate the exploitation of composts in remediation of heavy metal contaminated land. In this work a systematic approach to metal speciation in compost has been taken by applying the three-step method for operationally defined metal speciation of soils and sediments, developed by the European Commission's Standards, Measurement and Testing Programme to monitor the change in metal speciation with time (up to 106 days) for four different waste composting processes. The results have shown that in general metals become less available for the first extraction step as the composting process proceeds. This implies that composting tends to redistribute the metals from more labile forms to more fixed forms which may explain why the application of composts could be useful for with heavy metal contaminated land. There are exceptions to this trend and in some cases, certain metals appear to behave differently depending on the source of the compost. PMID:11993774

  16. Consequential species of heavy metals. Final report

    SciTech Connect

    Yousef, Y.A.; Harper, H.H.; Wiseman, L.; Bateman, M.

    1985-02-01

    Highway stormwater runoff contains significantly higher concentrations of trace metals, particularly Pb, Zn, Cd, Cu, Cr, Fe, and Ni than the water samples from adjacent receiving water bodies. The metals associated with highway runoff tend to be detoxified by the organic content and chemical conditions of natural waters and sediments. Most of the metals are retained by the bottom sediments on a permanent basis if aerobic conditions and high redax-potential (Eh) values are maintained. Retention/detention ponds similar to the Maitland Pond site are very effective in nutrient and heavy metal removal from highway runoff.

  17. Approaches for enhanced phytoextraction of heavy metals.

    PubMed

    Bhargava, Atul; Carmona, Francisco F; Bhargava, Meenakshi; Srivastava, Shilpi

    2012-08-30

    The contamination of the environment with toxic metals has become a worldwide problem. Metal toxicity affects crop yields, soil biomass and fertility. Soils polluted with heavy metals pose a serious health hazard to humans as well as plants and animals, and often requires soil remediation practices. Phytoextraction refers to the uptake of contaminants from soil or water by plant roots and their translocation to any harvestable plant part. Phytoextraction has the potential to remove contaminants and promote long-term cleanup of soil or wastewater. The success of phytoextraction as a potential environmental cleanup technology depends on factors like metal availability for uptake, as well as plants ability to absorb and accumulate metals in aerial parts. Efforts are ongoing to understand the genetics and biochemistry of metal uptake, transport and storage in hyperaccumulator plants so as to be able to develop transgenic plants with improved phytoremediation capability. Many plant species are being investigated to determine their usefulness for phytoextraction, especially high biomass crops. The present review aims to give an updated version of information available with respect to metal tolerance and accumulation mechanisms in plants, as well as on the environmental and genetic factors affecting heavy metal uptake. The genetic tools of classical breeding and genetic engineering have opened the door to creation of 'remediation' cultivars. An overview is presented on the possible strategies for developing novel genotypes with increased metal accumulation and tolerance to toxicity. PMID:22542973

  18. Heavy metal detoxification in eukaryotic microalgae.

    PubMed

    Perales-Vela, Hugo Virgilio; Peña-Castro, Julián Mario; Cañizares-Villanueva, Rosa Olivia

    2006-06-01

    Microalgae are aquatic organisms possessing molecular mechanisms that allow them to discriminate non-essential heavy metals from those essential ones for their growth. The different detoxification processes executed by algae are reviewed with special emphasis on those involving the peptides metallothioneins, mainly the post transcriptionally synthesized class III metallothioneins or phytochelatins. Also, the features that make microalgae suitable organisms technologies specially to treat water that is heavily polluted with metals is discussed. PMID:16405948

  19. Heavy metal mining using microbes.

    PubMed

    Rawlings, Douglas E

    2002-01-01

    The use of acidiphilic, chemolithotrophic iron- and sulfur-oxidizing microbes in processes to recover metals from certain types of copper, uranium, and gold-bearing minerals or mineral concentrates is now well established. During these processes insoluble metal sulfides are oxidized to soluble metal sulfates. Mineral decomposition is believed to be mostly due to chemical attack by ferric iron, with the main role of the microorganisms being to reoxidize the resultant ferrous iron back to ferric iron. Currently operating industrial biomining processes have used bacteria that grow optimally from ambient to 50 degrees C, but thermophilic microbes have been isolated that have the potential to enable mineral biooxidation to be carried out at temperatures of 80 degrees C or higher. The development of higher-temperature processes will extend the variety of minerals that can be commercially processed. PMID:12142493

  20. Bacterial sorption of heavy metals.

    PubMed Central

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

    1989-01-01

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

  1. DECONTAMINATION OF HEAVY METALS WITH BACTERIA

    EPA Science Inventory



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


    ABSTRACT: Our laboratory (Vesper et al. ...

  2. 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...

  3. Heavy Metals and Related Trace Elements.

    ERIC Educational Resources Information Center

    Leland, Harry V.; And Others

    1978-01-01

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

  4. 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...

  5. Superoxide dismutases of heavy metal resistant streptomycetes.

    PubMed

    Schmidt, Astrid; Schmidt, André; Haferburg, Götz; Kothe, Erika

    2007-02-01

    Heavy metal tolerant and resistant strains of streptomycetes isolated from a former uranium mining site were screened for their superoxide dismutase expression. From the strains tolerating high concentrations of different heavy metals, one was selected for its tolerance of concentrations of heavy metals (Ni, Cu, Cd, Cr, Mn, Zn, Fe). This strain, Streptomyces acidiscabies E13, was chosen for the purpose of superoxide dismutase analysis. Gel electrophoresis and activity staining revealed only one each of a nickel (NiSOD) and an iron (FeZnSOD) containing superoxide dismutase as shown by differential enzymatic repression studies. The gene for nickel containing superoxide dismutase, sodN, was cloned and sequenced from this strain. The genomic sequence shows 92.7% nucleotide identity and 96.1% amino acid identity to sodN of S. coelicolor. Expression can be activated by nickel as well as other heavy metals and active enzyme is produced in media lacking nickel but containing copper, iron or zinc. Thus, the selected strain is well suited for further characterization of the enzyme encoded by sodN. PMID:17304620

  6. Heavy metals in the environment

    SciTech Connect

    Storm, G.L.; Fosmire, G.J.; Bellis, E.D.

    1994-05-01

    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.

  7. Minor heavy metal: A review on occupational and environmental intoxication

    PubMed Central

    Wiwanitkit, Viroj

    2008-01-01

    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

  8. Heavy metal tolerance in metal hyperaccumulator plant, Salvinia natans.

    PubMed

    Dhir, B; Srivastava, S

    2013-06-01

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

  9. Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation

    ERIC Educational Resources Information Center

    Forgy, David

    2012-01-01

    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…

  10. Heavy metals and the origin of life

    NASA Astrophysics Data System (ADS)

    Nriagu, J.

    2003-05-01

    The functional value of heavy metals in proto-cells was immense and involved critical roles in catalysis of molecular synthesis, translation, electrical neutrality and conduction, energy capture, cross-linking and precipitation (stabilizers of protective cell walls), and to a limited extent, osmotic pressure control. Metals must have modulated the evolutionary choices of the types of building blocks, such as ribose sugars as a constituent of RNA, or the the chirality and enantiopurity of many biomolecules. The formation of an enclosing membrane led to intracellular prokaryotic life (believed to have originated in an anaerobic environment) and much enhanced control over primary metabolism, the uptake and incorporation of heavy metals and the management of biomolecules (especially RNA, DNA and proteins) that were formed. Cells of the most primitive organisms (archaebacteria) reveal complex mechanisms designed specifically to deal with selective pressures from metal-containing environments including intra- and extra-cellular sequestration, exclusion by cell wall barrier, removal through active efflux pumps, enzymatic detoxification, and reduction in sensitivity of cellular targets to metal ions. Adaptation to metals using a variety of chromosomal, and transposon and plasmid-mediated systems began early in the evolution of life on Earth. Recent studies, however, show that the roles played by many heavy metals have changed over time. Divalent lead, for instance, has relinquished its unique catalytic role in the conversion of carbohydrates into ribose in the prebiotic world. The putative elements that dominated the primordial biochemistry were V, Mo, W, Co, Fe(II) and Ni; with the development of oxygenated atmosphere, these elements gave way to Zn, Cu and Fe(Ill) in their metabolic functions.

  11. Effect of heavy metals on bacterial transport

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Olson, M. S.

    2010-12-01

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

  12. Heavy metal resistance in halophilic Bacteria and Archaea.

    PubMed

    Voica, Doriana Mădălina; Bartha, Laszlo; Banciu, Horia Leonard; Oren, Aharon

    2016-07-01

    Heavy metals are dense chemicals with dual biological role as micronutrients and intoxicants. A few hypersaline environmental systems are naturally enriched with heavy metals, while most metal-contaminated sites are a consequence of human activities. Numerous halotolerant and moderately halophilic Bacteria possess metal tolerance, whereas a few archaeal counterparts share similar features. The main mechanisms underlying heavy metal resistance in halophilic Bacteria and Archaea include extracellular metal sequestration by biopolymers, metal efflux mediated by specific transporters and enzymatic detoxification. Biotransformation of metals by halophiles has implications both for trace metal turnover in natural saline ecosystems and for development of novel bioremediation strategies. PMID:27279625

  13. Environmental impact of mercury and other heavy metals

    NASA Astrophysics Data System (ADS)

    Lindqvist, Oliver

    The environmental impact of heavy metals is reviewed. One significant source of emissions of heavy metals to air is waste incineration. Consumer batteries contributes significantly to this problem, as well as to heavy metal leakage to groundwater from landfill deposits. The situation in Sweden is used as an example to describe how the deposition from the atmosphere still is increasing the load of heavy metals, like mercury, cadmium and lead, in top soils and aquatic sediments. Critical factors and effect levels for Hg, Cd, Pb, Cu, Zn and As are discussed. Specific questions like mercury contents in present battery waste and heavy metal contents in new and future secondary batteries are addressed.

  14. Earthworm contamination by PCBs and heavy metals

    SciTech Connect

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

    1985-01-01

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

  15. Multiple heavy metal removal using an entomopathogenic fungi Beauveria bassiana.

    PubMed

    Gola, Deepak; Dey, Priyadarshini; Bhattacharya, Arghya; Mishra, Abhishek; Malik, Anushree; Namburath, Maneesh; Ahammad, Shaikh Ziauddin

    2016-10-01

    Towards the development of a potential remediation technology for multiple heavy metals [Zn(II), Cu(II), Cd(II), Cr(VI) and Ni(II)] from contaminated water, present study examined the growth kinetics and heavy metal removal ability of Beauveria bassiana in individual and multi metals. The specific growth rate of B. bassiana varied from 0.025h(-1) to 0.039h(-1) in presence of individual/multi heavy metals. FTIR analysis indicated the involvement of different surface functional groups in biosorption of different metals, while cellular changes in fungus was reflected by various microscopic (SEM, AFM and TEM) analysis. TEM studies proved removal of heavy metals via sorption and accumulation processes, whereas AFM studies revealed increase in cell surface roughness in fungal cells exposed to heavy metals. Present study delivers first report on the mechanism of bioremediation of heavy metals when present individually as well as multi metal mixture by entomopathogenic fungi. PMID:27387415

  16. Phytoaccumulation of heavy metals by aquatic plants.

    PubMed

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

    2004-02-01

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

  17. Modeling heavy metal removal in wetlands

    SciTech Connect

    Lung, W.S.; Light, R.N.

    1994-12-31

    Although the use of wetland ecosystems to purify water has gained increased attention only recently, it has been recognized as a wastewater treatment technique for centuries. While considerable research has occurred to quantify the nutrient (nitrogen and phosphorus) removal mechanisms of wetlands, relatively few investigators have focused on the mechanisms of heavy metal removal and uptake by wetland sediments and plants. The quantification of the assimilative capacity of heavy metals by wetland ecosystems is a critical component in the design and use of wetlands for this purpose. A computer model has been developed to simulate the fate and transport of heavy metals introduced to a wetland ecosystem. Modeled water quality variables include phytoplankton biomass and productivity; macrophyte (Nulumbo lutea) biomass; total phosphorus in the water column; dissolved copper in the water column and sediments; particulate copper in the water column and sediments; and suspended solids. These variables directly affect the calculated rate of copper uptake by macrophytes, and the rate of copper recycling as a function of the decomposition of copper-laden biomass litter. The model was calibrated using total phosphorus and chlorophyll a data from the Old Woman Creek Wetland in Ohio. Verification of the model was achieved using data on the copper content of the macrophyte Nelumbo lutea.

  18. Plant rhamnogalacturonan II complexation of heavy metal cations

    DOEpatents

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

    1999-03-02

    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.

  19. Plant rhamnogalacturonan II complexation of heavy metal cations

    DOEpatents

    O'Neill, Malcolm A.; Pellerin, Patrice J. M.; Warrenfeltz, Dennis; Vidal, Stephane; Darvill, Alan G.; Albersheim, Peter

    1999-01-01

    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.

  20. Magnetotactic bacteria: promising biosorbents for heavy metals.

    PubMed

    Zhou, Wei; Zhang, Yanzong; Ding, Xiaohui; Liu, Yan; Shen, Fei; Zhang, Xiaohong; Deng, Shihuai; Xiao, Hong; Yang, Gang; Peng, Hong

    2012-09-01

    Magnetotactic bacteria (MTB), which can orient and migrate along a magnetic line of force due to intracellular nanosized magnetosomes, have been a subject of research in the medical field, in dating environmental changes, and in environmental remediation. This paper reviews the recent development of MTB as biosorbents for heavy metals. Ultrastructures and taxis of MTB are investigated. Adsorptions in systems of unitary and binary ions are highlighted, as well as adsorption conditions (temperature, pH value, biomass concentration, and pretreatments). The separation and desorption of MTB in magnetic separators are also discussed. A green method to produce metal nanoparticles is provided, and an energy-efficient way to recover precious metals is put forward during biosorption. PMID:22763846

  1. Material Removes Heavy Metal Ions From Water

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

    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.

  2. Biosorption of heavy metals by Saccharomyces cerevisiae.

    PubMed

    Volesky, B; May-Phillips, H A

    1995-01-01

    Abundant and common yeast biomass has been examined for its capacity to sequester heavy metals from dilute aqueous solutions. Live and non-living biomass of Saccharomyces cerevisiae differs in the uptake of uranium, zinc and copper at the optimum pH 4-5. Culture growth conditions can influence the biosorbent metal uptake capacity which normally was: living and non-living brewer's yeast: U > Zn > Cd > Cu; non-living baker's yeast: Zn > (Cd) > U > Cu; living baker's yeast: Zn > Cu approximately (Cd) > U. Non-living brewer's yeast biomass accumulated 0.58 mmol U/g. The best biosorbent of zinc was non-living baker's yeast (approximately 0.56 mmol Zn/g). Dead cells of S. cerevisiae removed approximately 40% more uranium or zinc than the corresponding live cultures. Biosorption of uranium by S. cerevisiae was a rapid process reaching 60% of the final uptake value within the first 15 min of contact. Its deposition differing from that of other heavy metals more associated with the cell wall, uranium was deposited as fine needle-like crystals both on the inside and outside of the S. cerevisiae cells. PMID:7765919

  3. Contamination of environment with heavy metals emitted from automotives

    SciTech Connect

    Falahi-Ardakani, A.

    1984-04-01

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

  4. Visualizing plumes of heavy metals and radionuclides

    NASA Astrophysics Data System (ADS)

    Prigiobbe, V.; Liu, T.; Bryant, S. L.; Hesse, M. A.

    2015-12-01

    The understanding of the transport behaviors in porous media resides on the ability to reproduce fundamental phenomena in a lab setting. Experiments with quasi 2D tanks filled with beads are performed to study physical phenomena induced by chemical and fluid dynamic processes. When an alkaline solution containing heavy metals or radionuclides invades a low pH region, mixing due to longitudinal dispersion induces destabilization of the front forming a fast travelling pulse [1]. When the two fluids travel in parallel, instead, mixing induced by transverse dispersion creates a continuous leakage from the alkaline region into the acidic one forming a fast travelling plume [2] (Figure 1). Impact of these phenomena are on aquifers upon leaking of alkaline fluids, rich in heavy metals and radionuclides, from waste storage sites. Here, we report the results from a study where experiments with a quasi 2D tank are performed to analyze the effect of transverse mixing on strontium (Sr2+) transport. To visualize the leaking plume, a fluorescent dye (Fura-2) is added the acidic solution, which has been widely used in biomedical applications [3]. It is the aim of this work to optimize its application under the conditions relevant to this work. Spectrometric measurements of absorption and fluorescence show sensitivity of the dye to the presence of Sr2+ throughout a broad range of pH and Sr2+ concentration (Figure 2). In the absence of Sr2+, no significant absorption and fluorescence was measured, but as Sr2+ was added the relevant peaks increase significantly and sample dilution of tenfold was required to remain within the measuring threshold. These results show a strong sensitivity of the dye to the cation opening the opportunity to use Fura-2 as a tool to visualize heavy metals and radionuclides plumes. References[1] Prigiobbe et al. (2012) GRL 39, L18401. [2] Prigiobbe and Hesse (2015) in preparation. [3] Xu-Friedman and Regehr (2000) J. Neurosci. 20(12) 4414-4422.

  5. Heavy metal adsorption by sulphide mineral surfaces

    NASA Astrophysics Data System (ADS)

    Jean, Gilles E.; Bancroft, G. Michael

    1986-07-01

    The adsorption of aqueous Hg 2+, Pb 2+, Zn 2+ and Cd 2+ complexes on a variety of sulphide minerals has been studied as a function of the solution pH and also as a function of the nature of the ligands in solution. Sulphide minerals are excellent scavengers for these heavy metals. The adsorption is strongly pH dependent, i.e. there is a critical pH at which the adsorption increases dramatically. The pH dependence is related to the hydrolysis of the metal ions. Indirect evidence suggests that the hydrolyzed species are adsorbed directly on the sulphide groups, probably as a monolayer. The results also suggest the presence of MCI n2- n species physisorbed on the adsorbed monolayer. A positive identification of the adsorbed species was not possible using ESCA/XPS.

  6. [Biological activity of selenorganic compounds at heavy metal salts intoxication].

    PubMed

    Rusetskaya, N Y; Borodulin, V B

    2015-01-01

    Possible mechanisms of the antitoxic action of organoselenium compounds in heavy metal poisoning have been considered. Heavy metal toxicity associated with intensification of free radical oxidation, suppression of the antioxidant system, damage to macromolecules, mitochondria and the genetic material can cause apoptotic cell death or the development of carcinogenesis. Organic selenium compounds are effective antioxidants during heavy metal poisoning; they exhibit higher bioavailability in mammals than inorganic ones and they are able to activate antioxidant defense, bind heavy metal ions and reactive oxygen species formed during metal-induced oxidative stress. One of promising organoselenium compounds is diacetophenonyl selenide (DAPS-25), which is characterized by antioxidant and antitoxic activity, under conditions including heavy metal intoxication. PMID:26350735

  7. Toxic heavy metals: materials cycle optimization.

    PubMed Central

    Ayres, R U

    1992-01-01

    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

  8. Heavy metal toxicity and the environment.

    PubMed

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

    2012-01-01

    Heavy metals are naturally occurring elements that have a high atomic weight and a density at least five 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 US 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

  9. Heavy Metals Toxicity and the Environment

    PubMed Central

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

    2013-01-01

    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

  10. Heavy Metal Induced Antibiotic Resistance in Bacterium LSJC7.

    PubMed

    Chen, Songcan; Li, Xiaomin; Sun, Guoxin; Zhang, Yingjiao; Su, Jianqiang; Ye, Jun

    2015-01-01

    Co-contamination of antibiotics and heavy metals prevails in the environment, and may play an important role in disseminating bacterial antibiotic resistance, but the selective effects of heavy metals on bacterial antibiotic resistance is largely unclear. To investigate this, the effects of heavy metals on antibiotic resistance were studied in a genome-sequenced bacterium, LSJC7. The results showed that the presence of arsenate, copper, and zinc were implicated in fortifying the resistance of LSJC7 towards tetracycline. The concentrations of heavy metals required to induce antibiotic resistance, i.e., the minimum heavy metal concentrations (MHCs), were far below (up to 64-fold) the minimum inhibition concentrations (MIC) of LSJC7. This finding indicates that the relatively low heavy metal levels in polluted environments and in treated humans and animals might be sufficient to induce bacterial antibiotic resistance. In addition, heavy metal induced antibiotic resistance was also observed for a combination of arsenate and chloramphenicol in LSJC7, and copper/zinc and tetracycline in antibiotic susceptible strain Escherichia coli DH5α. Overall, this study implies that heavy metal induced antibiotic resistance might be ubiquitous among various microbial species and suggests that it might play a role in the emergence and spread of antibiotic resistance in metal and antibiotic co-contaminated environments. PMID:26426011

  11. Heavy Metal Induced Antibiotic Resistance in Bacterium LSJC7

    PubMed Central

    Chen, Songcan; Li, Xiaomin; Sun, Guoxin; Zhang, Yingjiao; Su, Jianqiang; Ye, Jun

    2015-01-01

    Co-contamination of antibiotics and heavy metals prevails in the environment, and may play an important role in disseminating bacterial antibiotic resistance, but the selective effects of heavy metals on bacterial antibiotic resistance is largely unclear. To investigate this, the effects of heavy metals on antibiotic resistance were studied in a genome-sequenced bacterium, LSJC7. The results showed that the presence of arsenate, copper, and zinc were implicated in fortifying the resistance of LSJC7 towards tetracycline. The concentrations of heavy metals required to induce antibiotic resistance, i.e., the minimum heavy metal concentrations (MHCs), were far below (up to 64-fold) the minimum inhibition concentrations (MIC) of LSJC7. This finding indicates that the relatively low heavy metal levels in polluted environments and in treated humans and animals might be sufficient to induce bacterial antibiotic resistance. In addition, heavy metal induced antibiotic resistance was also observed for a combination of arsenate and chloramphenicol in LSJC7, and copper/zinc and tetracycline in antibiotic susceptible strain Escherichia coli DH5α. Overall, this study implies that heavy metal induced antibiotic resistance might be ubiquitous among various microbial species and suggests that it might play a role in the emergence and spread of antibiotic resistance in metal and antibiotic co-contaminated environments. PMID:26426011

  12. Hydroponic phytoremediation of heavy metals and radionuclides

    SciTech Connect

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

    1998-07-01

    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.

  13. Plant productivity and heavy metal contamination

    SciTech Connect

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

    1990-06-01

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

  14. Intrinsic Instabilities Of Heavy Metal Fluoride Glasses

    NASA Astrophysics Data System (ADS)

    Bruce, A. J.; Moynihan, C. T.; Loehr, S. R.; Opalka, S. M.; Mossadegh, R.; Perazzo, N. L.; Bansal, N. P.; Doremus, R. H.; Doremus; Drexhage, M. G.

    1985-06-01

    Heavy metal fluoride glasses (HMFG) are potentially useful as optical components in a wide range of devices. Their utilization has so far been delayed mainly because of insufficient material purity and inadequate processing conditions. However, as the result of numerous research efforts, these problems are gradually diminishing, and it now seems likely that the ultimate limitations for use of HMFG components, at least in those applications in which high optical transparency is not a prerequisite, will be imposed by more intrinsic instabilities of the glasses themselves. These include their strong tendency to crystallize on quenching and subsequent reheating, low mechanical and chemical durability, and the possibility that they will undergo significant physical aging in situ. Experimental data relating to these problems have now been obtained, and their relative importance is assessed in this paper.

  15. [Toxic heavy metals in foodstuffs (author's transl)].

    PubMed

    Käferstein, F K

    1980-09-01

    1. In the Federal Republic of Germany two staple foodstuffs, cereals and milk, are regularly checked by means of monitoring programmes for their content of heavy metals, this check being representative for the whole country. Other foodstuffs are analysed in the laboratories of the Food Control Authorities, but these inspections are carried out rather sporadically and are not yet of a "monitoring" nature. 2. The measured values from a number of laboratories are fed into a central data bank (Datenbank-ZEBS) at the Federal Health Office and are thus available for statistical and hygienic evaluation. 3. At present, information is available on the lead, cadmium and mercury content of foodstuffs which represent roughly 70 to 80 per cent of the food consumed by an average adult. The intake of lead, cadmium and mercury due to the consumption of these foodstuffs has been calculated and extrapolated to the complete food consumption. It was found that the value ascertained are clearly lower than the toxicological threshold values published by FAO/WHO. 4. Nevertheless, the intake needs to be limited, because the average heavy metal content of some foodstuffs has increased, probably because of anthropogenic reasons. This is especially likely to apply to the cadmium content of wheat. To attempt a restriction by regulation, is at present not considered in Germany to be the optimal solution. Instead, the Federal Health Office has published guidance values which contain an appeal to the foodstuff industry and food control authorities to investigate the causes, whenever these guidance values are approached or exceeded, with the objective of avoiding high levels. PMID:7456855

  16. Heavy metal retention of different roadside soils

    NASA Astrophysics Data System (ADS)

    Werkenthin, Moritz; Kluge, Björn; Wessolek, Gerd

    2014-05-01

    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.

  17. Heavy Metal Music and Adolescent Suicidality: An Empirical Investigation.

    ERIC Educational Resources Information Center

    Scheel, Karen R.; Westefeld, John S.

    1999-01-01

    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…

  18. Heavy Metal Music and Reckless Behavior among Adolescents.

    ERIC Educational Resources Information Center

    Arnett, Jeffrey

    1991-01-01

    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)

  19. Stabilization of heavy metals in ceramsite made with sewage sludge.

    PubMed

    Xu, G R; Zou, J L; Li, G B

    2008-03-21

    In order to investigate stabilization of heavy metals in ceramsite made with sewage sludge as an additive, the configuration of heavy metals in ceramsite was analysed by XRD and while leaching tests were conducted to find out the effect of sintering temperature (850 degrees C, 900 degrees C, 950 degrees C, 1000 degrees C, 1100 degrees C, and 1200 degrees C), pH (1, 3, 5, 7, 9, and 12), and H2O2 concentration (0.5molL(-1), 1molL(-1), 1.5molL(-1), 3molL(-1), and 5molL(-1)) on stabilization of heavy metals (Cd, Cr, Cu, and Pb) in ceramsite. The results indicate that leaching contents of heavy metals do not change above 1000 degrees C and sintering temperature has a significant effect on stabilization of heavy metals in ceramsite; leaching contents of heavy metals decrease as pH increases and increase as H2O2 concentration increases. XRD analysis reveals that the heavy metals exist in steady forms, mainly Pb2O(CrO(4)), CdSiO3, and CuO at 1100 degrees C. It is therefore concluded that heavy metals are properly stabilized in ceramsite and cannot be easily released into the environment again to cause secondary pollution. PMID:17692459

  20. ENZYME-MEDIATED TRANSFORMATIONS OF HEAVY METALS/METALLOIDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  1. Dietary heavy metal uptake by the least shrew, Cryptotis parva

    SciTech Connect

    Brueske, C.C.; Barrett, G.W. )

    1991-12-01

    Heavy metals from sewage sludge have been reported to concentrate in producers, in primary consumers, and in detritivores. Little research, however, has focused on the uptake of heavy metals from sewage sludge by secondary consumers. The Family Soricidae represents an ideal mammalian taxonomic group to investigate rates of heavy metal transfer between primary and secondary consumers. The least shrew (Cryptotis parva) was used to evaluate the accumulation of heavy metals while maintained on a diet of earthworms collected from long-term sludge-treated old-field communities. This secondary consumer is distributed widely through the eastern United States and its natural diet includes earthworms which makes it a potentially good indicator of heavy metal transfer in areas treated with municipal sludge.

  2. Characterisation of heavy metal discharge into the Ria of Huelva.

    PubMed

    Sainz, A; Grande, J A; de la Torre, M L

    2004-06-01

    The Ria of Huelva estuary, in SW Spain, is known to be one of the most heavy metal contaminated estuaries in the world. River contribution to the estuary of dissolved Cu, Zn, Mn, Cr, Ni, Cd, and As were analysed for the period 1988-2001. The obtained mean values show that this contribution, both because of the magnitude of total metals (895.1 kg/h), composition, toxicity (8.7 kg/h of As+Cd+Pb) and persistence, is an incomparable case in heavy metal contamination of estuaries. The amount and typology of heavy metal discharge to the Ria of Huelva are related to freshwater flow (and, consequently, to rainfall); as a result, two different types of heavy metal discharge can be distinguished in the estuary: during low water (50% of the days), with only 19.3 kg/h of heavy metals, and during high water or flood (17% of the days), where daily maximum discharge of 72,475 kg of heavy metals were recorded, from which 1481 kg were of As, 470 kg of Pb, and 170 kg of Cd. In the most frequent situation (77% of the days), the Odiel River discharges from 90% to 100% of the freshwater received by the estuary. Despite this, the high concentration of heavy metals in the Tinto River water causes this river to discharge into the Ria of Huelva 12.5% of fluvial total dissolved metal load received by the estuary. PMID:15031016

  3. Reducing hazardous heavy metal ions using mangium bark waste.

    PubMed

    Khabibi, Jauhar; Syafii, Wasrin; Sari, Rita Kartika

    2016-08-01

    The objective of this study was to evaluate the characteristics of mangium bark and its biosorbent ability to reduce heavy metal ions in standard solutions and wastewater and to assess changes in bark characteristics after heavy metal absorption. The experiments were conducted to determine heavy metal absorption from solutions of heavy metals alone and in mixtures as well as from wastewater. The results show that mangium bark can absorb heavy metals. Absorption percentages and capacities from single heavy metal solutions showed that Cu(2+) > Ni(2+) > Pb(2+) > Hg(2+), while those from mixture solutions showed that Hg(2+) > Cu(2+) > Pb(2+) > Ni(2+). Wastewater from gold mining only contained Cu, with an absorption percentage and capacity of 42.87 % and 0.75 mg/g, respectively. The highest absorption percentage and capacity of 92.77 % and 5.18 mg/g, respectively, were found for Hg(2+) in a mixture solution and Cu(2+) in single-metal solution. The Cu(2+) absorption process in a single-metal solution changed the biosorbent characteristics of the mangium bark, yielding a decreased crystalline fraction; changed transmittance on hydroxyl, carboxyl, and carbonyl groups; and increased the presence of Cu. In conclusion, mangium bark biosorbent can reduce hazardous heavy metal ions in both standard solutions and wastewater. PMID:27179811

  4. Content of heavy metals in the hair

    NASA Astrophysics Data System (ADS)

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

    2003-05-01

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

  5. Heavy metals in Tuskegee Lake crayfish

    SciTech Connect

    Khan, A.T.

    1995-12-31

    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.

  6. [Beijing common green tree leaves' accumulation capacity for heavy metals].

    PubMed

    Li, Shao-Ning; Kong, Ling-Wei; Lu, Shao-Wei; Chen, Bo; Gao, Chen; Shi, Yuan

    2014-05-01

    Seasonal variation of heavy metal contents in leaves and their relationships with soil heavy metal pollution levels were studied through measuring and analyzing the leaves of the common tree species in Beijing and soil heavy metal contents, to detect heavy metal accumulation ability of plant leaves. The results showed that: (1) the contents of Cu, Pb, Zn in plant leaves first decreased and then increased, again declined with changing the seasons (from spring to winter). Cr concentration showed the trend of first increase and then decrease from spring to winter, and the highest in the autumn; the accumulation capacities of Cu for Babylonica and Japonica were higher in the spring, summer and autumn, while Tabuliformis was in winter; the higher accumulation capacities for Cr, Pb were Japonica and Platycladus, and in winter were Platycladus and Bungeana; the higher accumulation capacities for Zn were Babylonica and Bungeana, while Platycladus in winter; (2) the pollution degree of four kinds of heavy metals (Cu, Cr, Pb, Zn) from downtown to suburbs showed that: Jingshan (C =2.48, C is contamination factor) > Olympic (C = 1.27) > Songshan (C = 1.20) > Shuiguan (C = 1. 18); (3) the heavy metals concentration of same plant leaves in the water of the Great Wall changed larger, but those in the other three areas showed that: Jingshan > Olympic > Songshan; the ability of same species leaf to absorb different sorts of heavy metals showed that: Zn >Cu >Pb >Cr; the difference between Zn content and Cr content was significant (P <0.01); (4) the relationship between heavy metal content in plant leaves and soil heavy metal pollution levels presented a quadratic polynomial relation; the significant correlation was found between other three heavy metal contents of plant samples and soil samples, but they were not the case for the Cu, and the correlation coefficients were above 0. 9. PMID:25055683

  7. Fate and effects of heavy metals on the Arkansas river

    SciTech Connect

    Clements, W.H.

    1991-12-15

    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.

  8. Bismuth film electrodes for heavy metals determination

    NASA Astrophysics Data System (ADS)

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

    2007-05-01

    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 μm in diameter and interelectrode distances of 20 μm 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.

  9. Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems

    PubMed Central

    Singh, Shweta; Siddiqi, Nikhat J.

    2014-01-01

    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

  10. Cell surface engineering of microorganisms towards adsorption of heavy metals.

    PubMed

    Li, Peng-Song; Tao, Hu-Chun

    2015-06-01

    Heavy metal contamination has become a worldwide environmental concern due to its toxicity, non-degradability and food-chain bioaccumulation. Conventional physical and chemical treatment methods for heavy metal removal have disadvantages such as cost-intensiveness, incomplete removal, secondary pollution and the lack of metal specificity. Microbial biomass-based biosorption is one of the approaches gaining increasing attention because it is effective, cheap, and environmental friendly and can work well at low concentrations. To enhance the adsorption properties of microbial cells to heavy metal ions, the cell surface display of various metal-binding proteins/peptides have been performed using a cell surface engineering approach. The surface engineering of Gram-negative bacteria, Gram-positive bacteria and yeast towards the adsorption of heavy metals are reviewed in this article. The problems and future perspectives of this technology are discussed. PMID:23915280

  11. Contamination, toxicity and speciation of heavy metals in an industrialized urban river: Implications for the dispersal of heavy metals.

    PubMed

    Wu, Qihang; Zhou, Haichao; Tam, Nora F Y; Tian, Yu; Tan, Yang; Zhou, Song; Li, Qing; Chen, Yongheng; Leung, Jonathan Y S

    2016-03-15

    Urban rivers are often utilized by the local residents as water source, but they can be polluted by heavy metals due to industrialization. Here, the concentrations, toxicity, speciation and vertical profiles of heavy metals in sediment were examined to evaluate their impact, dispersal and temporal variation in Dongbao River. Results showed that the sediment in the industrialized areas was seriously contaminated with Cr, Cu and Ni which posed acute toxicity. Heavy metals, except Cr and Pb, were mainly associated with non-residual fractions, indicating their high mobility and bioavailability. The non-industrialized areas were also seriously contaminated, suggesting the dispersal of heavy metals along the river. The surface sediment could be more contaminated than the deep sediment, indicating the recent pollution events. Overall, when the point sources are not properly regulated, intense industrialization can cause both serious contamination and dispersal of heavy metals, which have far-reaching consequences in public health and environment. PMID:26856647

  12. [Application of ICP-MS to determination of heavy metal content of heavy metals in two kinds of N fertilizer].

    PubMed

    Rui, Yu-kui; Shen, Jian-bo; Zhang, Fu-suo

    2008-10-01

    Environmental safety has been the focus worldwide, where involved are the pollutions of heavy metals, pesticides and persistent organic pollutants. Fertilizer has become one of the polluting sources of heavy metals, which are very deleterious to human health and environmental safety. Heavy metals are difficult to metabolize in human body and very harmful, so research on the pollution of heavy metals is considered increasingly important. The pollution sources of heavy metals include waste residue, waste water and exhaust gas from industry and automobile, and garbage from human life. The heavy metals in fertilizer can endanger the human body by the crop containing heavy metals. Two kinds of nitrogen fertilizer were analyzed in terms of the content of heavy metals by ICP-MS, and the results showed that the content of 10 kinds of heavy metals (Al, Ti, Cr, Ni, Cu, Zn, As, Cd, Hg and Pb) in (NH4)2SO4 was 1345.13, 35.12, 2539.27, 287.26, 674.05, 270.79, 42.54, 22.13, 27.20 and 123.87 ng x g(-1) respectively; and in CO(NH2)2 it is 71.59, 5.36, 1167.71, 188.60, 7.46, 64.45, 10.55, 0.00, 0.09 and 3.71 ng x g(-1) respectively. All the data showed that CO(NH2)2 contained much less heavy metals than (NH4)2SO4, so we should select CO(NH2)2 as the nitrogen fertilizer in agricultural production. PMID:19123422

  13. Heavy metal displacement in chelate-irrigated soil during phytoremediation

    NASA Astrophysics Data System (ADS)

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

    2003-03-01

    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.

  14. Toxicity of heavy metals and metal-containing nanoparticles on plants.

    PubMed

    Mustafa, Ghazala; Komatsu, Setsuko

    2016-08-01

    Plants are under the continual threat of changing climatic conditions that are associated with various types of abiotic stresses. In particular, heavy metal contamination is a major environmental concern that restricts plant growth. Plants absorb heavy metals along with essential elements from the soil and have evolved different strategies to cope with the accumulation of heavy metals. The use of proteomic techniques is an effective approach to investigate and identify the biological mechanisms and pathways affected by heavy metals and metal-containing nanoparticles. The present review focuses on recent advances and summarizes the results from proteomic studies aimed at understanding the response mechanisms of plants under heavy metal and metal-containing nanoparticle stress. Transport of heavy metal ions is regulated through the cell wall and plasma membrane and then sequestered in the vacuole. In addition, the role of different metal chelators involved in the detoxification and sequestration of heavy metals is critically reviewed, and changes in protein profiles of plants exposed to metal-containing nanoparticles are discussed in detail. Finally, strategies for gaining new insights into plant tolerance mechanisms to heavy metal and metal-containing nanoparticle stress are presented. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock. PMID:26940747

  15. Leaching Properties of Naturally Occurring Heavy Metals from Soils

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Hoshino, M.; Yoshikawa, M.; Hara, J.; Sugita, H.

    2014-12-01

    The major threats to human health from heavy metals are associated with exposure to arsenic, lead, cadmium, chromium, mercury, as well as some other elements. The effects of such heavy metals on human health have been extensively studied and reviewed by international organizations such as WHO. Due to their toxicity, heavy metal contaminations have been regulated by national environmental standards in many countries, and/or laws such as the Soil Contamination Countermeasures Act in Japan. Leaching of naturally occurring heavy metals from the soils, especially those around abandoned metal mines into surrounding water systems, either groundwater or surface water systems, is one of the major pathways of exposure. Therefore, understanding the leaching properties of toxic heavy metals from naturally polluted soils is of fundamentally importance for effectively managing abandoned metal mines, excavated rocks discharged from infrastructure constructions such as tunneling, and/or selecting a pertinent countermeasure against pollution when it is necessary. In this study, soil samples taken from the surroundings of abandoned metal mines in different regions in Japan were collected and analyzed. The samples contained multiple heavy metals such as lead, arsenic and chromium. Standard leaching test and sequential leaching test considering different forms of contaminants, such as trivalent and pentavalent arsenics, and trivalent and hexavalent chromiums, together with standard test for evaluating total concentration, X-ray Fluorescence Analysis (XRF), X-ray diffraction analysis (XRD) and Cation Exchange Capacity (CEC) tests were performed. In addition, sequential leaching tests were performed to evaluate long-term leaching properties of lead from representative samples. This presentation introduces the details of the above experimental study, discusses the relationships among leaching properties and chemical and mineral compositions, indicates the difficulties associated with

  16. Accumulation of heavy metals in selected medicinal plants.

    PubMed

    Sarma, Hemen; Deka, Suresh; Deka, Hemen; Saikia, Rashmi Rekha

    2011-01-01

    In this review, we evaluate the reports published between 1993 and 2011 that address the heavy metal accumulation in 88 medicinal plant species. We compare the safe limits for heavy metals set by governmental agencies vs. the levels at which such metals actually exist in selected medicinal plants. We also evaluate the uses and effectiveness of medicinal plants in health care, and assess the hazards of medicinal plant uses, in view of the growing worldwide use of medicinal plants. From our extensive review of the literature, we discovered that a maximum permissible level (MPL) of Pb is exceeded in 21 plant medicine species, Cd in 44 species, and Hg in 10 species. Vetiveria zizanioides a potential candidate species for the treatment of cardiovascular diseases absorb a wide range of heavy metals from metal-contaminated soils. We believe that this species is the single most impressive example of a potentially hazardous medicinal plant. Based on our review, we endorse the hypothesis that heavy metal accumulation by medicinal plants is mainly caused by extraction of soluble metals from contaminated soil, sediments and air. One continuing problem in protecting consumers of plant-based medicines is that permissible levels of all heavy metals in herbal medicine have not yet been standardized by regulating governmental entities. Moreover, there are few limit tests that exist for heavy metal content of medicinal plants, or permissible limits for essential dietary minerals, in most medicinal plants. The dearth of such limits hamstrings development of medicinal plant research and delays the release of either new or improved versions of medicinal plants or their components. In the present review, we emphasize that medicinal plants are often subjected to heavy metal contamination and that the levels at which these heavy metals sometimes occur exceeds permissible levels for some species. Therefore, collecting medicinal plants from areas that are, or may be, contaminated should be

  17. Modeling the transport of heavy metals in soils. Monograph report

    SciTech Connect

    Selim, H.M.; Amacher, M.C.; Iskandar, I.K.

    1990-09-01

    Retention reactions in soils are important processes that govern the fate of chemical contaminants such as heavy metals in groundwaters. The ability to predict the mobility of heavy metals in the soil and the potential contamination of groundwater supplies is a prerequisite in any program aimed at protecting groundwater quality. Mathematical models that describe the potential mobility of heavy metals must include description of the retention processes in the soil matrix. Extensive research has been carried out to describe the retention-release behavior of several heavy metals in soils. Fuller, Alesii et al., Dowdy and Volk, Ellis et al., and Kabata-Pendias and Pendias, among others, have presented overviews of retention-release and leaching investigations for several heavy metals in soils. The publications also describe soil physical and chemical properties that influence the fate of heavy metals in the soil environment and their potential leaching to groundwater supplies. Over the last two decades, however, only a limited number of investigations have attempted to quantify the heavy metals in laboratory soil columns or in soil profiles under field conditions have only recently appeared in the literature.

  18. Improving crop tolerance to heavy metal stress by polyamine application.

    PubMed

    Soudek, Petr; Ursu, Marina; Petrová, Šárka; Vaněk, Tomáš

    2016-12-15

    Many areas have been heavily contaminated by heavy metals from industry and are not suitable for food production. The consumption of contaminated foods represents a health risk in humans, although some heavy metals are essential at low concentrations. Increasing the concentrations of essential elements in foods is one goal to improve nutrition. The aim of this study was to increase the accumulation of heavy metals in plant foods by the external application of putrescine. The levels of cadmium, zinc and iron were measured in different vegetables grown in hydroponic medium supplemented with heavy metals and compared with those grown in a reference medium. The estimated daily intake, based on the average daily consumption for various vegetable types, and the influence of polyamines on metal uptake were calculated. PMID:27451175

  19. Heavy metals influence on ascorbic acid level

    NASA Astrophysics Data System (ADS)

    Kamaldinov, E. V.; Patrashkov, S. A.; Batenyeva, E. V.; Korotkevich, O. S.

    2003-05-01

    It is well known that heavy metals (HM) are extremely dangerous pollutants influencing to metabolism in animals' organisms. The vitamin C is one of the most important metabolites taking part in many biochemical processes. We studied the influence of main essential HM-Zn and Cu as well as the based supertoxical elements - Cd and Pd on ascorbic acid level in serum. The studies were carried out in Tulinskoe farm of Novosibirsk region. The objects of investigations were piglets (2 month after weaning) and 6-month pigs of Early Ripe Meat breed. The levels of HM in bristle were found by stripping voltammetric analysis using the TA-2 analyzer. Vitamin C content was determined by I.P. Kondrakhin (1985) method using 2,2-dipyridyl. The significant negative correlations between Pb, Cd content and vitamin C (-0.46 ± 0.18, -0.47 ± 0.19) in 6-month pigs were determined. The tendencies of negative correlation between all HM levels in hair and ascorbic acid level in plasma of piglets were revealed. Thus, the obtained correlations let us to suppose that all studied HM influence on 1-gulono-gamma-lactone oxidase and other vitamin C metabolism enzymes activity.

  20. Adsorption behavior of heavy metals on biomaterials.

    PubMed

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

    2004-09-01

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

  1. pfmdr2 confers heavy metal resistance to Plasmodium falciparum.

    PubMed

    Rosenberg, Elli; Litus, Ilena; Schwarzfuchs, Nurit; Sinay, Rosa; Schlesinger, Pnina; Golenser, Jacob; Baumeister, Stefan; Lingelbach, Klaus; Pollack, Yaakov

    2006-09-15

    Heavy metals are required by all organisms for normal function, but high levels of heavy metals are toxic. Therefore, homeostasis of these metals is crucial. In the human malaria-causing agent Plasmodium falciparum, the mechanisms of heavy metal transport have yet to be characterized. We have developed a P. falciparum line resistant to heavy metals from a wild-type line sensitive to heavy metals. A molecular and biochemical analysis of the involvement of the P. falciparum multidrug resistance 2 (pfmdr2) gene, an ABC-type transporter, in heavy metal homeostasis was studied. Using a novel uptake assay applied on these two strains, it was demonstrated that, when exposed to heavy metals, the sensitive line accumulates metal, whereas no accumulation was observed in the resistant line. The accumulation occurs within the parasite itself and not in the cytoplasm of the red blood cell. This difference in the accumulation pattern is not a result of amplification of the pfmdr2 gene or of a change in the expression pattern of the gene in the two lines. Sequencing of the gene from both lines revealed a major difference; a stop codon is found in the sensitive line upstream of the normal termination, resulting in a truncated protein that lacks 188 amino acids that contain a portion of the essential cytoplasmatic transporter domain, thereby rendering it inactive. In contrast, the resistant line harbors a full-length, active protein. These findings strongly suggest that the PFMDR2 protein acts as an efflux pump of heavy metals. PMID:16849328

  2. Heavy Metals in Marine Pollution Perspective-A Mini Review

    NASA Astrophysics Data System (ADS)

    Ansari, T. M.; Marr, I. L.; Tariq, N.

    Anthropogenic inputs of pollutants such as heavy metals into the marine environment have increased their levels to large extents within past a few decades. These pollutants tend to accumulate in the bottom sediments. As a result, ecosystems such as seaports or other industrialized coastal areas that have chronic inputs of metals have highly contaminated sediments. This characteristic has led to concerns over the ecological effects that may be associated with sediment quality. Of particular concern are toxic effects and the potential for bioaccumulation of metals in biota exposed to the sediments. The availability of heavy metals to the biomass of a polluted region is the prime concern both in terms of the prediction of the effects of metal pollution on an ecosystem and in terms of possible human health risks. With growing interest on environmental issues, several intriguing questions related to heavy metals are often raised. This review addresses the basic concepts, sources, speciation, mode of action, levels, analytical measurement, bioavailability, bioaccumulation, biological role and toxicity of heavy metals in the marine environment. Lead, Cadmium, Zinc, Copper, Manganese, Iron, Mercury, Arsenic and Barium are selected because these metals are common and are often at measurable levels in marine samples. An attempt has been made to answer the queries presented by the environmentalists working on various aspects of heavy metal pollution in the marine environment

  3. Heavy metals in livers and kidneys of goats in Alabama

    SciTech Connect

    Khan, A.T.; Diffay, B.C.; Datiri, B.C.

    1995-10-01

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

  4. Heavy Metals and Epigenetic Alterations in Brain Tumors

    PubMed Central

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

    2014-01-01

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

  5. Heavy-metal complexation by de novo peptide design.

    PubMed

    Farrer, Brian T; Pecoraro, Vincent L

    2002-11-01

    From poisoning caused by lead-based paint on domestic buildings to groundwater contamination by naturally occurring arsenic deposits in India, heavy-metal toxicity is a global health problem. Contaminated ground water and acute cases of heavy-metal poisoning are treated with chelators to remove the heavy metals from the contaminated site or person. This review discusses the effort to generate heavy-metal chelators through peptide de novo design. De novo design entails the design of a primary sequence that will precisely fold into a predetermined secondary and tertiary protein structure. The first-generation peptide chelator used to initiate this investigation is the three-stranded coild coil containing Cys. Cys provides a potential trigonal binding site with soft thiolate ligands, which has been proposed to provide specific interactions with heavy metals. This hypothesis derives from the observation that similar sites on natural proteins show selectivity for heavy metals over other essential metals, such as Zn or Mg. A description of two systems, the TRI series and the IZ-AC peptide, is given, highlighting the interaction of these peptides with Hg, Cd, As and Pb. Arguments are also presented for the potential use of three-helix bundles as a second-generation design. PMID:12478724

  6. Heavy metals content of municipal wastewater and sludges in Kuwait.

    PubMed

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

    2004-01-01

    Municipal wastewater may contain heavy metals, which are hazardous to the environment and humans. With stringent regulations concerning water reuse and sludge utilization in agriculture, there is a great need to determine levels of heavy metals in liquid wastes, sludges and agricultural crops. The state of Kuwait has programs to utilize waste sludge produced at wastewater treatment plants as soil conditioner and fertilizer for greenery and agricultural development projects and to reuse treated wastewater effluents in irrigation. The common metals found in Kuwait's raw wastewater and sludge are Cd, Cr, Cu, Hg, Ni, Pb, and Zn. The effects of accumulation of heavy metals in soil are long lasting and even permanent. In this study, the variations in the concentration levels of heavy metals were measured in wastewater and sludge produced at Ardiya municipal wastewater treatment plant in Kuwait. A relationship was observed between the concentrations of heavy metals in treated wastewater and sludge used for agriculture and the level of accumulated heavy metals found in residual tissues of some crops. PMID:15027823

  7. Heavy metals and epigenetic alterations in brain tumors.

    PubMed

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

    2014-12-01

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

  8. NMR microscopy of heavy metal absorption in calcium alginate beads

    SciTech Connect

    Nestle, N.; Kimmich, R.

    1996-01-01

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

  9. DETERMINATION OF HEAVY METALS AND PESTICIDES IN GINSENG PRODUCTS

    EPA Science Inventory

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

  10. Detection of heavy metal by paper-based microfluidics.

    PubMed

    Lin, Yang; Gritsenko, Dmitry; Feng, Shaolong; Teh, Yi Chen; Lu, Xiaonan; Xu, Jie

    2016-09-15

    Heavy metal pollution has shown great threat to the environment and public health worldwide. Current methods for the detection of heavy metals require expensive instrumentation and laborious operation, which can only be accomplished in centralized laboratories. Various microfluidic paper-based analytical devices have been developed recently as simple, cheap and disposable alternatives to conventional ones for on-site detection of heavy metals. In this review, we first summarize current development of paper-based analytical devices and discuss the selection of paper substrates, methods of device fabrication, and relevant theories in these devices. We then compare and categorize recent reports on detection of heavy metals using paper-based microfluidic devices on the basis of various detection mechanisms, such as colorimetric, fluorescent, and electrochemical methods. To finalize, the future development and trend in this field are discussed. PMID:27131999

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

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

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

  12. Combined toxicity of heavy metal mixtures in liver cells.

    PubMed

    Lin, Xialu; Gu, Yuanliang; Zhou, Qi; Mao, Guochuan; Zou, Baobo; Zhao, Jinshun

    2016-09-01

    With rapid industrialization, China is now facing great challenges in heavy metal contamination in the environment. Human exposure to heavy metals through air, water and food commonly involves a mixture consisting of multiple heavy metals. In this study, eight common heavy metals (Pb, Cd, Hg, Cu, Zn, Mn, Cr, Ni) that cause environmental contamination were selected to investigate the combined toxicity of different heavy metal mixtures in HL7702 cells. Toxicity (24 h LC50 ) of each individual metal on the cells ranked Hg > Cr = Cd > Cu > Zn > Ni > Mn > Pb; toxicity of the different mixtures ranked: M5 > M3PbHgCd > M5+Mn > M5+Cu > M2CdNi > M4A > M8-Mn > M8 > M5+Zn > M4B > M8-Cr > M8-Zn > M8-Cu > M8-Pb > M8-Cd > M8-Hg > M8-Ni > M3PbHgNi > M3CuZnMn. The cytotoxicity data of individual metals were successfully used to build the additive models of two- to eight-component metal mixtures. The comparison between additive model and combination model or partly additive model was useful to evaluate the combined effects in mixture. Synergistic, antagonistic or additive effects of the toxicity were observed in different mixtures. These results suggest that the combined effects should be considered in the risk assessment of heavy metal co-exposure, and more comprehensive investigations on the combined effects of different heavy metal mixtures are needed in the future. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26865462

  13. Heavy metal removal using peat/wetland treatment

    SciTech Connect

    Murawski, S.

    1994-12-31

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

  14. Variation in dry grassland communities along a heavy metals gradient.

    PubMed

    Woch, Marcin W; Kapusta, Paweł; Stefanowicz, Anna M

    2016-01-01

    The aim of this study was to investigate the variation in plant communities growing on metal-enriched sites created by historical Zn–Pb mining. The study sites were 65 small heaps of waste rock covered by grassland vegetation and scattered mostly over agricultural land of southern Poland. The sites were described in terms of plant coverage, species richness and composition, and the composition of plant traits. They were classified using phytosociological methods and detrended correspondence analysis. Identified plant communities were compared for vegetation parameters and habitat properties (soil characteristics, distance from the forest) by analysis of variance. The variation in plant community parameters was explained by multiple regression, in which the predictors were properties of the habitat selected on the basis of factor analysis. Grasslands that developed at low and high concentrations of heavy metals in soil were similar to some extent: they were composed on average of 17–20 species (per 4 m(2)), and their total coverage exceeded 90%. The species composition changed substantially with increasing contamination with heavy metals; metal-sensitive species withdrew, while the metal-tolerant became more abundant. Other important predictors of community structure were: proximity to the forest (responsible for the encroachment of competitive forest species and ruderals), and the thickness of the surface soil (shallow soil favored the formation of the heavy metal grassland). The heavy metal grassland was closely related to the dry calcareous grasslands. The former was an earlier succession stage of the latter at low contamination with heavy metals. PMID:26493699

  15. Successful treatment of potentially fatal heavy metal poisonings.

    PubMed

    Wang, Ernest E; Mahajan, Niraj; Wills, Brandon; Leikin, Jerrold

    2007-04-01

    Pure inorganic heavy metal ingestions for suicidal intent are a rare occurrence. Most case reports on this subject focus on the serious neurological, hepatic, or renal side effects. We describe two cases of significant heavy metal poisonings (arsenic trioxide and mercuric chloride) that were successfully managed with aggressive decontamination and combined chelation therapy. Both chemicals were obtained in pure powder form through the Internet. PMID:17394994

  16. Human health risk assessment of heavy metals in urban stormwater.

    PubMed

    Ma, Yukun; Egodawatta, Prasanna; McGree, James; Liu, An; Goonetilleke, Ashantha

    2016-07-01

    Toxic chemical pollutants such as heavy metals (HMs) are commonly present in urban stormwater. These pollutants can pose a significant risk to human health and hence a significant barrier for urban stormwater reuse. The primary aim of this study was to develop an approach for quantitatively assessing the risk to human health due to the presence of HMs in stormwater. This approach will lead to informed decision making in relation to risk management of urban stormwater reuse, enabling efficient implementation of appropriate treatment strategies. In this study, risks to human health from heavy metals were assessed as hazard index (HI) and quantified as a function of traffic and land use related parameters. Traffic and land use are the primary factors influencing heavy metal loads in the urban environment. The risks posed by heavy metals associated with total solids and fine solids (<150μm) were considered to represent the maximum and minimum risk levels, respectively. The study outcomes confirmed that Cr, Mn and Pb pose the highest risks, although these elements are generally present in low concentrations. The study also found that even though the presence of a single heavy metal does not pose a significant risk, the presence of multiple heavy metals could be detrimental to human health. These findings suggest that stormwater guidelines should consider the combined risk from multiple heavy metals rather than the threshold concentration of an individual species. Furthermore, it was found that risk to human health from heavy metals in stormwater is significantly influenced by traffic volume and the risk associated with stormwater from industrial areas is generally higher than that from commercial and residential areas. PMID:27046140

  17. Distribution of heavy metals from flue gas in algal bioreactor

    NASA Astrophysics Data System (ADS)

    Napan, Katerine

    Flue gas from coal-fired power plants is a major source of CO2 to the atmosphere. Microalgae can use this enriched form of CO2 as carbon source and in turn the biomass can be used to produce food, feed, fertilizer and biofuels. However, along with CO2, coal-based flue gas will inevitably introduce heavy metals, which have a high affinity to bind algal cells, could be toxic to the organisms and if transferred to the products could limit their uses. This study seeks to address the distribution and impact of heavy metals present in flue gas on microalgae production systems. To comprehend its effects, algae Scenedesmus obliquus was grown in batch reactors in a multimetal system. Ten heavy metals (Cu, Co, Zn, Pb, As, Se, Cr, Hg, Ni and Cd) were selected and were evaluated at four concentrations (1X, 2X, 5X and 10X). Results show that most heavy metals accumulated mainly in biomass and were found in very low concentrations in media. Hg was shown to be lost from the culture, with low amounts present in the biomass. An upper limit for As uptake was observed, suggesting its likelihood to build-up in the system during medium recycle. The As limited bioaccumulation was overcome by addition of sulfur to the algal medium. Heavy metal at 2X, 5X and 10X inhibited both growth and lipid production, while at the reference concentration both biomass and lipids yields were increased. Heavy metal concentrations in the medium and biomass were time dependent, and at the end of the cultivation most heavy metals in the supernatant solution complied with the recommendations for irrigation water, while biomass was below limits for cattle and poultry feed, fertilizer, plastic and paper. This research shows that bioremediation of CO2 and heavy metals in combination with energy production can be integrated, which is an environmentally friendly form of biotechnology.

  18. An optical dosimeter for monitoring heavy metal ions in water

    NASA Astrophysics Data System (ADS)

    Mignani, Anna G.; Regan, Fiona; Leamy, D.; Mencaglia, A. A.; Ciaccheri, L.

    2005-05-01

    This work presents an optochemical dosimeter for determining and discriminating nickel, copper, and cobalt ions in water that can be used as an early warning system for water pollution. An inexpensive fiber optic spectrophotometer monitors the sensor's spectral behavior under exposure to water solutions of heavy metal ions in the 1-10 mg/l concentration range. The Principal Component Analysis (PCA) method quantitatively determines the heavy metals and discriminates their type and combination.

  19. Comparison of Eleven Heavy Metals in Moringa Oleifera Lam. Products.

    PubMed

    Limmatvapirat, C; Limmatvapirat, S; Charoenteeraboon, J; Wessapan, C; Kumsum, A; Jenwithayaamornwech, S; Luangthuwapranit, P

    2015-01-01

    Eleven heavy metals in various products of Moringa oleifera were analyzed to determine eleven heavy metals (Al, As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, and Zn) using Inductively Coupled Plasma-Mass Spectrometry. The products of M. oleifera were purchased in Nakhon Pathom, Thailand. All products were digested with nitric acid solution before determining the concentrations of heavy metals. The recoveries of all heavy metals were found to be in the range of 99.89-103.05%. Several criteria such as linearity, limits of detection, limits of quantification, specificity, precision under repeatability conditions and intermediate precision reproducibility were evaluated. Results indicate that this method could be used in the laboratory for determination of eleven heavy metals in M. oleifera products with acceptable analytical performance. The results of analysis showed that the highest concentrations of As, Cr, Hg, and Mn were found in tea leaves while the highest concentrations of Al, Cd, Cu, Fe, Ni, Pb, and Zn were found in leaf capsules. Continuous monitoring of heavy metals in M. oleifera products is crucial for consumer health. PMID:26664066

  20. Removal and recovery of heavy metals from incinerator ash residues

    SciTech Connect

    Forrester, K.E.

    1997-12-01

    This paper presents results of a novel and state-of-the-art patent-pending processes developed jointly by Forrester Environmental Services Inc. (FESI) and Brookhaven National Laboratories (BNL) for the extraction and recovery of lead (Pb), Cadmium (Cd), Copper (Cu), Zinc (Zn) and other heavy metals from heavy metal bearing wastes including but not limited to solid waste incinerator bottom ash, flyash and combined ash. The heavy metal extraction and recovery processes were found to be capable of high percentage of heavy metals extraction and recovery at a relatively low cost under bench scale and full-scale refuse incinerator facility conditions. This paper presents empirical data from bench scale studies only, as the full-scale data is currently under review. The ash product remaining after extraction passed all TCLP regulatory limits and retained only minimal Pb, Cd, Cu, and Zn content and other water insoluble heavy metal compounds. Results of heavy metals recovery and low cost from ongoing field applications of this technology are consistent with the bench scale data presented within this paper.

  1. Comparison of Eleven Heavy Metals in Moringa Oleifera Lam. Products

    PubMed Central

    Limmatvapirat, C.; Limmatvapirat, S.; Charoenteeraboon, J.; Wessapan, C.; Kumsum, A.; Jenwithayaamornwech, S.; Luangthuwapranit, P.

    2015-01-01

    Eleven heavy metals in various products of Moringa oleifera were analyzed to determine eleven heavy metals (Al, As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, and Zn) using Inductively Coupled Plasma-Mass Spectrometry. The products of M. oleifera were purchased in Nakhon Pathom, Thailand. All products were digested with nitric acid solution before determining the concentrations of heavy metals. The recoveries of all heavy metals were found to be in the range of 99.89-103.05%. Several criteria such as linearity, limits of detection, limits of quantification, specificity, precision under repeatability conditions and intermediate precision reproducibility were evaluated. Results indicate that this method could be used in the laboratory for determination of eleven heavy metals in M. oleifera products with acceptable analytical performance. The results of analysis showed that the highest concentrations of As, Cr, Hg, and Mn were found in tea leaves while the highest concentrations of Al, Cd, Cu, Fe, Ni, Pb, and Zn were found in leaf capsules. Continuous monitoring of heavy metals in M. oleifera products is crucial for consumer health. PMID:26664066

  2. Soil reclamation by municipal sewage compost: Heavy metals migration study.

    PubMed

    Kowalkowski, Tomasz; Buszewski, Bogusław

    2009-04-01

    This paper describes sorption and transport phenomena of selected heavy metals (e.g., Pb, Zn, Ni and Cu) in the superficial layer of soil and sewage sludge compost. The main aim of the study was the investigation of possibility of heavy metals contamination in soil profile reclaimed by sewage sludge compost. The column leaching test as well as the sequential Tessier extraction procedure were applied to investigate the mitigation of heavy metals. The results revealed that distribution of metals in specific Tessier fractions was the major factor influencing their transport in the investigated soils profiles. Moreover, sorption capacity of the soil sample studied was substantially greater to prevent transportation of metals into the lower horizons and groundwater. PMID:19241267

  3. Effect of ultrasonic treatment on heavy metal decontamination in milk.

    PubMed

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

    2014-11-01

    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

  4. Electrokinetic treatment of an agricultural soil contaminated with heavy metals.

    PubMed

    Figueroa, Arylein; Cameselle, Claudio; Gouveia, Susana; Hansen, Henrik K

    2016-07-28

    The high organic matter content in agricultural soils tends to complex and retain contaminants such as heavy metals. Electrokinetic remediation was tested in an agricultural soil contaminated with Co(+2), Zn(+2), Cd(+2), Cu(+2), Cr(VI), Pb(+2) and Hg(+2). The unenhanced electrokinetic treatment was not able to remove heavy metals from the soil due to the formation of precipitates in the alkaline environment in the soil section close to the cathode. Moreover, the interaction between metals and organic matter probably limited metal transportation under the effect of the electric field. Citric acid and ethylenediaminetetraacetic acid (EDTA) were used in the catholyte as complexing agents in order to enhance the extractability and removal of heavy metals from soil. These complexing agents formed negatively charged complexes that migrated towards the anode. The acid front electrogenerated at the anode favored the dissolution of heavy metals that were transported towards the cathode. The combined effect of the soil pH and the complexing agents resulted in the accumulation of heavy metals in the center of the soil specimen. PMID:27127923

  5. Removal of Trichloroethylene and Heavy Metals by Zerovalent Iron Nanoparticles

    NASA Astrophysics Data System (ADS)

    Boparai, H. K.; O'Carroll, D. M.

    2009-05-01

    Heavy metals combined with chlorinated solvents are one class of mixed waste found at various hazardous waste sites in North America. Nano zerovalent iron (nZVI), an emerging technology, is being successfully used for treating chlorinated solvents and heavy metals independently, however comparatively little research has investigated the remediation of the wastes when they are present in the same mixture. The remediation of trichloroethylene (TCE)/heavy metal waste mixtures via nZVI has been investigated in the present study. Results suggest that some metals are reduced by nZVI to their zerovalent state and thus precipitate on nZVI particles. This improves the contaminant removal performance of nZVI by forming bimetallic iron nanoparticles. Other metals are directly precipitated or adsorbed on the nZVI particles in their original oxidation state and are rendered immobile. In some cases the presence of the heavy metals in the waste mixture enhanced the dechlorination of TCE while in other cases it did not. This study suggests that nano zerovalent iron particles can be effectively used for the remediation of mixed contamination of heavy metals and chlorinated solvents. Results have been supported by a variety of techniques including X-ray photoelectron spectroscopy (XPS) analysis.

  6. Body burdens of heavy metals in Lake Michigan wetland turtles.

    PubMed

    Smith, Dayna L; Cooper, Matthew J; Kosiara, Jessica M; Lamberti, Gary A

    2016-02-01

    Tissue heavy metal concentrations in painted (Chrysemys picta) and snapping (Chelydra serpentina) turtles from Lake Michigan coastal wetlands were analyzed to determine (1) whether turtles accumulated heavy metals, (2) if tissue metal concentrations were related to environmental metal concentrations, and (3) the potential for non-lethal sampling techniques to be used for monitoring heavy metal body burdens in freshwater turtles. Muscle, liver, shell, and claw samples were collected from painted and snapping turtles and analyzed for cadmium, chromium, copper, iron, lead, magnesium, manganese, and zinc. Turtle tissues had measurable quantities of all eight metals analyzed. Statistically significant correlations between tissue metal concentrations and sediment metal concentrations were found for a subset of metals. Metals were generally found in higher concentrations in the larger snapping turtles than in painted turtles. In addition, non-lethal samples of shell and claw were found to be possible alternatives to lethal liver and muscle samples for some metals. Human consumption of snapping turtles presents potential health risks if turtles are harvested from contaminated areas. Overall, our results suggest that turtles could be a valuable component of contaminant monitoring programs for wetland ecosystems. PMID:26832725

  7. 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...

  8. Biomonitoring heavy metal contaminations by moss visible parameters.

    PubMed

    Chen, Yang-Er; Cui, Jun-Mei; Yang, Jin-Chuan; Zhang, Zhong-Wei; Yuan, Ming; Song, Chun; Yang, Hui; Liu, Han-Mei; Wang, Chang-Quan; Zhang, Huai-Yu; Zeng, Xian-Yin; Yuan, Shu

    2015-10-15

    Traditional sampling for heavy metal monitoring is a time-consuming and inconvenient method, which also does not indicate contaminants non-invasively and instantaneously. Moss is sensitive to heavy metals and is therefore considered a pollution indicator. However, it is unknown what kind physiological parameters can indicate metal contaminations quickly and non-invasively. Here, we systematically examined the effects of six heavy metals on physiological parameters and photosynthetic activities of two moss species grown in aquatic media or moist soil surface. We suggest that a phenotype with anthocyanin accumulation pattern and chlorosis pattern and two chlorophyll fluorescence parameters with their images can roughly reflect metal species groups, concentrations and differences between the two moss species. In other words, metal contaminations could be roughly estimated visually using the naked eye. Enzymatic and non-enzymatic anti-oxidative abilities and photosynthetic protein contents of Eurhynchium eustegium were higher than those of Taxiphyllum taxirameum, indicating their differential metal tolerance. Neither anti-oxidative abilities nor photosynthetic proteins were found to be ideal indicators. This study provides new ideas to monitor heavy metals rapidly and non-invasively in water or on wetland and moist soil surface. PMID:25919648

  9. SOIL MICROBIAL EFFECTS ON HEAVY METAL UPTAKE INTO HYPERACCUMULATORS

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  10. Heavy Metals Contamination of Table Salt Consumed in Iran

    PubMed Central

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

    2010-01-01

    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 μg/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

  11. Magnetic process for removing heavy metals from water employing magnetites

    DOEpatents

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

    2003-07-22

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

  12. Magnetic process for removing heavy metals from water employing magnetites

    DOEpatents

    Prenger, F. Coyne; Hill, Dallas D.

    2006-12-26

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

  13. Phytochemicals Mediated Remediation of Neurotoxicity Induced by Heavy Metals.

    PubMed

    Gupta, Vivek Kumar; Singh, Shweta; Agrawal, Anju; Siddiqi, Nikhat Jamal; Sharma, Bechan

    2015-01-01

    Almost all the environmental components including both the abiotic and biotic factors have been consistently threatened by excessive contamination of heavy metals continuously released from various sources. Different heavy metals have been reported to generate adverse effects in many ways. Heavy metals induced neurotoxicity and impairment in signalling cascade leading to cell death (apoptosis) has been indicated by several workers. On one hand, these metals are required by the cellular systems to regulate various biological functions of normal cells, while on the other their biomagnification in the cellular systems produces adverse effects. The mechanism by which the heavy metals induce neurotoxicity follows free radicals production pathway(s) specially the generation of reactive oxygen species and reactive nitrogen species. These free radicals produced in excess have been shown to create an imbalance between the oxidative and antioxidative systems leading to emergence of oxidative stress, which may cause necrosis, DNA damage, and many neurodegenerative disorders. This mini review summarizes the current knowledge available on the protective role of varied natural products isolated from different herbs/plants in imparting protection against heavy metals (cadmium, lead, arsenic, and mercury) mediated neurotoxicity. PMID:26618004

  14. Phytochemicals Mediated Remediation of Neurotoxicity Induced by Heavy Metals

    PubMed Central

    Gupta, Vivek Kumar; Singh, Shweta; Agrawal, Anju; Siddiqi, Nikhat Jamal; Sharma, Bechan

    2015-01-01

    Almost all the environmental components including both the abiotic and biotic factors have been consistently threatened by excessive contamination of heavy metals continuously released from various sources. Different heavy metals have been reported to generate adverse effects in many ways. Heavy metals induced neurotoxicity and impairment in signalling cascade leading to cell death (apoptosis) has been indicated by several workers. On one hand, these metals are required by the cellular systems to regulate various biological functions of normal cells, while on the other their biomagnification in the cellular systems produces adverse effects. The mechanism by which the heavy metals induce neurotoxicity follows free radicals production pathway(s) specially the generation of reactive oxygen species and reactive nitrogen species. These free radicals produced in excess have been shown to create an imbalance between the oxidative and antioxidative systems leading to emergence of oxidative stress, which may cause necrosis, DNA damage, and many neurodegenerative disorders. This mini review summarizes the current knowledge available on the protective role of varied natural products isolated from different herbs/plants in imparting protection against heavy metals (cadmium, lead, arsenic, and mercury) mediated neurotoxicity. PMID:26618004

  15. Study of heavy metals in some environmental samples.

    PubMed

    Ahmad, Imtiaz; Rashid, Haroon; Rehman, Zia Ur

    2009-11-01

    Fuels like coal and rubber are frequently used for brick burning. However, both coal and rubber contain heavy metals. These heavy metals may elutriate in the wake of fly ash or may adsorb or absorb in the product. The present work deals with the analysis of heavy metals in some samples collected from brick burning industries located in the vicinity of a metropolitan city, Peshawar, Pakistan. Samples from raw clay, product, chimney scale and fossil fuel & rubber were collected and leached with acid mixture. The leachates were concentrated and analyzed by atomic absorption spectrophotometer for the determination of chromium (Cr), lead (Pb), cadmium (Cd) and antimony (Sb). It was observed that heavy metals are present in clay, brick and chimney scale. However, significant amount of these metals was observed in chimney scale. It is inferred that such emanations laden with heavy metals are accompanying the stack gases which are being dumped in to the environment. In order to avoid environmental problems, strict environmental regulations shall be enforced and a constant check on these emanations to the environment must be made to ensure clean air act. PMID:18853266

  16. Water hyacinth as indicator of heavy metal pollution the tropics

    SciTech Connect

    Gonzalez, H.; Otero, M. ); Lodenius, M. )

    1989-12-01

    The water hyacinth (Eichhornia crassipes) is a common aquatic plant in many tropical countries. Its ability absorb nutrients and other elements from the water has made it possible to use it for water purification purposes. Eichhornia, especially stems and leaves, have been successfully used as indicators of heavy metal pollution in tropical countries. The uptake of heavy metals in this plant is stronger in the roots than in the floating shoots. Metallothionein-like compounds have been found from roots of this species after cadmium exposure. The purpose of this investigation was to study the possibilities of using roots of water hyacinth as a biological indicator of metal pollution in tropical aquatic ecosystems.

  17. Ecotoxicology of heavy metals: Liquid-phase extraction by nanosorbents

    NASA Astrophysics Data System (ADS)

    Burakov, A.; Romantsova, I.; Babkin, A.; Neskoromnaya, E.; Kucherova, A.; Kashevich, Z.

    2015-11-01

    The paper considers the problem of extreme toxicity heavy metal compounds dissolved in wastewater and liquid emissions of industrial enterprises to living organisms and environment as a whole. The possibility of increasing extraction efficiency of heavy metal ions by sorption materials was demonstrated. The porous space of the latter was modified by carbon nanotubes (CNTs) during process of the chemical vapour deposition (CVD) of carbon on metal oxide catalysts. The increasing of the sorption capacity (10-30%) and the sorption rate of nanomodified activated carbons in comparison with standard materials in the example of absorption of Co2+ and Ni2+ ions from aqueous solutions was proven.

  18. Molecular Indicators of Soil Humification and Interaction with Heavy Metals

    SciTech Connect

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

    2003-03-26

    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.

  19. Increased Tolerance to Heavy Metals Exhibited by Swarming Bacteria

    NASA Astrophysics Data System (ADS)

    Anyan, M.; Shrout, J. D.

    2014-12-01

    Pseudomonas aeruginosa is a ubiquitous, Gram-negative bacterium that utilizes several different modes of motility to colonize surfaces, including swarming, which is the coordinated movement of cells over surfaces in groups. Swarming facilitates surface colonization and biofilm development for P. aeruginosa, and it is known that swarming behavior is influenced by changes in nutrient composition and surface moisture. To understand the fate and cycling of heavy metals in the environment, it is important to understand the interaction and toxicity of these metals upon bacteria. While previous studies have shown surface-attached bacterial biofilms to be highly resistant to heavy metal toxicity, little is known about the influence of heavy metals upon surface motile bacteria and developing biofilms. Using a combination of laboratory assays we examined differences in bacterial behavior in response to two metals, Cd and Ni. We find that surface swarming bacteria are able to grow on 4x and 2.5x more Cd and Ni, respectively, than planktonic cells (i.e., test tube cultures). P. aeruginosa was able to swarm in the presence ≤0.051mM Ni and ≤0.045mM Cd. To investigate the bioavailability of metals to bacteria growing under our examined conditions, we separated cell and supernatant fractions of P. aeruginosa cultures, and used ICP-MS techniques to measure Cd and Ni sorption. A greater percentage of Cd than Ni was sorbed by both cells and supernatant (which contains rhamnolipid, a surfactant known to sorb some metals and improve swarming). While we show that cell products such as rhamnolipid bind heavy metals (as expected) and should limit metal bioavailability, our results suggest at least one additional mechanism (as yet undetermined) that promotes cell survival during swarming in the presence of these heavy metals.

  20. Characterisation and distribution of heavy metals at Masaya volcano, Nicaragua

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    Activity at Masaya volcano, Nicaragua, is characterised by periodic cycles of intense gas emission that last years to decades. The volcano entered its current phase of degassing in 1993, which resulted in a low-level persistent gas plume. As a result of this continuous emission, the substantial deposition of heavy metals onto the surrounding soils (andosols) is thought to be occurring (Delfosse et al., 2003). The deposition of these heavy metal plume components, and their incorporation into soil, is of key interest because once discharged to the environment they accumulate throughout the food chain and may pose a serious ecological threat (Alloway, 1995). Although many studies have focused on the impacts of volcanic gases on the environment, few have addressed the fate of the metals released by persistent gas plumes. This study therefore investigates the patterns of heavy metal transport, deposition and distribution at Masaya in order to provide additional information on the processes that govern the behaviour of volcanic heavy metals. A number of agricultural and non-agricultural soils at two horizons (A: 0-10 cm and B: 20-30 cm) were collected and their trace metal content analysed. Twenty sites were sampled from the active vent to ~5 km downwind, as well as two control sites upwind of the volcano. Preliminary data suggest that a rapid deposition of metals occurs close to the source, with metal concentrations in the soil generally decreasing with distance away from the active vent. Cr and As clearly follow this trend, with maximum concentrations of 20.71 and 7.61 mg/kg respectively occurring closest to the vent. Concentration peaks for Mn, Co, Ni, Cu, and Zn (959.30, 21.57, 13.44, 152.85, and 72.73 mg/kg respectively) occur slightly further away from the vent, implying that these metals are transported further. The concentration of Cr, Co, Al, Ni and Mn was found to increase from soil horizon A to B, whereas the abundance of Zn decreases with depth. Heavy metal

  1. Heavy metals in composts of separated municipal wastes

    SciTech Connect

    Liao, W.P.; Huang, W.C.; Fan, W.H.; Hsu, C.C.

    1997-12-31

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

  2. Studies on the indicator for heavy metal contamination in environments (1) heavy metal contents of hair, nail and moustache

    SciTech Connect

    Nishihara, T.; Watabe, K.; Ichikawa, T.; Kondo, M.; Fujii, M.

    1985-01-01

    Heavy metals (Hg, Pb, Cd, Cu, Ni, Fe, Zn, and Mn) contents of the samples from 10 males were followed throughout a year. The values were characteristic of the individuals, and some correlations between the contents of different metals were shown.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed

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

    2014-09-15

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

  5. [Immobilization impact of different fixatives on heavy metals contaminated soil].

    PubMed

    Wu, Lie-shan; Zeng, Dong-mei; Mo, Xiao-rong; Lu, Hong-hong; Su, Cui-cui; Kong, De-chao

    2015-01-01

    Four kinds of amendments including humus, ammonium sulfate, lime, superphosphate and their complex combination were added to rapid immobilize the heavy metals in contaminated soils. The best material was chosen according to the heavy metals' immobilization efficiency and the Capacity Values of the fixative in stabilizing soil heavy metals. The redistributions of heavy metals were determined by the European Communities Bureau of Referent(BCR) fraction distribution experiment before and after treatment. The results were as follows: (1) In the single material treatment, lime worked best with the dosage of 2% compared to the control group. In the compound amendment treatments, 2% humus combined with 2% lime worked best, and the immobilization efficiency of Pb, Cu, Cd, Zn reached 98.49%, 99.40%, 95.86%, 99.21%, respectively. (2) The order of Capacity Values was lime > humus + lime > ammonium sulfate + lime > superphosphate > ammonium sulfate + superphosphate > humus + superphosphate > humus > superphosphate. (3) BCR sequential extraction procedure results indicated that 2% humus combined with 2% lime treatment were very effective in immobilizing heavy metals, better than 2% lime treatment alone. Besides, Cd was activated firstly by 2% humus treatment then it could be easily changed into the organic fraction and residual fraction after the subsequent addition of 2% lime. PMID:25898680

  6. Thermal treatment of harzardous waste for heavy metal recovery.

    PubMed

    Hoffmann, Gaston; Schirmer, Matthias; Bilitewski, Bernd; Kaszás Savos, Melania

    2007-07-16

    In this study, a new method for recovering heavy metals from hazardous waste is introduced. The process is characterized by a separation of heavy metals and residues during the thermal treatment under a sub-stoichiometric atmosphere in a rotary kiln. After leaving the rotary kiln the separated heavy metals are precipitated in a hot gas ceramic filter. Using this technology, hazardous materials, both liquids and pasty hazardous waste containing heavy metals, can be treated and a product with a quasi-raw material condition can be formed. In contrast to current methods,the harmful substances should not be immobilized and disposed. In fact, a saleable product highly concentrated with heavy metals should be formed. During preliminary investigations with a solution containing sodium chromate tetrahydrate, the process was tested in a pilot plant. Here,the separation of chromium could be demonstrated with leaching tests and characterization of the filter dust. Analysis concerning the disposability of the residues had not been carried out because only the process and the characteristic of the filter dust were in the centre of attention. PMID:17691119

  7. New trends in removing heavy metals from wastewater.

    PubMed

    Zhao, Meihua; Xu, Ying; Zhang, Chaosheng; Rong, Hongwei; Zeng, Guangming

    2016-08-01

    With the development of researches, the treatments of wastewater have reached a certain level. Whereas, heavy metals in wastewater cause special concern in recent times due to their recalcitrance and persistence in the environment. Therefore, it is important to get rid of the heavy metals in wastewater. The previous studies have provided many alternative processes in removing heavy metals from wastewater. This paper reviews the recent developments and various methods for the removal of heavy metals from wastewater. It also evaluates the advantages and limitations in application of these techniques. A particular focus is given to innovative removal processes including adsorption on abiological adsorbents, biosorption, and photocatalysis. Because these processes have leaded the new trends and attracted more and more researches in removing heavy metals from wastewater due to their high efficency, pluripotency and availability in a copious amount. In general, the applicability, characteristic of wastewater, cost-effectiveness, and plant simplicity are the key factors in selecting the most suitable method for the contaminated wastewater. PMID:27318819

  8. Heavy Metals in Seafood and Farm Produce from Uyo, Nigeria

    PubMed Central

    Orisakwe, Orish E.; Mbagwu, Herbert O. C.; Ajaezi, Godwin C.; Edet, Ukeme W.; Uwana, Patrick U.

    2015-01-01

    Objectives: This study aimed to obtain representative data on the levels of heavy metals in seafood and farm produce consumed by the general population in Uyo, Akwa Ibom State, Nigeria, a region known for the exploration and exploitation of crude oil. Methods: In May 2012, 25 food items, including common types of seafood, cereals, root crops and vegetables, were purchased in Uyo or collected from farmland in the region. Dried samples were ground, digested and centrifuged. Levels of heavy metals (lead, cadmium, nickel, cobalt and chromium) were analysed using an atomic absorption spectrophotometer. Average daily intake and target hazard quotients (THQ) were estimated. Results: Eight food items (millet, maize, periwinkle, crayfish, stock fish, sabina fish, bonga fish and pumpkin leaf) had THQ values over 1.0 for cadmium, indicating a potential health risk in their consumption. All other heavy metals had THQ values below 1.0, indicating insignificant health risks. The total THQ for the heavy metals ranged from 0.389 to 2.986. There were 14 items with total THQ values greater than 1.0, indicating potential health risks in their consumption. Conclusion: The regular consumption of certain types of farm produce and seafood available in Uyo, Akwa Ibom State, Nigeria, is likely adding to the body burden of heavy metals among those living in this region. PMID:26052462

  9. Heavy Metal Exposure Influences Double Strand Break DNA Repair Outcomes

    PubMed Central

    Morales, Maria E.; Derbes, Rebecca S.; Ade, Catherine M.; Ortego, Jonathan C.; Stark, Jeremy; Deininger, Prescott L.; Roy-Engel, Astrid M.

    2016-01-01

    Heavy metals such as cadmium, arsenic and nickel are classified as carcinogens. Although the precise mechanism of carcinogenesis is undefined, heavy metal exposure can contribute to genetic damage by inducing double strand breaks (DSBs) as well as inhibiting critical proteins from different DNA repair pathways. Here we take advantage of two previously published culture assay systems developed to address mechanistic aspects of DNA repair to evaluate the effects of heavy metal exposures on competing DNA repair outcomes. Our results demonstrate that exposure to heavy metals significantly alters how cells repair double strand breaks. The effects observed are both specific to the particular metal and dose dependent. Low doses of NiCl2 favored resolution of DSBs through homologous recombination (HR) and single strand annealing (SSA), which were inhibited by higher NiCl2 doses. In contrast, cells exposed to arsenic trioxide preferentially repaired using the “error prone” non-homologous end joining (alt-NHEJ) while inhibiting repair by HR. In addition, we determined that low doses of nickel and cadmium contributed to an increase in mutagenic recombination-mediated by Alu elements, the most numerous family of repetitive elements in humans. Sequence verification confirmed that the majority of the genetic deletions were the result of Alu-mediated non-allelic recombination events that predominantly arose from repair by SSA. All heavy metals showed a shift in the outcomes of alt-NHEJ repair with a significant increase of non-templated sequence insertions at the DSB repair site. Our data suggest that exposure to heavy metals will alter the choice of DNA repair pathway changing the genetic outcome of DSBs repair. PMID:26966913

  10. Heavy Metal Concentrations in Soils Downwind from Masaya Volcano (Nicaragua)

    NASA Astrophysics Data System (ADS)

    Delfosse, T.; Delmelle, P.; Iserentant, A.; Delvaux, B.

    2003-12-01

    Quiescently degassing volcanoes can significantly contribute to the global emission of heavy metals. In turn, substantial deposition of metals onto soils may result, possibly increasing the risk of phytotoxicity. In contrast to anthropogenic sources, the environmental impacts of airborne volcanic heavy metals and their accumulation in soils are poorly studied. Along with the degassing of S, Cl and F, Masaya volcano, Nicaragua, is also a strong source of heavy metals. Recent estimates indicate emission rates of e.g., 62 t As yr-1, 133 t Zn yr-1 and 306 t Cu yr-1 (Moune, 2002). Here, we report on the effects of heavy metal depositions on the total contents of As, Cr, Ni, Cu, Bi, Zn, Se, and Co in two groups of soils located 5 km and 15 km downwind from the volcano. These soils correspond to young Vitric Andosols and more weathered Eutric Andosols, respectively. As and Se were measured by Inductively Coupled Plasma-Atomic Emission Spectrometry after soil digestion in a trace metal unit, and Cr, Ni, Cu, Co, Bi and Zn were determined after alkaline fusion in Li-metaborate/Li-tetraborate. Results suggest that prolonged metal inputs in the vicinity of Masaya volcano have significantly increased the As, Se and Zn contents of the soils. For these elements, concentrations are about 3-5 times those measured in the parent rock materials. However, maximum concentrations in soils (i.e., 5.4 mg As kg-1, 183 mg Zn kg-1 and 0.9 mg Se kg-1) never exceed critical concentration levels as defined for cultivated soils in the UK (10, 300 and 3 mg kg-1 for As, Zn and Se, respectively). We did not detect significant enrichments in Cr, Ni, Cu, Bi, and Co. The relatively low accumulation of metals in the Masaya Andosols contrasts with the high retention of volcanic F and S inputs (Delmelle et al., 2003). Since Andosols typically show a high affinity for heavy metals, which can be bound to organic matter as well as to oxides, oxyhydroxide and allophane minerals present in these soils, rapid

  11. Community responses of aquatic insects to heavy metals

    SciTech Connect

    Clements, W.H.; Cherry, D.S.; Cairns, J.

    1987-07-01

    Community level toxicity tests were conducted in outdoor experimental streams to examine the responses of aquatic insects to heavy metals. Introduced substrates (plastic trays filled with small cobble) were colonized at several locations in a river impacted by heavy metals. After 30 d, 4delta trays from an upstream control site were transferred to 12 outdoor experimental streams. Each stream was randomly assigned to one of three treatments: control, low metals, and high metals. Two trays were removed from each stream after 4 and 10 d exposure. Community structure on these trays was compared to field data collected from control and impacted sites. Macroinvertebrate density and number of taxa were reduced in both treated streams and at impacted field sites. Owing to differences in relative sensitivity to metals, the percent composition of dominant taxa also varied among treatments.

  12. Beneficial effect of sesame oil on heavy metal toxicity.

    PubMed

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

    2014-02-01

    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-α, and interleukin-1β 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

  13. Coupling bioleaching and electrokinetics to remediate heavy metal contaminated soils.

    PubMed

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

    2015-04-01

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

  14. Effect of Heavy Metals in Plants of the Genus Brassica.

    PubMed

    Mourato, Miguel P; Moreira, Inês N; Leitão, Inês; Pinto, Filipa R; Sales, Joana R; Martins, Luisa Louro

    2015-01-01

    Several species from the Brassica genus are very important agricultural crops in different parts of the world and are also known to be heavy metal accumulators. There have been a large number of studies regarding the tolerance, uptake and defense mechanism in several of these species, notably Brassica juncea and B. napus, against the stress induced by heavy metals. Numerous studies have also been published about the capacity of these species to be used for phytoremediation purposes but with mixed results. This review will focus on the latest developments in the study of the uptake capacity, oxidative damage and biochemical and physiological tolerance and defense mechanisms to heavy metal toxicity on six economically important species: B. juncea, B. napus, B. oleracea, B. carinata, B. rapa and B. nigra. PMID:26247945

  15. Dustfall Heavy Metal Pollution During Winter in North China.

    PubMed

    Xiong, Qiu-lin; Zhao, Wen-ji; Guo, Xiao-yu; Shu, Tong-tong; Chen, Fan-tao; Zheng, Xiao-xia; Gong, Zhao-ning

    2015-10-01

    In order to study heavy metal pollution in dustfall during Winter in North China, forty-four dustfall samples were collected in North China Region from November 2013 to March 2014. Then forty trace elements content were measured for each sample by inductively coupled plasma-mass spectrometry. Finally, the contamination characteristics of the main heavy metals were studied through a multi-method analysis, including variability analysis, Pearson correlation analysis and principal component analysis. Results showed that the relative contents of cadmium (Cd), zinc (Zn), copper (Cu), bismuth (Bi), lead (Pb) exceeded the standards stipulated in Chinese soil elements background values by amazing 4.9 times. In this study, conclusions were drawn that dustfall heavy metal pollution in the region was mainly caused by transport pollution, metallurgy industrial pollution, coal pollution and steel industrial pollution. PMID:26215458

  16. Effect of Heavy Metals in Plants of the Genus Brassica

    PubMed Central

    Mourato, Miguel P.; Moreira, Inês N.; Leitão, Inês; Pinto, Filipa R.; Sales, Joana R.; Louro Martins, Luisa

    2015-01-01

    Several species from the Brassica genus are very important agricultural crops in different parts of the world and are also known to be heavy metal accumulators. There have been a large number of studies regarding the tolerance, uptake and defense mechanism in several of these species, notably Brassica juncea and B. napus, against the stress induced by heavy metals. Numerous studies have also been published about the capacity of these species to be used for phytoremediation purposes but with mixed results. This review will focus on the latest developments in the study of the uptake capacity, oxidative damage and biochemical and physiological tolerance and defense mechanisms to heavy metal toxicity on six economically important species: B. juncea, B. napus, B. oleracea, B. carinata, B. rapa and B. nigra. PMID:26247945

  17. Baker's yeast assay procedure for testing heavy metal toxicity

    SciTech Connect

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

    1984-01-01

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

  18. Heavy metals in the soil-crop system

    NASA Astrophysics Data System (ADS)

    Il'in, V. B.

    2007-09-01

    Data on the bulk contents of heavy metals in polluted soils are not quite suitable to judge the ecological situation in an agrocenosis. According to the results of model experiments with artificial contamination of soil, the flux of zinc and lead from the starting point (from a medium loamy leached chernozem) to the final point (wheat grains) sharply decreases. It is possible to obtain an ecologically pure (uncontaminated) grain yield even on a strongly contaminated soil due to the buffering capacity of the latter and due to the self-protective capacity of agricultural crops. The ecological potential of the soil-crop system is formed mostly at the expense of the buffering capacity of soil to heavy metals; the barrier function of plants is less significant. It is argued that the existing ecological standards based on the total contents of heavy metals in soil are of little use for predicting the quality of crops.

  19. Separation Characteristics of Heavy Metal Compounds by Hot Gas Cleaning System

    SciTech Connect

    Sakano, T.; Kanaoka, C.; Furuuchi, M.; Yang, K-S.; Hata, M.

    2002-09-20

    The purpose of this research is the basic study for the development of separation technology of heavy metal compounds from hot flue gas. While the hot flue gas containing heavy metals from a melting furnace of industrial waste passes through the high temperature dust collector which can be varied the operating temperature. The heavy metals can be separated due to different boiling point of each heavy metal. On the basis of this concept, the concentration of heavy metals in the flue gas were sampled and measured at inlet, outlet of the ceramic filter housing in the actual industrial waste processing system. Speciation of heavy metals in collected ashes was clarified by separating heavy metals according to compounds using their elution characteristics. Moreover, equilibrium analysis was performed to determine the effect of temperature, flue gases conditions on heavy metals speciation, and it was compared with experimental data. From these results, we discussed about separation performance of heavy metal compounds by hot gas cleaning.

  20. Assessment of Heavy Metal Pollution in Topsoil around Beijing Metropolis

    PubMed Central

    Sun, Ranhao; Chen, Liding

    2016-01-01

    The topsoil around Beijing metropolis, China, is experiencing impacts of rapid urbanization, intensive farming, and extensive industrial emissions. We analyzed the concentrations of Cu, Ni, Pb, Zn, Cd, and Cr from 87 topsoil samples in the pre-rainy season and 115 samples in the post-rainy season. These samples were attributed to nine land use types: forest, grass, shrub, orchard, wheat, cotton, spring maize, summer maize, and mixed farmland. The pollution index (PI) of heavy metals was calculated from the measured and background concentrations. The ecological risk index (RI) was assessed based on the PI values and toxic-response parameters. The results showed that the mean PI values of Pb, Cr, and Cd were > 1 while those of Cu, Ni, and Zn were < 1. All the samples had low ecological risk for Cu, Ni, Pb, Zn, and Cr while only 15.35% of samples had low ecological risk for Cd. Atmospheric transport rather than land use factors best explained the seasonal variations in heavy metal concentrations and the impact of atmospheric transport on heavy metal concentrations varied according to the heavy metal types. The concentrations of Cu, Cd, and Cr decreased from the pre- to post-rainy season, while those of Ni, Pb, and Zn increased during this period. Future research should be focused on the underlying atmospheric processes that lead to these spatial and seasonal variations in heavy metals. The policymaking on environmental management should pay close attention to potential ecological risks of Cd as well as identifying the transport pathways of different heavy metals. PMID:27159454

  1. Heavy Metals in the Environment-Historical Trends

    NASA Astrophysics Data System (ADS)

    Callender, E.

    2003-12-01

    These six metals, commonly classified as heavy metals, are a subset of a larger group of trace elements that occur in low concentration in the Earth's crust. These heavy metals were mined extensively for use in the twentieth century Industrial Society. Nriagu (1988a) estimated that between 0.5 (Cd) and 310 (Cu) million metric tons of these metals were mined and ultimately deposited in the biosphere. In many instances, the inputs of these metals from anthropogenic sources exceed the contributions from natural sources (weathering, volcanic eruptions, forest fires) by several times ( Adriano, 1986). In this chapter, heavy metals (elements having densities greater than 5) and trace elements (elements present in the lithosphere in concentrations less than 0.1%) are considered synonymous.It has been observed in the past that the rate of emission of these trace metals into the atmosphere is low due to their low volatility. However, with the advent of large-scale metal mining and smelting as well as fossil-fuel combustion in the twentieth century, the emission rate of these metals has increased dramatically. As most of these emissions are released into the atmosphere where the mammals live and breathe, we see a great increase in the occurrence of health problems such as lead (Pb) poisoning, cadmium (Cd) Itai-itai disease, chromium (Cr), and nickel (Ni) carcinogenesis.In this chapter, the author has attempted to present a synopsis of the importance of these metals in the hydrocycle, their natural and anthropogenic emissions into the environment, their prevalent geochemical form incorporated into lacustrine sediments, and their time-trend distributions in watersheds that have been impacted by urbanization, mining and smelting, and other anthropogenic activities. These time trends are reconstructed from major-minor-trace-element distributions in age-dated sediment cores, mainly from reservoirs where the mass sedimentation rates (MSRs) are orders of magnitude greater than

  2. Brassinosteroids and Response of Plants to Heavy Metals Action.

    PubMed

    Rajewska, Iwona; Talarek, Marta; Bajguz, Andrzej

    2016-01-01

    Brassinosteroids (BRs) are a widespread group of plant hormones. These phytohormones play a crucial role in the regulation of growth and development of various plant species, and they demonstrate high biological activity. BRs are considered to demonstrate protective activity in the plants exposed to various stresses. Due to rapid industrialization and urbanization, heavy metals have become one of the most important plant stressors. In plants, accumulation of heavy metals beyond the critical levels leads to oxidative stress. However, BRs may inhibit the degradation of lipids, resulted from the overproduction of reactive oxygen species under stress conditions, and increase the activity of antioxidants. They also have the ability to promote phytochelatins synthesis. PMID:27242833

  3. Oil palm biomass as an adsorbent for heavy metals.

    PubMed

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

    2014-01-01

    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

  4. Adsorption of heavy metals on sonicated activated sludge.

    PubMed

    Commenges-Bernole, N; Marguerie, J

    2009-01-01

    The objective of this work is to assess heavy metals fixation capacity on sonicated activated sludge. Ultrasonic treatment of sludge has lead to its desintegration and changes physico-chemical characteristics such as soluble chemical oxygen demand, proteins or particle size distribution. This study has shown that these modifications have improved significantly the capacity of sludge to fix heavy metals. Indeed, after a sonication of 15 min and storage of three days after irradiation, the equilibrium capacity is increased about 45%. The restructuration of sludge during the storage seems to increase the accessibility to active binding sites. PMID:18599337

  5. Brassinosteroids and Response of Plants to Heavy Metals Action

    PubMed Central

    Rajewska, Iwona; Talarek, Marta; Bajguz, Andrzej

    2016-01-01

    Brassinosteroids (BRs) are a widespread group of plant hormones. These phytohormones play a crucial role in the regulation of growth and development of various plant species, and they demonstrate high biological activity. BRs are considered to demonstrate protective activity in the plants exposed to various stresses. Due to rapid industrialization and urbanization, heavy metals have become one of the most important plant stressors. In plants, accumulation of heavy metals beyond the critical levels leads to oxidative stress. However, BRs may inhibit the degradation of lipids, resulted from the overproduction of reactive oxygen species under stress conditions, and increase the activity of antioxidants. They also have the ability to promote phytochelatins synthesis. PMID:27242833

  6. Progress in heavy metal fluoride glasses for infrared fibers

    NASA Astrophysics Data System (ADS)

    Drexhage, M. G.; El-Bayoumi, O. H.; Moynihan, C. T.

    1982-12-01

    The optical and physical characteristics of heavy metal fluoride glasses are reviewed with reference to recent laboratory experiments. In particular, attention is given to comparative optical studies of fluorozirconate and fluorohafnate glasses, refractive index and material dispersion of fluoride glasses, and preliminary results of optical studies of heavy metal fluoride glasses not containing ZrF4 or HfF4. The latter sometimes exhibit extended transparency in the mid-IR relative to that observed in fluorozirconate and fluorohafnate glasses. The effect of the AlF4 content on the optical properties of BaF2/ThF4 glasses is discussed.

  7. Can heavy metal pollution defend seed germination against heat stress? Effect of heavy metals (Cu(2+), Cd(2+) and Hg(2+)) on maize seed germination under high temperature.

    PubMed

    Deng, Benliang; Yang, Kejun; Zhang, Yifei; Li, Zuotong

    2016-09-01

    Heavy metal pollution, as well as greenhouse effect, has become a serious threat today. Both heavy metal and heat stresses can arrest seed germination. What response can be expected for seed germination under both stress conditions? Here, the effects of heavy metals (Cu(2+), Cd(2+) and Hg(2+)) on maize seed germination were investigated at 20 °C and 40 °C. Compared with 20 °C, heat stress induced thermodormancy. However, this thermodormancy could be significantly alleviated by the addition of a low concentration of heavy metals. Heavy metals, as well as heat stress induced H2O2 accumulation in germinating seeds. Interestingly, this low concentration of heavy metal that promoted seed germination could be partly blocked by DMTU (a specific ROS scavenger), irrespective of temperature. Accordingly, H2O2 addition reinforced this promoting effect on seed germination, which was induced by a low concentration of heavy metal. Furthermore, we found that the NADPH oxidase derived ROS was required for seed germination promoted by the heavy metals. Subsequently, treatment of seeds with fluridone (a specific inhibitor of ABA) or ABA significantly alleviated or aggravated thermodormancy, respectively. However, this alleviation or aggravation could be partly attenuated by a low concentration of heavy metals. In addition, germination that was inhibited by high concentrations of heavy metals was also partly reversed by fluridone. The obtained results support the idea that heavy metal-mediated ROS and hormone interaction can finally affect the thermodormancy release or not. PMID:27239687

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

    SciTech Connect

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

    2014-01-30

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

  9. Heavy metal characterization of circulating fluidized bed derived biomass ash.

    PubMed

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

    2012-09-30

    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

  10. Coal burning leaves toxic heavy metal legacy in the Arctic

    SciTech Connect

    McConnell, J.R.; Edwards, R.

    2008-08-26

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

  11. Phytoremediation of heavy metal contaminated soil by Jatropha curcas.

    PubMed

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

    2014-12-01

    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

  12. Chelate-Assisted Heavy Metal Movement Through the Root Zone

    NASA Astrophysics Data System (ADS)

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

    2001-12-01

    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.

  13. Removal of heavy metal from industrial effluents using Baker's yeast

    NASA Astrophysics Data System (ADS)

    Ferdous, Anika; Maisha, Nuzhat; Sultana, Nayer; Ahmed, Shoeb

    2016-07-01

    Bioremediation of wastewater containing heavy metals is one of the major challenges in environmental biotechnology. Heavy metals are not degraded and as a result they remain in the ecosystem, and pose serious health hazards as it comes in contact with human due to anthropogenic activities. Biological treatment with various microorganisms has been practiced widely in recent past, however, accessing and maintaining the microorganisms have always been a challenge. Microorganisms like Baker's yeast can be very promising biosorbents as they offer high surface to volume ratio, large availability, rapid kinetics of adsorption and desorption and low cost. The main aim of this study is to evaluate the applicability of the biosorption process using baker's yeast. Here we present an experimental investigation of biosorption of Chromium (Cr) from water using commercial Baker's Yeast. It was envisaged that yeast, dead or alive, would adsorb heavy metals, however, operating parameters could play vital roles in determining the removal efficiency. Parameters, such as incubation time, pH, amount of biosorbent and heavy metal concentration were varied to investigate the impacts of those parameters on removal efficiency. Rate of removal was found to be inversely proportional to the initial Cr (+6) concentrations but the removal rate per unit biomass was a weakly dependent on initial Cr(+6) concentrations. Biosorption process was found to be more efficient at lower pH and it exhibited lower removal with the increase in solution pH. The optimum incubation time was found to be between 6-8 hours and optimum pH for the metal ion solution was 2. The effluents produced in leather industries are the major source of chromium pollution in Bangladesh and this study has presented a very cost effective yet efficient heavy metal removal approach that can be adopted for such kind of wastewater.

  14. Immunotoxicity of heavy metals in relation to Great Lakes.

    PubMed Central

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

    1995-01-01

    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

  15. Mechanisms of heavy metal removal using microorganisms as biosorbent.

    PubMed

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

    2014-01-01

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

  16. Flow through luminescence for heavy metal analysis in seawater

    NASA Astrophysics Data System (ADS)

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

    1999-12-01

    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 fluorescence) gives rise to high sensitive, selective and innovative approaches which could be used to develop new trace metal sensing methods. In this way, we have observed that the metal-chelates formed between different sulphonic-hydroxyquinolines with heavy metals, such as lead, or the metal-chelates between mercury and purines exhibit strong room temperature phosphorescence and fluorescence, respectively. Based on the formation of such quelates, two luminescence methods are investigated for sensing of lead and mercury in seawater. Optimum experimental conditions and the analytical performance characteristics of the methods are discussed. Relative standard deviations in the order of 4% are typical at 100 ng mL-1 of Pb(II) and Hg (II). The detection limits are 0.1 and 1.4 ng mL-1 for lead and mercury, respectively. Possible interferences present in seawater, including sea water cations and anions are evaluated in detail. Finally, the methods are applied to the determination de mercury and lead in seawater samples.

  17. Heavy Metal Tolerance in Stenotrophomonas maltophilia

    PubMed Central

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

    2008-01-01

    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

  18. Using biopolymers to remove heavy metals from soil and water

    SciTech Connect

    Krishnamurthy, S.; Frederick, R.M.

    1993-11-19

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

  19. Heavy metal resistant strains are widespread along Streptomyces phylogeny.

    PubMed

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

    2013-03-01

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

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

    NASA Astrophysics Data System (ADS)

    Ilić, Ivana; Bogdanović, Dejan; Živković, Dragana; Milošević, Novica; Todorović, Boban

    2011-07-01

    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.

  1. ULTRASONIC ENHANCEMENT OF THE REMOVAL OF HEAVY METALS

    EPA Science Inventory

    EPA GRANT NUMBER: R828598C020
    Title: Ultrasonic Enhancement of the Removal of Heavy Metals
    Investigators: Dennis Truax, Krishnan Balasubramaniam
    Institution: Mississippi State University
    EPA Project Officer: S. Bala Krishnan
    ...

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

    USGS Publications Warehouse

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

    1973-01-01

    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.

  3. MICROBIAL SEQUESTRATION OF LEAD AND OTHER HEAVY METALS

    EPA Science Inventory

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

  4. Heavy metal contamination in the Delhi segment of Yamuna basin.

    PubMed

    Sehgal, Meena; Garg, Ankur; Suresh, R; Dagar, Priya

    2012-01-01

    Concentration of heavy metals (Cd, Ni, Zn, Fe, Cu, Mn, Pb, Cr, Hg and As) in the waters of River Yamuna and in the soil of agricultural fields along its course in Delhi are reported from 13 sites, spread through the Delhi stretch of Yamuna, starting from the Wazirabad barrage till the Okhla barrage. Varying concentration of heavy metals was found. Peaks were observed in samples collected downstream of Wazirabad and Okhla barrage, indicating the anthropogenic nature of the contamination. The Wazirabad section of the river receives wastewater from Najafgarh and its supplementary drains, whereas the Shahdara drain releases its pollution load upstream of the Okhla barrage. Average heavy metal concentration at different locations in the river water varied in the order of Fe>Cr>Mn>Zn>Pb>Cu>Ni>Hg>As>Cd. The river basin soil shows higher level of contamination with lesser variation than the water samples among sampling locations, thereby suggesting deposition over long periods of time through the processes of adsorption and absorption. The average heavy metal concentration at different locations in soil varied in the order of Fe>Mn>Zn>Cr>Pb>Ni>Hg>Cu>As>Cd. PMID:21505769

  5. HEAVY METAL CONTENT OF AYURVEDIC HERBAL MEDICINE PRODUCTS

    EPA Science Inventory

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

  6. TREATMENT OF HEAVY METALS USING AN ORGANIC SULFATE REDUCING PRB

    EPA Science Inventory

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

  7. Screening Capsicum chinense fruits for heavy metals bioaccumulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. 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...

  9. Fate of heavy metals and agrochemicals in biochar amended soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    ERIC Educational Resources Information Center

    Arnett, Jeffrey

    1991-01-01

    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)

  11. Anaerobes into heavy metal: Dissimilatory metal reduction in anoxic environments

    USGS Publications Warehouse

    Lovley, D.R.

    1993-01-01

    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.

  12. PROCESS FOR SEPARATION OF HEAVY METALS

    DOEpatents

    Duffield, R.B.

    1958-04-29

    A method is described for separating plutonium from aqueous acidic solutions of neutron-irradiated uranium and the impurities associated therewith. The separation is effected by adding, to the solution containing hexavalent uranium and plutonium, acetate ions and the ions of an alkali metal and those of a divalent metal and thus forming a complex plutonium acetate salt which is carried by the corresponding complex of uranium, such as sodium magnesium uranyl acetate. The plutonium may be separated from the precipitated salt by taking the same back into solution, reducing the plutonium to a lower valent state on reprecipitating the sodium magnesium uranyl salt, removing the latter, and then carrying the plutonium from ihe solution by means of lanthanum fluoride.

  13. Utilizing heavy metal-laden water hyacinth biomass in vermicomposting.

    PubMed

    Tereshchenko, Natalya N; Akimova, Elena E; Pisarchuk, Anna D; Yunusova, Tatyana V; Minaeva, Oksana M

    2015-05-01

    We studied the efficiency of water treatment by water hyacinth (Eichhornia crassipes) from heavy metals (Zn, Cd, Pb, Cu), as well as a possibility of using water hyacinth biomass obtained during treatment for vermicomposting by Eisenia fetida and the vermicompost quality in a model experiment. The results showed that the concentration of heavy metals in the trials with water hyacinth decreased within 35 days. We introduced water hyacinth biomass to the organic substrate for vermicomposting, which promoted a significant weight gain of earthworms and growth in their number, as well as a 1.5- to 3-fold increase in coprolite production. In the trial with 40 % of Eichhornia biomass in the mixture, we observed a 26-fold increase in the number and a 16-fold weight gain of big mature individuals with clitellum; an increase in the number of small individuals 40 times and in the number of cocoons 140 times, as compared to the initial substrate. The utilization of water hyacinth biomass containing heavy metals in the mixture led to a 10-fold increase in the number of adult individuals and cocoons, which was higher than in control. We found out that adding 10 % of Eichhornia biomass to the initial mixture affected slightly the number of microorganisms and their species diversity in the vermicompost. Adding Eichhornia biomass with heavy metals reduced the total number of microorganisms and sharply diminished their species diversity. In all trials, adding water hyacinth in the mixture for vermicomposting had a positive impact on wheat biometric parameters in a 14-day laboratory experiment, even in the trial with heavy metals. PMID:25501861

  14. Disposable cuvette test for enzymatic determination of heavy metals

    NASA Astrophysics Data System (ADS)

    Wolfbeis, Otto S.; Preininger, Claudia

    1995-10-01

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

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

    PubMed

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

    2015-02-15

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

  16. Heavy metals in sediments of the Tecate River, Mexico

    NASA Astrophysics Data System (ADS)

    Wakida, F. T.; Lara-Ruiz, D.; Temores-Peña, J.; Rodriguez-Ventura, J. G.; Diaz, C.; Garcia-Flores, E.

    2008-04-01

    Ten sites along the Tecate River, Mexico were sampled to evaluate the cadmium, lead, nickel and chromium concentrations in sediments. The result shows contamination for cadmium in most of the sites, where two sites were class 4 (polluted to strongly polluted) according to geoaccumulation index proposed by Muller. Two sites were found polluted for all the heavy metals analyzed (Cr, Cd, Pb and Ni), indicating the effect of anthropogenic activities. A correlation between Ni and Cd concentration had been found indicating a common source. These metals are usually used in electroplating industry. The results of this study can be used for decision makers to prioritize measures to control the pollution for these metals.

  17. Simultaneous heavy metal removal mechanism by dead macrophytes.

    PubMed

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

    2006-01-01

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

  18. Two-stage anaerobic digestion enables heavy metal removal.

    PubMed

    Selling, Robert; Håkansson, Torbjörn; Björnsson, Lovisa

    2008-01-01

    To fully exploit the environmental benefits of the biogas process, the digestate should be recycled as biofertiliser to agriculture. This practice can however be jeopardized by the presence of unwanted compounds such as heavy metals in the digestate. By using two-stage digestion, where the first stage includes hydrolysis/acidification and liquefaction of the substrate, heavy metals can be transferred to the leachate. From the leachate, metals can then be removed by adsorption. In this study, up to 70% of the Ni, 40% of the Zn and 25% of the Cd present in maize was removed when the leachate from hydrolysis was circulated over a macroporous polyacrylamide column for 6 days. For Cu and Pb, the mobilization in the hydrolytic stage was lower which resulted in a low removal. A more efficient two-stage process with improved substrate hydrolysis would give lower pH and/or longer periods with low pH in the hydrolytic stage. This is likely to increase metal mobilisation, and would open up for an excellent opportunity of heavy metal removal. PMID:18359995

  19. Bismuth nanoparticles integration into heavy metal electrochemical stripping sensor.

    PubMed

    Cadevall, Miquel; Ros, Josep; Merkoçi, Arben

    2015-08-01

    Between their many applications bismuth nanoparticles (BiNPs) are showing interest as pre-concentrators in heavy metals detection while being applied as working electrode modifiers used in electrochemical stripping analysis. From the different reported methods to synthesize BiNPs we are focused on the typical polyol method, largely used in these types of metallic and semi-metallic nanoparticles. This study presents the strategy for an easy control of the shape and size of BiNPs including nanocubes, nanosferes and triangular nanostructures. To improve the BiNP size and shape, different reducing agents (ethylene glycol or sodium hypophosphite) and stabilizers (polyvinyl pyrrolidone, PVP, in different amounts) have been studied. The efficiency of BiNPs for heavy metals analysis in terms of detection sensitivity while being used as modifiers of screen-printed carbon electrodes including the applicability of the developed device in real sea water samples is shown. A parallel study between the obtained nanoparticles and their performance in heavy metal sensing has been described in this communication. PMID:25994368

  20. A review of heavy metal adsorption by marine algae

    NASA Astrophysics Data System (ADS)

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

    2000-09-01

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

  1. Plasma polymer-functionalized silica particles for heavy metals removal.

    PubMed

    Akhavan, Behnam; Jarvis, Karyn; Majewski, Peter

    2015-02-25

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

  2. 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, ...

  3. A sensitive rapid on-site immunoassay for heavy metal contamination

    SciTech Connect

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

    1996-05-02

    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.

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

    PubMed Central

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

    2014-01-01

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

  5. Nutrients and heavy metals distribution in thermally treated pig manure.

    PubMed

    Kuligowski, Ksawery; Poulsen, Tjalfe G; Stoholm, Peder; Pind, Niels; Laursen, Jens

    2008-08-01

    Ash from pig manure treated by combustion and thermal gasification was characterized and compared in terms of nutrient, i.e., potassium (K), phosphorus (P) and heavy metal, i.e., cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) contents. Total nutrient and metal concentrations were measured using energy dispersive X-ray fluorescence analysis. Acid (HNO3, H2SO4) and water-extractable concentrations were also measured both in non-classified ash and in selected ash particle size fractions using flame atomic absorption spectrometry and colorimetric spectrometry. Results indicate that ash from gasified manure contained more water-extractable K in comparison with combusted manure whereas the opposite was the case with respect to P. Heavy metals Ni, Cr and Cd were present in higher concentrations in the fine particle size fractions (< 30 microm of particle diameter), whereas K, P, Zn and Cu exhibited higher concentrations in the coarser particle size fractions (> 30 microm). PMID:18727326

  6. Characterization of bacterial communities in heavy metal contaminated soils.

    PubMed

    Roane, T M; Kellogg, S T

    1996-06-01

    Heavy metal pollution is a principle source of environmental contamination. We analyzed heavy metal impacted soil microbial communities and found that, in general, although lead adversely affected biomass, metabolic activity, and diversity, autochthonous lead- and cadmium-resistant isolates were found. In several metal-stressed soils, the microbial community consisted of two populations, either resistant or sensitive to lead. Additionally, a lead-resistant isolate was isolated from a control soil with no known previous exposure to lead, suggesting widespread lead resistance. Lead-resistant genera isolated included Pseudomonas, Bacillus, Corynebacterium, and Enterobacter species. Plasmids, ranging from 5 to 260 kb, were not detected through standard purifications from lead-resistant isolates. Positive correlations existed between antibiotic resistance and isolation habitat for lead-resistant strains, microbial metabolic activity and soil type, soluble lead concentration and microbial diversity, and arsenic concentration and total or viable cell concentrations. PMID:8801006

  7. Intelligent potentiostat for identification of heavy metals in situ

    NASA Astrophysics Data System (ADS)

    Christidis, K.; Gow, K.; Robertson, P.; Pollard, P.

    2006-01-01

    This article presents a low-cost portable electrochemical instrument capable of on-site identification of heavy metals. The instrument acquires metal-specific voltage and current signals by the application of differential pulse anodic stripping voltammetry. This technique enhances the analytical current and rejects the background current, resulting in a higher signal-to-noise ratio for a better detection limit. The identification of heavy metals is based on an intelligent machine-based method using a multilayer perceptron neural network consisting of three layers of neurons. The neural network is implemented using a 16 bit microcontroller. The system is developed for use in the field in order to avoid expensive and time-consuming procedures and can be used in a variety of situations to help environmental assessment and control.

  8. Removal of heavy metals by hybrid electrocoagulation and microfiltration processes.

    PubMed

    Keerthi; Vinduja, V; Balasubramanian, N

    2013-01-01

    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

  9. Heavy metal stress and some mechanisms of plant defense response.

    PubMed

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

    2015-01-01

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

  10. Toxicity, mechanism and health effects of some heavy metals

    PubMed Central

    Jaishankar, Monisha; Tseten, Tenzin; Anbalagan, Naresh; Beeregowda, Krishnamurthy N.

    2014-01-01

    Heavy metal toxicity has proven to be a major threat and there are several health risks associated with it. The toxic effects of these metals, even though they do not have any biological role, remain present in some or the other form harmful for the human body and its proper functioning. They sometimes act as a pseudo element of the body while at certain times they may even interfere with metabolic processes. Few metals, such as aluminium, can be removed through elimination activities, while some metals get accumulated in the body and food chain, exhibiting a chronic nature. Various public health measures have been undertaken to control, prevent and treat metal toxicity occurring at various levels, such as occupational exposure, accidents and environmental factors. Metal toxicity depends upon the absorbed dose, the route of exposure and duration of exposure, i.e. acute or chronic. This can lead to various disorders and can also result in excessive damage due to oxidative stress induced by free radical formation. This review gives details about some heavy metals and their toxicity mechanisms, along with their health effects. PMID:26109881

  11. Phytoremediation potential of Lemna minor L. for heavy metals.

    PubMed

    Bokhari, Syeda Huma; Ahmad, Iftikhar; Mahmood-Ul-Hassan, Muhammad; Mohammad, Ashiq

    2016-01-01

    Phytoremediation potential of L. minor for cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) from two different types of effluent in raw form was evaluated in a glass house experiment using hydroponic studies for a period of 31 days. Heavy metals concentration in water and plant sample was analyzed at 3, 10, 17, 24, and 31 day. Removal efficiency, metal uptake and bio-concentration factor were also calculated. Effluents were initially analyzed for physical, chemical and microbiological parameters and results indicated that municipal effluent (ME) was highly contaminated in terms of nutrient and organic load than sewage mixed industrial effluent (SMIE). Results confirmed the accumulation of heavy metals within plant and subsequent decrease in the effluents. Removal efficiency was greater than 80% for all metals and maximum removal was observed for nickel (99%) from SMIE. Accumulation and uptake of lead in dry biomass was significantly higher than other metals. Bio-concentration factors were less than 1000 and maximum BCFs were found for copper (558) and lead (523.1) indicated that plant is a moderate accumulator of both metals. Overall, L. minor showed better performance from SMIE and was more effective in extracting lead than other metals. PMID:26114480

  12. Heavy Metal Stress and Some Mechanisms of Plant Defense Response

    PubMed Central

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

    2015-01-01

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

  13. Heavy metal speciation and toxicity characteristics of tannery sludge

    NASA Astrophysics Data System (ADS)

    Juel, Md. Ariful Islam; Chowdhury, Zia Uddin Md.; Ahmed, Tanvir

    2016-07-01

    Heavy metals present in tannery sludge can get mobilized in the environment in various forms and can be a cause for concern for the natural ecosystem and human health. The speciation of metals in sludge provides valuable information regarding their toxicity in the environment and determines their suitability for land application or disposal in landfills. Concentrations of seven heavy metals (Cr, Pb, Cd, Ni, Zn, As and Cu) in tannery sludge were determined to evaluate their toxicity levels. Metal contents ranged over the following intervals: As: 1.52-2.07 mg/kg; Pb: 57.5-67 mg/kg; Cr: 15339-26501 mg/kg; Cu: 261.3-579.5 mg/kg; Zn: 210.2-329.1 mg/kg and Ni: 137.5-141.3 mg/kg (dry weight basis). The concentrations of all heavy metals in the sludge samples were lower compared to EPA guidelines except chromium which was found to be several orders of magnitude higher than the guideline value. Toxicity Characteristics Leaching Procedure (TCLP) test indicated that the leaching potential of chromium was higher compared to the other heavy metals and exceeded the EPA land disposal restriction limits. To quantitatively assess the environmental burden of the chromium associated with tannery sludge, the IMPACT 2002+ methodology was adopted under the SimaPro software environment. Considering the USEPA limit for chromium as the baseline scenario, it was found that chromium in the tannery sludge had 6.41 times higher impact than the baseline in the categories of aquatic ecotoxicity, terrestrial ecotoxicity and non-carcinogens. Chromium has the highest contribution to toxicity in the category of aquatic ecotoxicity while copper is the major contributor to the category of terrestrial ecotoxicity in the tannery sludge.

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

    PubMed Central

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

    2007-01-01

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

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

    PubMed

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

    2007-01-01

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

  16. Concentration of heavy metals in ash produced from Lithuanian forests

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

    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

  17. Beneficial role of bacterial endophytes in heavy metal phytoremediation.

    PubMed

    Ma, Ying; Rajkumar, Mani; Zhang, Chang; Freitas, Helena

    2016-06-01

    Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up pollutants from the soil, water and air. In recent years, phytoremediation assisted by bacterial endophytes has been highly recommended for cleaning up of metal polluted soils since endophytic bacteria can alleviate metal toxicity in plant through their own metal resistance system and facilitate plant growth under metal stress. Endophytic bacteria improve plant growth in metal polluted soils in two different ways: 1) directly by producing plant growth beneficial substances including solubilization/transformation of mineral nutrients (phosphate, nitrogen and potassium), production of phytohormones, siderophores and specific enzymes; and 2) indirectly through controlling plant pathogens or by inducing a systemic resistance of plants against pathogens. Besides, they also alter metal accumulation capacity in plants by excreting metal immobilizing extracellular polymeric substances, as well as metal mobilizing organic acids and biosurfactants. The present work aims to review the progress of recent research on the isolation, identification and diversity of metal resistant endophytic bacteria and illustrate various mechanisms responsible for plant growth promotion and heavy metal detoxification/phytoaccumulation/translocation in plants. PMID:26989941

  18. Concentration and speciation of heavy metals during water hyacinth composting.

    PubMed

    Singh, Jiwan; Kalamdhad, Ajay S

    2012-11-01

    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

  19. Characterization of heavy metal particles embedded in tire dust.

    PubMed

    Adachi, Kouji; Tainosho, Yoshiaki

    2004-10-01

    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

  20. Bioaccumulation and toxicity of heavy metals and trace elements. [Water pollution

    SciTech Connect

    Murphy, C.B. Jr.; Spiegel, S.J.

    1982-06-01

    A review of the literature dealing with the biological accumulation and toxicity of heavy metals in aquatic ecosystems is presented. The review first examines the sources of heavy metals and the process of ecological concentration of these pollutants. The biological effects of cadmium, copper, and zinc on fish and invertebrates are considered in detail. Methods of detoxification of heavy metals are presented. (KRM)

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

    PubMed

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

    2014-06-01

    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

  2. Heavy metals in Ratnapura alluvial gem sediments, Sri Lanka

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    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 <63μm 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

  3. Heavy metals in garden soils along roads in Szeged, Hungary

    NASA Astrophysics Data System (ADS)

    Szolnoki, Zsuzsanna; Farsang, Andrea

    2010-05-01

    The soils of the urban environment, owing to the various anthropogenic activities, can be contaminated by heavy metals. The traffic is well-known for more decades to be main source of heavy metals mostly in cities. The accumulation of these elements can have different effects, either directly endangering the natural soil functions, or indirectly endangering the biosphere by bio-accumulation and inclusion in the food chain. The hobby gardens and the vegetable gardens directly along roads can be potential risky for people since unknown amount of heavy metals can be accumulated into organization of local residents due to consumption of vegetables and fruits grown in their own garden. The aim of this study was to determine the heavy metal content of garden soils directly along roads with heavy traffic in order to assess possible risk for human health. The total content and the mobile content of Cd, Co, Cr, Cu, Ni, Pb and Zn have been determined in samples from garden soils along 5 busy roads of Szeged, South Hungary. Enrichment factor has been calculated with the help of control soil samples far from roads. The soil properties basically influencing on metal mobility have also been examined. Finally, the human health risk of these garden soils has been modelled by determination of health risk quotient (HRQ). As a result of our investigations, it can be claimed that mostly Cu, Zn and to a lesser degree the Ni, Cr and Pb accumulated in garden soils along roads depending on the traffic density. In general, the topsoils (0-10 cm) had higher amount of these metals rather than the subsoils (40-50 cm). Ni of these metals has approached; Cu has exceeded limit value while Pb is under it. Cd is very high in both soils along roads and control ones far from roads. Garden soils along the roads have such basic soil parameters (pH, mechanical soil type, humus content) that prove fairly high metal-binding capacity for these soils. Total risk of usage of these gardens (ingestion of soil

  4. Immobilization of heavy metals and phenol on altered bituminous coals

    SciTech Connect

    Taraba, B.; Marsalek, R.

    2007-07-01

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

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

    PubMed

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

    2015-02-01

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

  6. Heavy metal concentration and speciation in Sarcheshmeh soil, Kerman, Iran

    NASA Astrophysics Data System (ADS)

    Rastmanesh, Fatemeh; Moore, Farid

    2010-05-01

    Copper smelting in Sarcheshmeh copper complex poses a serious threat to soil contamination by toxic heavy metals (As, Cu, Mo, Cd, Pb, Zn). In this study assessment of induced pollution to soil is carried out and heavy metal speciation is investigated. Calculated geoaccumulation index (Igeo) using baseline values in control site indicate that the most polluted stations are those close to the smelter and also in the prevailing wind directions. Also the level of contamination is rapidly decreased with increasing distance from the smelter. This is in agreement with statistical results and soil pollution index (SPI) which also confirm decreasing elemental concentration with increasing distance from the smelter. Sequential extraction analyses indicate that metal mobility is not significant and the exchangeable fraction is negligible in most cases. The results of mobility factor calculation reflect decreasing heavy metal mobility with depth and also distance from the smelter. Furthermore, residual fraction constitutes a major fraction especially in the case of Pb, Mo and Zn. This may reflect contribution of native elements in topsoil enrichment, especially in areas distant from the smelter.

  7. Heavy metals in aquatic macrophytes drifting in a large river

    USGS Publications Warehouse

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

    1991-01-01

    Macrophytes drifting throughout 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 drifting 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 (range: 4000 × to 161000 ×) 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.

  8. Perspectives of plant-associated microbes in heavy metal phytoremediation.

    PubMed

    Rajkumar, M; Sandhya, S; Prasad, M N V; Freitas, H

    2012-01-01

    "Phytoremediation" know-how to do-how is rapidly expanding and is being commercialized by harnessing the phyto-microbial diversity. This technology employs biodiversity to remove/contain pollutants from the air, soil and water. In recent years, there has been a considerable knowledge explosion in understanding plant-microbes-heavy metals interactions. Novel applications of plant-associated microbes have opened up promising areas of research in the field of phytoremediation technology. Various metabolites (e.g., 1-aminocyclopropane-1-carboxylic acid deaminase, indole-3-acetic acid, siderophores, organic acids, etc.) produced by plant-associated microbes (e.g., plant growth promoting bacteria, mycorrhizae) have been proposed to be involved in many biogeochemical processes operating in the rhizosphere. The salient functions include nutrient acquisition, cell elongation, metal detoxification and alleviation of biotic/abiotic stress in plants. Rhizosphere microbes accelerate metal mobility, or immobilization. Plants and associated microbes release inorganic and organic compounds possessing acidifying, chelating and/or reductive power. These functions are implicated to play an essential role in plant metal uptake. Overall the plant-associated beneficial microbes enhance the efficiency of phytoremediation process directly by altering the metal accumulation in plant tissues and indirectly by promoting the shoot and root biomass production. The present work aims to provide a comprehensive review of some of the promising processes mediated by plant-associated microbes and to illustrate how such processes influence heavy metal uptake through various biogeochemical processes including translocation, transformation, chelation, immobilization, solubilization, precipitation, volatilization and complexation of heavy metals ultimately facilitating phytoremediation. PMID:22580219

  9. Bioremediation of toxic heavy metals using acidothermophilic autotrophes.

    PubMed

    Umrania, Valentina V

    2006-07-01

    Investigations were carried out to isolate microbial strains from soil, mud and water samples from metallurgically polluted environment for bioremediation of toxic heavy metals. As a result of primary and secondary screening various 72 acidothermophilic autotrophic microbes were isolated and adapted for metal tolerance and biosorption potentiality. The multi-metal tolerance was developed with higher gradient of concentrations of Ag, As, Bi, Cd, Cr, Co, Cu, Hg, Li, Mo, Pb, Sn and Zn. The isolates were checked for their biosolubilization ability with copper containing metal sulfide ores. In case of chalcopyrite 85.82% and in covellite as high as 97.5% copper solubilization occurred in presence of 10(-3) M multi-heavy metals on fifth day at 55 degrees C and pH 2.5. Chemical analyses were carried out by inductively coupled plasma spectroscopy (ICP) for metal absorption. The selected highly potential isolate (ATh-14) showed maximum adsorption of Ag 73%, followed by Pb 35%, Zn 34%, As 19%, Ni 15% and Cr 9% in chalcopyrite. PMID:16324838

  10. Heavy metals distribution in sediments of Nador lagoon (Morocco)

    NASA Astrophysics Data System (ADS)

    Bloundi, K.; Duplay, J.

    2003-04-01

    The Nador lagoon is a paralic system, located North-East of Morocco. At the present time this ecosystem undergoes an anthropic stress induced by urban, industrial and agricultural releases, and also by fishery activity which enriches this ecosystem in organic and inorganic wastes. A geochemical study has been undertaken, first to define the areas contaminated by heavy metals (Zn, Cu, Co, Cr and V), and second to caracterize the different mineral phases, which trap these elements. Sediment samples were collected on twenty-eight stations scattered all over the lagoon, and each core (30 cm) was subdivided in two horizons (surface and depth). Mineralogical analyses as well as major and trace elements analyses were performed on surface and deep sediments. The results on major element analyses (Si, Al, Ca, Mg, Na, P) show an enrichment in halite and phosphates in the surface sediments. This highlights on one hand, low water exchange rates between the lagoon and the Mediterranean sea, and on the other hand, an increase in organic releases related to the urban, agricultural and fishery activities. The highest concentrations in inorganic micro-pollutant were recorded N-E of the lagoon and close to Nador city. With reference to the geochemical background, it can be concluded that there is a slight contamination in heavy metals. Moreover, enrichment factor calculations (EF) for heavy metals point out an increase in metal elements as following: Zn>Co>Cr>V>Cu. Sequential extractions were performed to determine the behaviour of these micro-pollutants. Thus, it was shown that carbonates, oxides and phosphates are the preferential mineral phases for trapping these heavy metals.

  11. Plants accumulating heavy metals in the Danube River wetlands

    PubMed Central

    2013-01-01

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

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

    PubMed

    Sthiannopkao, Suthipong; Sreesai, Siranee

    2009-08-01

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

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

    PubMed Central

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

    2009-01-01

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

  14. Heavy liquid metals: Research programs at PSI

    SciTech Connect

    Takeda, Y.

    1996-06-01

    The author describes work at PSI on thermohydraulics, thermal shock, and material tests for mechnical properties. In the presentation, the focus is on two main programs. (1) SINQ LBE target: The phase II study program for SINQ is planned. A new LBE loop is being constructed. The study has the following three objectives: (a) Pump study - design work on an electromagnetic pump to be integrated into the target. (b) Heat pipe performance test - the use of heat pipes as an additional component of the target cooling system is being considered, and it may be a way to futher decouple the liquid metal and water coolant loops. (c) Mixed convection experiment - in order to find an optimal configuration of the additional flow guide for window cooling, mixed convection around the window is to be studied. The experiment will be started using water and then with LBE. (2) ESS Mercury target: For ESS target study, the following experimental studies are planned, some of which are exampled by trial experiments. (a) Flow around the window: Flow mapping around the hemi-cylindrical window will be made for optimising the flow channels and structures, (b) Geometry optimisation for minimizing a recirculation zone behind the edge of the flow separator, (c) Flow induced vibration and buckling problem for a optimised structure of the flow separator and (d) Gas-liquid two-phase flow will be studied by starting to establish the new experimental method of measuring various kinds of two-phase flow characteristics.

  15. Heavy metals leaching in Indian fly ash.

    PubMed

    Prasad, Bably; Mondal, Kajal Kumar

    2008-04-01

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

  16. Heavy Metals Contamination in Coastal Sediments of Karachi, Pakistan

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

    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

  17. Biochar Mechanisms of Heavy Metal Sorption and Potential Utility

    NASA Astrophysics Data System (ADS)

    Ippolito, J.

    2015-12-01

    Mining-affected lands are a global issue; in the USA alone there are an estimated 500,000 abandoned mines encompassing hundreds of thousands of hectares. Many of these sites generate acidic mine drainage that causes release of heavy metals, and subsequently degradation in environmental quality. Because of its potential liming characteristics, biochar may play a pivotal role as a soil amendment in future mine land reclamation. However, to date, most studies have focused on the use of biochar to sorb metals from solution. Previous studies suggest that metals are complexed by biochar surface function groups (leading to ion exchange, complexation), coordination with Pi electrons (C=C) of carbon, and precipitation of inorganic mineral phases. Several recent studies have focused on the use of biochar for amending mine land soils, showing that biochar can indeed reduce heavy metal lability, yet the mechanism(s) behind labile metal reduction have yet to be established. In a proof-of-concept study, we added lodgepole pine, tamarisk, and switchgrass biochar (0, 5, 10, 15% by weight; 500 oC) to four different western US mine land soils affected by various heavy metals (Cd, Cu, Mn, Pb, Zn). Extraction with 0.01M CaCl2 showed that increasing biochar application rate significantly decreased 'bioaccessible' metals in almost all instances. A concomitant increase in solution pH was observed, suggesting that metals may be rendered bio-inaccessible through precipitation as carbonate or (hydr)oxide phases, or sorbed onto mineral surfaces. However, this was only supposition and required further research. Thus, following the 0.01M CaCl2 extraction, biochar-soil mixtures were air-dried and metals were further extracted using the four-step BCR sequential removal procedure. Results from selective extraction suggest that, as compared to the controls, most metals in the biochar-amended mine land soils were associated with exchange sites, carbonate, and oxide phases. Biochar may play a

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

    PubMed

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

    2011-10-01

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

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

    PubMed

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

    2001-01-01

    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

  20. Heavy Metals Behavior During Thermal Plasma Vitrification Of Incineration Residues

    SciTech Connect

    Cerqueira, Nuno; Vandensteendam, Colette; Baronnet, Jean Marie

    2006-01-15

    Incineration of wastes, widely and increasingly used nowadays, produces residues, mainly bottom ash and filter fly ash. Fly ash is especially problematic because of its high content in heavy metals easily drawn out. Thermal processes, based mainly on electrical arc processes, are used to melt the residues at high temperature and convert them into a relatively inert glass. Consequently, to improve the process and get a glass satisfying regulation, control of heavy metals (lead, zinc, cadmium and chromium...) volatility during plasma fly ash melting and vitrification is needed and basic data concerning vaporization of these metals are required. According to the volatility of these compounds observed during vitrification of fly ash, a predictive model has been used to simulate the elimination of Pb, Zn and S from the melt as a function of time and temperature for a system including chlorides, oxides and sulfates. The objective of this work was the experimental study of heavy metals volatility using optical emission spectroscopy. A twin torch plasma system, mounted above a cold crucible with Ar (or Ar + O2) as plasma gas, has been used. The crucible was filled with synthetic glass in which known amounts of metallic salts were added to obtain the same chemical composition as used in the model. From spectral lines intensities of Ar, the plasma temperature profiles along the observation direction has been first established, before using ratios of spectral lines of Ar and metallic (Pb, Zn) or Cl vapors to reach the evolution of the elements concentrations above the melt. Off-gases have been analyzed by mass spectrometry. The influence of the atmosphere (Ar or Ar + O2) above the crucible has been studied and differences in elements behaviors have been pointed out. The results of the spectroscopic measurements have been compared to the ones issued of modeling, in order to validate our model of vaporization.

  1. Heavy Metals Behavior During Thermal Plasma Vitrification Of Incineration Residues

    NASA Astrophysics Data System (ADS)

    Cerqueira, Nuno; Vandensteendam, Colette; Baronnet, Jean Marie

    2006-01-01

    Incineration of wastes, widely and increasingly used nowadays, produces residues, mainly bottom ash and filter fly ash. Fly ash is especially problematic because of its high content in heavy metals easily drawn out. Thermal processes, based mainly on electrical arc processes, are used to melt the residues at high temperature and convert them into a relatively inert glass. Consequently, to improve the process and get a glass satisfying regulation, control of heavy metals (lead, zinc, cadmium and chromium…) volatility during plasma fly ash melting and vitrification is needed and basic data concerning vaporization of these metals are required. According to the volatility of these compounds observed during vitrification of fly ash, a predictive model has been used to simulate the elimination of Pb, Zn and S from the melt as a function of time and temperature for a system including chlorides, oxides and sulfates. The objective of this work was the experimental study of heavy metals volatility using optical emission spectroscopy. A twin torch plasma system, mounted above a cold crucible with Ar (or Ar + O2) as plasma gas, has been used. The crucible was filled with synthetic glass in which known amounts of metallic salts were added to obtain the same chemical composition as used in the model. From spectral lines intensities of Ar, the plasma temperature profiles along the observation direction has been first established, before using ratios of spectral lines of Ar and metallic (Pb, Zn) or Cl vapors to reach the evolution of the elements concentrations above the melt. Off-gases have been analyzed by mass spectrometry. The influence of the atmosphere (Ar or Ar + O2) above the crucible has been studied and differences in elements behaviors have been pointed out. The results of the spectroscopic measurements have been compared to the ones issued of modeling, in order to validate our model of vaporization.

  2. Contribution of the arbuscular mycorrhizal symbiosis to heavy metal phytoremediation.

    PubMed

    Göhre, Vera; Paszkowski, Uta

    2006-05-01

    High concentrations of heavy metals (HM) in the soil have detrimental effects on ecosystems and are a risk to human health as they can enter the food chain via agricultural products or contaminated drinking water. Phytoremediation, a sustainable and inexpensive technology based on the removal of pollutants from the environment by plants, is becoming an increasingly important objective in plant research. However, as phytoremediation is a slow process, improvement of efficiency and thus increased stabilization or removal of HMs from soils is an important goal. Arbuscular mycorrhizal (AM) fungi provide an attractive system to advance plant-based environmental clean-up. During symbiotic interaction the hyphal network functionally extends the root system of their hosts. Thus, plants in symbiosis with AM fungi have the potential to take up HM from an enlarged soil volume. In this review, we summarize current knowledge about the contribution of the AM symbiosis to phytoremediation of heavy metals. PMID:16555102

  3. Constraints in cropping heavy-metal contaminated fluvial sediments.

    PubMed

    Smilde, K W; van Driel, W; van Luit, B

    1982-11-01

    Growth and heavy-metal uptake of various food crops and grass cultivated on harbour dredge spoils were studied, and health aspects in consuming the marketable products were discussed. Vegetables (potato, carrot, radish, endive, lettuce) and grass (English ryegrass) performed well on dredge spoils, but small grains (wheat, barley) were affected by manganese deficiency. As compared with crops grown on uncontaminated reference soils, there was a net accumulation of As and heavy metals, especially so Cd, Zn and Cu, and a reduced uptake of Mn. Mainly because of the elevated Cd concentrations of the edible parts, exceeding the guideline of 0.1 mg/kg in fresh matter, the harbour dredge spoils investigated are considered unfit for the production of food crops, but may be used as grassland for dairy cattle. Highest Cd concentrations were attained in leafy vegetables and wheat (grain) and lowest in potato (tuber). PMID:7156971

  4. [The biochemical carcinogenesis of selected heavy metals in bladder cancer].

    PubMed

    Rorbach-Dolata, Anna; Marchewka, Zofia; Piwowar, Agnieszka

    2015-01-01

    Bladder cancer takes the second place in the classification of morbidity of urinary system cancers. Many chemical factors take part in cancerogenesis. It is suggested that exposure to heavy metals such as arsenic, chromium, nickel and cadmium as well as its metabolites may trigger the bladder cancer through inducing excessive reactive oxygen species production and oxidative stress formation which are responsible for DNA damage. In patients with bladder cancer is observed the disorder of processes regulated by p-53, including apoptosis. There are many patients with bladder cancer with confirmed absence of retinoblastoma protein, which is responsible of holding on the process of coming up the cells with mutation into synthesis, where the replication process undergoes. It is mentioned that excessive expression of proto-oncogenes may also cause the bladder cancer. The article concerns biochemical effects of exposure to chosen heavy metals and their potential role in bladder cancer progression. PMID:26689010

  5. Situ formation of apatite for sequestering radionuclides and heavy metals

    DOEpatents

    Moore, Robert C.

    2003-07-15

    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.

  6. Sublethal Heavy Metal Stress Stimulates Innate Immunity in Tomato

    PubMed Central

    Chandra, Swarnendu; Acharya, Krishnendu

    2015-01-01

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

  7. Wetland plants as indicators of heavy metal contamination.

    PubMed

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

    2015-03-15

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

  8. Heavy metal transport in the hindon river basin, India.

    PubMed

    Jain, C K; Sharma, M K

    2006-01-01

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

  9. Heavy Metal Bioabsorption Capacity of Intestinal Helminths in Urban Rats

    PubMed Central

    TEIMOORI, Salma; SABOUR YARAGHI, Aliakbar; MAKKI, Mahsa Sadat; SHAHBAZI, Farideh; NAZMARA, Shahrokh; ROKNI, Mohhamad Bagher; MESDAGHINIA, Alireza; SALAHI MOGHADDAM, Abdoreza; HOSSEINI, Mostafa; RAKHSHANPOUR, Arash; MOWLAVI, Gholamreza

    2014-01-01

    Abstract Background The aim of the present study was to evaluate the capability of helminths to absorb heavy metals in comparison with that of the host tissues. Methods We compared the concentration of cadmium (Cd) and chromium (Cr) in urban rats and in their harboring helminthes —Moniliformis moniliformis, Hymenolepis diminuta and larval stage of Taenia taenaeiformis (Cysticercus fasciolaris). The heavy metal absorption was evaluated in 1g wet weight of parasites and tissues digested in nitric acid, using Inductivity Coupled Plasma (ICP_OES). Results A higher concentration of heavy metals was revealed in the helminths than in the host tissues. Bioconcentration factor (BF= C in parasite/C in tissue) for both Cd and Cr absorption was more than 10-fold higher in M. moniliformis than in the three compared host tissues. The BF of Cd in M. moniliformis compared to the liver, kidney and muscle of the host was 9.16, 14.14 and 17.09, respectively. BF in Cr in the same parasite and the same host tissues ranged from 10.67, 7.06 and 4.6. High level of absorption in H. diminuta was significantly likewise; the individual BF of Cd and Cr in H. diminuta compared to the liver, kidney and muscle of the hosts was 4.95, 5.94 and 4.67 vs. 2.67, 11.56 and 5.59. The mean concentration of Cd and Cr in C. fasciolaris was also significantly higher than that in the rat livers (P<0.007 and P<0.004, respectively). Conclusion This study claims that parasites of terrestrial animals exposed to heavy metals can be more accurate indicators than the host tissues as new environmental monitoring agents. PMID:25988090

  10. Effects of Gravity on Processing Heavy Metal Fluoride Fibers

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

    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.