Sample records for heavy metals speciation

  1. Speciation of heavy metals in River Rhine

    NARCIS (Netherlands)

    Vega, F.A.; Weng, L.


    Chemical speciation of Zn, Cu, Ni, Cd and Pb in River Rhine was studied by measuring free ion concentration and distribution in nanoparticles, and by comparing the measurement with speciation modeling. Concentrations of free metal ions were determined in situ using Donnan Membrane Technique (DMT).

  2. Fractionation, characterization and speciation of heavy metals in ...

    African Journals Online (AJOL)

    Speciation of heavy metals in soils determines the availability for metals for plant uptake and potential for contamination of groundwater following application of composts to agricultural lands. Methods used to characterize heavy metals in solid phase of composts and compost amended soils include physical fractionation ...

  3. Speciation of Heavy Metals in Sediment of Agbabu Bitumen deposit ...

    African Journals Online (AJOL)

    Speciation of heavy metals Cu, Cd, Pb, Ni, Zn, Mn, Fe, Cr and Hg was carried out on sediment of Agbabu with a sequential extraction procedure in the dry and rainy seasons of year 2008. Hg was not detected in all the fractions in the two seasons. In the dry season, all the metals were mostly abundant in Fraction-5, however ...

  4. Heavy metal speciation and their accumulation in sediments of Lake ...

    African Journals Online (AJOL)

    Several sediment samples in Lake Burullus have been affected by the discharges of heavy metals through different drains. The study aimed to analyze the chemical speciation of these metals. In particular, the chemical forms of Cd, Cu, Fe, Mn, Pb and Zn in sediments collected in spring season were studied using a ...

  5. speciation of heavy metals in street dust samples from sakarya

    African Journals Online (AJOL)

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    SPECIATION OF HEAVY METALS IN STREET DUST SAMPLES FROM SAKARYA. I. ORGANIZED INDUSTRIAL DISTRICT USING THE BCR SEQUENTIAL. EXTRACTION PROCEDURE BY ICP-OES. Nilufer Ozcan and Huseyin Altundag*. Sakarya University, Faculty of Arts and Sciences, Department of Chemistry, 54187, ...

  6. Investigation on speciation and pollution index of heavy metals in ...

    African Journals Online (AJOL)

    This study investigated the chemical speciation of Cd, Cr, Cu, Ni and Pb and their contamination/pollution indices in the sediment of River Ala in Akure, Nigeria. Sediment samples taken along the course of the river were subjected to Sequential Extraction Technique and the heavy metals were quantified using atomic ...

  7. Speciation of Heavy Metals in Sediment of Agbabu Bitumen deposit ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: Speciation of heavy metals Cu, Cd, Pb, Ni, Zn, Mn, Fe, Cr and Hg was carried out on sediment of. Agbabu with a sequential .... sulphide:The residue from fraction 3 was oxidized as follows: 3ml of 0.02M HNO3 and 5ml of ... Another 3ml of 30% hydrogen peroxide, adjusted to. pH2 with HNO3, was then added.

  8. Heavy metal speciation and toxicity characteristics of tannery sludge (United States)

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


    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.

  9. Electrodialytic removal of heavy metals from different fly ashes. Influence of heavy metal speciation in the ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne


    in lab scale, and the results were discussed in relation to the expected heavy metal speciation in the ashes. In initial leaching experiments the pH-dependent desorption characteristics of the heavy metals Cd, Pb, Zn and Cu were analogous in the two MSWI ashes, and thus it was expected...... that the speciation of these metals was similar in the two ashes. On the other hand, the leaching behaviour (and concentration) of Cr was diverse. The apparent similar speciation of Cd, Pb, Zn and Cu was only partly confirmed in the following electrodialytic remediation experiments. Significant differences in re......Electrodialytic Remediation has recently been suggested as a potential method for removal of heavy metals from fly ashes. In this work electrodialytic remediation of three different fly ashes, i.e. two municipal solid waste incinerator (MSWI) fly ashes and one wood combustion fly ash was studied...

  10. The influence of speciation on the ecotoxic effects of heavy metals in aquatic systems

    DEFF Research Database (Denmark)

    Jensen, Karen S.; Borggaard, Ole K.; Hauschild, Michael Zwicky

    The fate, bioavailability and exposure of aquatic organisms to potentially toxic metals are strongly influenced by the speciation of the metal ions in the medium. Metal speciation is mainly controlled by pH, ionic strength, and presence of ligands ranging from small ions (e.g. citrate, EDTA...... for the total chemical mass emitted into the environment. In this study we show that by means of the metal speciation, EF can be corrected in such a way that the resulting CF becomes more accurate for each metal in the LCIA. The chemical speciation in various media was calculated by Visual Minteq ver. 2.......56. Calculations showed that the speciation is very dependent on the metal concentration and the composition of the media. A large variation in heavy metal toxicity for the same test organism was found for a given metal in different media. Our main hypothesis is that this is due to differences in speciation...

  11. Speciation of Heavy Metals in Sediment of Agbabu Bitumen deposit ...

    African Journals Online (AJOL)

    Michael Horsfall

    soils and water from the vicinity of Agbabu bitumen field (Olajire et al., 2007), and solvent extraction of vanadium from Nigerian bitumen (Oguntimehin and. Ipinmoroti, 2007). The need for this research arose because no study has been reported on the speciation of metals in sediment of Agbabu bitumen deposit environment ...

  12. Interpretation of heavy metal speciation in sequential extraction using geochemical modelling

    NARCIS (Netherlands)

    Cui, Yanshan; Weng, Liping


    Environmental context Heavy metal pollution is a worldwide environmental concern, and the risk depends not only on their total concentration, but also on their chemical speciation. Based on state-of-the-art geochemical modelling, we pinpoint the heavy metal pools approached by the widely used

  13. Chemical speciation of heavy metals in sandy soils in relation to availability and mobility

    NARCIS (Netherlands)

    Temminghoff, E.J.M.


    The environmental risk of heavy metals which are present in soil at a certain total content is highly dependent on soil properties. Chemical speciation is a comprehensive term for the distribution of heavy metals over all possible chemical forms (species) in soil solution and in the solid

  14. Speciation of heavy metal ions as influenced by interactions with montmorillonite, Al hydroxide polymers and citrate

    NARCIS (Netherlands)

    Janssen, R.P.T.


    Clay minerals, metal-hydroxides and organic matter can bind metal ions; moreover they also interact with each other. These mutual interactions influence the metal binding to a significant extent. In this study, the speciation of the heavy metal ions Zn and Ph was investigated in model

  15. Speciation of heavy metals in inter—tidal sediments of Okrika river

    African Journals Online (AJOL)

    ABSTRACT. The species and total metal concentrations of some environmentally toxic metals in inter-tidal sediments of the Okrika river system was examined. The determination of the heavy metal loadings, speciation patterns and other chemical parameters has revealed some. significant correlation in inter-tidal sediments ...


    Directory of Open Access Journals (Sweden)

    Chiara Ferronato


    Full Text Available The objective of the study was to understand the equilibrium relationship between the heavy metals concentrations in superficial water and pore water. At  water-sediment interface, the equilibrium rapidly changed and it is influenced by chemico-physical parameters of aquatic ecosystems. The hydraulic safety of Bologna plain (North Italy depends on network of artificial canals and they are related with natural rivers of Reno basin (Reno river and its tributaries. The natural and artificial water courses flowed in agricultural, urban and industrial land. The heavy metals concentration in water and sediment discriminated the human pressure on the land and their spatial distribution in sediment could predict the hazard of pollution in aquatic ecosystems. We compared the heavy metals concentrations in pore water and superficial water determined in natural rivers and artificial canals, and more pollution in artificial canals than natural rivers was found. Furthermore, the coefficient of partition (log Kd between water and sediments was calculated to evaluate the bioavailability of heavy metals adsorbed on the sediments. The heavy metals extracted in deionised water at equilibrium after 16 h showed higher concentrations than those determined directly on water samples.

  17. speciation of heavy metals in the sidments of gubi dam, bauchi state ...

    African Journals Online (AJOL)


    have always focused on point source pollution with much attention being paid to ... and Zn at industrial and non-industrial areas. (Saenz et al., 2005). ... (v/v). The heavy metal concentrations in the digest were determined a Buck Scientific Model. GP. 210 using. Atomic. Absorption. Spectrophotometer (AAS). Metal Speciation.

  18. Heavy Metals Speciation in Dust Samples from Various Parts of ...

    African Journals Online (AJOL)

    Dust samples were collected using 1m2 HDPE containers, oven dried at 70OC and sieved through 100ìm nylon sieve. 1g of each sample was digested using HCl/HNO3/H2O2 acid mixture and the concentration levels of 8 selected metals were measured using ICP-MS. Average concentrations of heavy metals in dust ...

  19. Selected heavy metals speciation in chemically stabilised sewage sludge (United States)

    Wiśniowska, Ewa; Włodarczyk-Makuła, Marła


    Selected heavy metals (Pb, Ni, Cd) were analysed in soil, digested sewage sludge as well as in the sludge stabilised with CaO or Fenton's reagent. The dose of Fenton's reagent was as follows: Fe2+ = 1g.L-1, Fe2+/H2O2=1:100; stabilisation lasted for 2 h. Dose of CaO was equal to 1 g CaO.g d.m.-1 Total concentration of all metals in the digested sewage sludge was higher than in the soil. Chemical stabilisation of sludge with Fenton's reagent increased total metal content in the sludge as a result of total solids removal. Opposite effect was stated when the sludge was mixed with CaO. Also chemical fractions of heavy metals were identified (exchangeable, carbonate bound, iron oxides bound, organic and residual). The results indicate that stabilisation of the sludge with Fenton's reagent increased mobility of heavy metals compared to the digested sludge. Amendment of CaO increased percent share of examined metals in residual fraction, thus immobilised them and decreased their bioavailability.

  20. Chemical Speciation and Mobility of Some Heavy Metals in Soils ...

    African Journals Online (AJOL)

    The mobility of some heavy metals (Fe, Co, Ni and Mn) in soils around automobile waste dumpsites in Northern part of Niger Delta was assessed using Tessier et al. five syteps sequential chemical extraction procedure. The results showed that majority of iron and manganese were associated with the residual fraction with ...

  1. Speciation of heavy metals in paddy soils from selected areas in ...

    African Journals Online (AJOL)

    The speciation of heavy metals in paddy soils was determined in order to gain insight regarding their origin and distribution in soils. Five sampling ... This study shows that the soil samples were clayey (82 to 96% of grain size <63 μm), fairly high in organic carbon (6.54 to 8.71%) and slightly acidic (pH 4.92 to 5.12). Heavy ...

  2. Variation of heavy metal speciation during the pyrolysis of sediment collected from the Dianchi Lake, China

    Directory of Open Access Journals (Sweden)

    Zhenggang Gu


    Full Text Available Sediment samples with high organic carbon were collected from the Dianchi Lake in China and thermally treated using a method analogous to biochar production. The speciation of the heavy metals Cu, Cd, Pb, and Zn in sediment and thermally treated sediments (TTSs were analyzed by European Community Bureau of Reference (BCR sequential extraction methods. Heavy metal bioavailability and eco-toxicity were assessed by risk assessment code. This study demonstrates that BCR sequential extraction methods and risk assessment code can be used as valuable tools to assess heavy metal mobility, bioavailability and eco-toxicity. Compared to biochar derived from biomass, TTSs had different characteristics, which may contribute to the formation of organo-mineral complexes. The heavy metals Cu, Cd, Pb, and Zn speciated in TTSs show different patterns from that of the sediment and pyrolysis temperature has a great influence on the fractional distribution of heavy metals. Those different distributions may attribute to the geochemistry of the sediment and the different physicochemical characteristics of heavy metals. In order for the safe application of thermally –treatment sediments (TTSs as a soil amendment, further studies such as field experiments may be required.

  3. Sources and speciation of heavy metals in municipal solid waste (MSW) and its effect on the separation technique

    Energy Technology Data Exchange (ETDEWEB)

    Biollaz, S.; Ludwig, Ch.; Stucki, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)


    A literature search was carried out to determine sources and speciation of heavy metals in MSW. A combination of thermal and mechanical separation techniques is necessary to achieve the required high degrees of metal separation. Metallic goods should be separated mechanically, chemically bound heavy metals by a thermal process. (author) 1 fig., 1 tab., 6 refs.


    Directory of Open Access Journals (Sweden)

    Constantin Luca


    Full Text Available In this work we present the results of a methodological research on the chemical speciation of heavy metals found in surface waters of an area polluted by mining activities (in the Western Carpathians. The surface water samples were collected in two seasons (summer and fall. Each time were performed in situ physical-chemical measurements (pH, Eh, conductivity, temperature and analytical determination of total concentrations of some metals (manganese, copper, zinc, iron, cadmium and anions (SO42-, Cl-, PO43-, NO3-. Analyze of chemical speciation of these metals was made using the PHREEQC program which allowed us to determine the distribution of studied elements. The concordance of the results obtained with this program with thermodynamic predictions arising from potential - pH equilibrium diagrams - Pourbaix type justify the compatibility between the program calculation and experimental data.

  5. Selective Separation and Determination of Heavy Metals (Cd, Pb, Cr) Speciation Forms from Hortic Antrosols (United States)

    Bulgariu, D.; Bulgariu, L.


    The speciation, inter-phases distribution and biodisponibility of heavy metals in soils represent one of main problem of environmental geochemistry and agro-chemistry. This problem is very important in case of hortic antrosols (soils from glasshouses) for the elimination of agricultural products (fruits, vegetables) contamination with heavy metals. In soils from glass houses, the speciation and inter-phases distribution processes of heavy metals have a particular dynamic, different in comparison with those from non-protected soils. The predominant distribution forms of heavy metals in such soils types are: complexes with low mass organic molecules, organic-mineral complexes, complexes with inorganic ligands (hydroxide-complexes, carbonate-complexes, sulphate-complexes, etc.) and basic salts. All of these have high stabilities in conditions of soils from glass houses, and in consequence, the separation and determination of speciation forms (which is directly connected with biodisponibility of heavy metals) by usual methods id very difficult and has a high uncertain degree. In this study is presented an original method for the selective separation and differentiation of speciation forms of heavy metals from glass houses soils, which is based by the combination of solid-liquid sequential extraction (SPE) with the extraction in aqueous polymer-inorganic salt two-phase systems (ABS). The soil samples used for this study have been sampled from three different locations (glass houses from Iasi, Barlad and Bacau - Romania) where the vegetables cultivation have bee performed by three different technologies. In this way was estimated the applicability and the analytical limits of method proposed by as, in function of the chemical-mineralogical and physical-chemical characteristics of soils. As heavy metals have been studied cadmium, lead and chromium, all being known for their high toxicity. The procedure used for the selective separation and differentiation of speciation

  6. speciation of heavy metals in street dust samples from sakarya

    African Journals Online (AJOL)

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    results was checked by analysis of the BCR-701 certified reference material. The concentrations of metals ... All laboratory glassware and plastic ware were rinsed five times with distilled deionized Ultra High .... The total metal analysis was performed with 0.5 and 1.0 g of dust samples using aqua regia as digestion solution.

  7. Speciation and mobility of volatile heavy metals (Cd, Pb, and Tl) in fly ashes. (United States)

    Świetlik, Ryszard; Trojanowska, Marzena; Karbowska, Bożena; Zembrzuski, Włodzimierz


    Speciation of volatile metals Cd, Pb, and Tl in fly ashes (FAs) produced from burning of hard coal in stocker-fired boilers (SFBs) was studied. Two grain fractions of fly ash collected in a multicyclone and battery cyclone of the systems of dust separation from three SFB units operating in various urban heating plants were analyzed. The characteristic feature of speciation of the three metals was a large share of labile fractions: Cd (av. 46.1 %), Pb (av. 39.8 %), and Tl (av. 21.6 %). The fraction which most clearly reflected the different chemical properties of the investigated metals was the oxidizable fraction: F(4)-Cd-0 %, F(4)-Pb-av. 10.0 %, and F(4)-Tl-av. 30.2 %. The importance of condensation of the volatile metal species on FA particles for shaping speciation of these metals was characterized using the normalized enrichment factor (NEF): Pb (2.3 ± 0.8) > Tl (1.8 ± 0.9) ≈ Cd (1.7 ± 0.6). Speciation of heavy metals may also be important economically, because the level of mobility coefficients (K Cd = 0.46, K Pb = 0.40, and K Tl = 0.22) in the case of fly ashes considerably enriched with toxic metals (Cd 4.8 ± 3.4 mg/kg, Pb 293 ± 210 mg/kg, and Tl 6.3 ± 4.5 mg/kg) may limit their utilization range.

  8. Speciation of Aquatic Heavy Metals in Humic Substances by$^{111m}$Cd/$^{199m}$Hg-TDPAC

    CERN Multimedia


    Humic substances are ubiquitous in waters and soils and act as complexing agents for different heavy metals, e.g. Cd, Hg. Toxicity, reactivity, fixation and migration are therefore strongly influenced by the interactions between heavy metals and humic substances. Humic substances derive from postmortal materials such as rotten plants, have dark colours and usually a molecular weight between 500 and 10~000 Dalton. Complex formation studies with different heavy metal ions indicate at least two different kinds of metal sites. Usually, these studies are restricted to heavy metal concentrations 2 to 3 orders of magnitude higher than the natural heavy metal abundance (i.e. 10$^{-10}$ molar). This serious limitation can be overcome by the use of suitable radiosotope techniques capable of metal speciation at extreme sensitivity levels such as TDPAC (Time Differential Perturbed Angular Correlation of~$\\gamma$-rays). Thus, we studied the interaction of heavy metals with humic substances by monitoring the nuclear quadru...

  9. Heavy metal speciation and risk assessment in dry land and paddy soils near mining areas at Southern China. (United States)

    Liu, Guannan; Wang, Juan; Zhang, Erxi; Hou, Jing; Liu, Xinhui


    Heavy metal contamination of soils has been a long-standing environmental problem in many parts of the world, and poses enormous threats to ecosystem and human health. Speciation of heavy metals in soils is crucial to assessing environmental risks from contaminated soils. In this study, total concentrations and speciation of As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn were measured for agricultural soils near mines along the Diaojiang River in Guangxi Zhuang Autonomy Region, China. The sources of heavy metals in soils also were identified to assess their effect on speciation distribution of soil heavy metals. Furthermore, the speciation distribution of Cd and Zn, main soil heavy metal pollutants, in dry land and paddy soils were compared. Results showed that there were two severely polluted regions near mine area reaching alarming pollution level. As, Cd, Pb, and Zn were more affected by mining activities, showing very strong pollution level in soils. The mean percentage of exchangeable and carbonate fraction was highest and up to 46.8 % for Cd, indicating a high environmental risk. Greater bioavailable fractions of As, Cd, Cu, Mn, Pb, and Zn were found in soils heavily polluted by mining activities, whereas Cr and Ni as geogenic elements in the stable residual fraction. In addition, in the dry land soils, reducible fraction proportion of Cd was higher than that in the paddy soils, whereas exchangeable and carbonate fraction of Cd was lower than that in the paddy soils. Oxidizable fraction of Zn was higher in the paddy soils than that in the dry land soils. The results indicate that the sources of soil heavy metals and land types affect heavy metal speciation in the soil and are significant for environmental risk assessment of soil heavy metal pollutions.

  10. Chemical speciation and bioavailability of heavy metals in soil and surface water

    NARCIS (Netherlands)

    Kalis, E.J.J.


    Keywords:Metal speciation, Bioavailability, Lolium perenne , Free metal ion, Donnan Membrane Technique, Humic acid, Metal uptake, Speciation techniques, Competition, Soil (solution)

  11. Speciation of heavy metals in coastal water of Qeshm Island in the Persian Gulf

    Directory of Open Access Journals (Sweden)

    A.R. Karbassi


    Full Text Available Fuel storage tanks are one of the main sources of water pollution as well as loss of crude oil and oil products in refineries.  In the process of utilization of these tanks, considerable amounts of hydrocarbons may find their way into the coastal water, which eventually lead to loss of valuable hydrocarbons. Oil type, climatic condition and characteristics of oil tanks are among the main variables in computing evaporative losses. The present study brings out the results of a project that was carried out to investigate the adverse effects of oil terminal on coastal waters of Qeshm Island and aims to elaborate on speciation of metals in coastal waters. For this purpose, 12 stations were sampled. Water chemistry software was used to draw Eh-pH diagrams. Along with the speciation of heavy metals, cluster analysis was carried out by MVSP software. According to the results, HSC diagrams showed that Cu and Cd were present as free ions. Lead, manganese, cobalt, zinc and nickel were respectively present as PbOH, MnOH, ZnOH, CoOH and NiOH in the Persian Gulf. Speciation of Cu and Ni was in the form of Cu2O and NiO. Vanadium was also present in combination with hydroxide. Since all the studied elements were within the water stability range, they were stable, and there were no environmental risks of contamination and toxicity. The results of cluster analysis did not show any relation between Eh and pH. This clearly showed that Eh-pH was governed by different mechanisms in coastal waters of Qeshm Island. Vanadium and Ni concentration was governed by pH, while Cu and Cd concentration was controlled by Eh.

  12. [Effect of Nano-TiO₂ on Release and Speciation Changes of Heavy Metals in Soil]. (United States)

    Zhang, Jin-yang; Wang, Ding-yong; Liang, Li; Li, Chu-xian; Zhang, Cheng; Zhou, Xiong; Liu, Juan


    The effects of nano-TiO₂ on migration and transformation of heavy metals in soil were investigated by outdoor flooding simulation experiments. Cr, Pb, Zn, Cd and Cu contents of different forms were determined in soil of typical fluctuating zone of Three Gorges Reservoir. The results showed that, after flooding months, both addition of 4 g · kg⁻¹ of rutile and anatase particles resulted in the release of about 30% Cr into the water. Nano-TiO₂ particles mainly promoted the dissolution of oxidizable residual Cr, and elevated its ecological risk. Thus nano-TiO₂promoted the activation of chromium and improved the mobility of chromium in soil. 4 g · kg⁻¹ of rutile particles caused the decrease of acid exchangeable lead by 25.92% and oxidizable lead by 33.09%, and enhanced the mobility of Pb. However, anatase particles caused the increase of oxidizable zinc by 30% in soil, which facilitated fixing of zinc. In addition, two types of nano-TiO₂particles had no significant effect on the speciation changes of Cu and Cd. Therefore, the effect of nano-TiO₂ on release and transformation of Cr in soil was the largest, followed by Pb and Zn. This needs special attention when using nano-TiO₂ to remediate heavy metals contaminated soil and assessing its environmental risk.

  13. Electrochemical metal speciation in colloidal dispersions


    Wonders, J.H.A.M.


    The term "heavy metals" is connected with toxicity. They form strong complexes with enzymes, other proteins and DNA in living organisms, which causes dysfunctioning and hence poisoning. In combination with the uptake mechanism of the organism, speciation of heavy metal determines the bio-availability of heavy metals. In the environment, heavy metals are complexed by soil particles or molecules of organic and inorganic origin. This thesis deals with the speciation and the binding char...

  14. [Chemical speciation and risk assessment of heavy metals in the middle part of Yarlung Zangbo surface sediments]. (United States)

    Bai, Jian-kunt; Li, Chao-liu; Kang, Shi-chang; Chen, Peng-fei; Wang, Jian-li


    Nine heavy metals (Cd, Co, Ni, Cu, Zn, Pb, Cs, As, Cr) of surface sediments collected from the Middle Part of the Yarlung Zangbo River were analyzed by BCR sequential extraction procedure. Based on speciation distributions of these metals, ecological risk of heavy metals was assessed with methods of risk assessment code (RAC) and sediment quality guideline quotient (SQG-Q). The results show that: (1) Large part of Cr and As belong to residual fraction(87%-96%). Ni, Cu, Co and Cs have similar distribution characteristics (non-residual part accounts for approximate 20%). Correspondingly, mass fraction of Cd exists mainly in acid soluble and reducible faction (65% ) , indicating high ecological risk level. (2) Based on calculation of RAC method, Cd is of high risk to the environment (37. 38%). Accordingly, Co, Ni, Cu and Zn are of low risk, and Pb, Cs, As and Cr pose extreme low risk to the environment. According to evaluation of heavy metal speciation distributions, the potential ecological risk of heavy metals is in the descending order of Cd > Co > Ni > Cu > Zn > Pb > Cs > As > Cr. (3) The SQG index of sediments is 0. 804, indicating that studied river sediment has a moderate potential biological toxicity effect. Given most of heavy metals exists in residual fraction, the sediments of this region pose a low ecological risk to the environment.

  15. Geochemical speciation and pollution assessment of heavy metals in surface sediments from Nansi Lake, China. (United States)

    Yang, Liyuan; Wang, Longfeng; Wang, Yunqian; Zhang, Wei


    Sixteen surface sediment samples were collected from Nansi Lake to analyze geochemical speciation of heavy metals including Cd, As, Pb, Cr, and Zn, assess their pollution level, and determine the spatial distribution of the non-residual fraction. Results showed that Cd had higher concentrations in water-soluble and exchangeable fractions. As and Pb were mainly observed as humic acid and reducible fractions among the non-residual fractions, while Cr and Zn were mostly locked up in a residual fraction. The mean pollution index (P i) values revealed that the lower lake generally had a higher enrichment degree than the upper lake. Cd (2.73) and As (2.05) were in moderate level of pollution, while the pollution of Pb (1.80), Cr (1.27), and Zn (1.02) appeared at low-level pollution. The calculated pollution load index (PLI) suggested the upper lake suffered from borderline moderate pollution, while the lower lake showed moderate to heavy pollution. Spatial principle component analysis showed that the first principal component (PC1) including Cd, As, and Pb could explain 56.18 % of the non-residual fraction. High values of PC1 were observed mostly in the southern part of Weishan Lake, which indicated greater bioavailability and toxicity of Cd, As, and Pb in this area.

  16. Use of Innovative and Advanced Computer Simulations of Chemical Speciation of Heavy Metals in Soils and Other Environmental Samples

    Directory of Open Access Journals (Sweden)

    Jeske Agnieszka


    Full Text Available The article presents several aspects of computer simulations and models of heavy metals speciation in environmental samples. The methods can be effectively used in environmental sciences, soil science, and assessment of mobility and bioavailability of heavy metals in contaminated areas. The article presents all of the methods based on examples, and with interpretation of results. The effect depends on the reliability of data used in models. The results are essential for predicting the fate and behaviour of elements in the environment, and can also be used to develop solubility curves.

  17. Preliminary study on heavy metals contamination of soil using solid phase speciation and the influence on groundwater in Bozanta-Baia Mare Area, Romania

    National Research Council Canada - National Science Library

    Frentiu, Tiberiu; Ponta, Michaela; Levei, Erika; Gheorghiu, Emilia; Benea, Marcel; Cordos, Emil


    A preliminary study on soil contamination with heavy metals and As based on solid phase speciation according to the Tessier scheme and the influence on groundwater in an area under anthropogenic influence...

  18. [Speciation and Risk Assessment of Heavy Metals in Surface Sediments from the Heavily Polluted Area of Xiaoqing River]. (United States)

    Huang, Ying; Li, Yong-xia; Gao, Fu-wei; Xu, Min-min; Sun, Bo; Wang, Ning; Yang, Jian


    Th concentrations of Cu, As, Pb, Zn, Cr, Cd, Ni in interstitial water were analyzed by ICP-MS from the heavily polluted area of Xiaoqing River. A modified BCR's sequential extraction procedure was used to investigate the fraction of the heavy metals in the surface sediments. The aquatic toxicity of heavy metals in interstitial water was assessed by US Water Quality Criteria (CCC, CMC). Based on the speciation of the metals in the surface sediments, the ecological risk of heavy metals was assessed with methods of risk assessment code (RAC) and potential ecological risk index. The results showed that: The tested heavy metals would not pose chronic toxicity for aquatic ecosystem. The contents of heavy metals (Cu, Pb, Zn, Cr, Cd, Ni) in the surface sediments were higher than the background values of the local soils, indicating enrichment of heavy metals. Cu, As and Ni were mainly composed with residual fractions, Pb and Cr were mainly constituted of residual and oxidizable fractions, and mass fractions of Zn and Cd existed mainly in acid soluble and reducible factions. The contents of bio-available fractions of Cd, Zn, Cr and Pb in the sediments were higher those of residual fractions, indicating high potential for secondary release. Based on calculation of RAC method, Cu, Pb, Cr and As posed extremely low to low risk to the environment. Accordingly, Ni was of low to medium risk, Cd was of medium to high risk, and Zn was of medium to extremely high risk to the environment. The potential ecological risk of heavy metals in the sediments was in the descending order of Cd > Zn > Ni > As > Cu > Cr > Pb. Cd had high to very high potential ecological risk comparing with the other heavy metals. The potential ecological risk indexes (RI) of the heavy metals in the sediments were in the range of 136.83-264.83, and posed medium to high potential ecological risks for Xiaoqing River.

  19. Hydrochemical processes in mine waste deposits and drainage water - Heavy metal speciation, sorption and sedimentation processes

    Energy Technology Data Exchange (ETDEWEB)

    Loevgren, L.; Sjoeberg, S. [Umeaa Univ. (Sweden). Dept. of Inorganic Chemistry


    The aim of the present project has been to quantitatively describe hydrochemical processes relevant for the retention and mobility of heavy metals in mine waste deposits. The activities have been focused on the solubility and speciation of Pb(II), Cd(II), Cu(II), Zn(II), CR(VI) and As(III,V). Main attention has been paid to adsorption processes at the surfaces of iron (hydr)oxides (goethite, et-FeOOH). The main experimental methods for studying the adsorption reactions have been potentiometric titrations and batch adsorption experiments. Experimental data have been evaluated in terms of models for surface complexation equilibria, which can be used in hydrogeochemical model calculations of processes within the deposits as well as in the recipients of drainage water. Furthermore, in several cases the surface complexes formed have been characterized structurally by means of Fourier Transform-Infrared spectroscopy. In order to test the validity of the equilibrium models obtained at millimolar concentrations of both sorbate and sorbent a new method utilizing Anodic Stripping Voltammetry as an in situ probe in titrations has been developed within the project. A particular interest has been given to the influence of complexing inorganic and organic anions on the adsorption of the heavy metal ions. The presence of sulfate ions resulted in a moderate increased adsorption of Cu(II) and Pb(II) under acidic conditions, while the adsorption of Zn(II) remained uninfluenced. The increased adsorption could be explained by reduced electrostatic repulsion between positively charged surfaces and metal ions, and by formation of ternary surface complexes. Similar mechanisms could explain the data in the goethite-Me(II)- carboxylate systems. The organic acids study are: phthalic acid, trimellitic acid and pyromellitic acid, which are aromatic acids with two, three and four carboxylate groups, respectively. Before the experimental data in the organic containing systems could be

  20. Speciation study of the heavy metals in commercially available recharge cards coatings in Nigeria and the health implication

    Directory of Open Access Journals (Sweden)

    Abolanle S. Adekunle


    Full Text Available This work assessed levels of heavy metals exposure from silver coatings of mobile phones recharge cards of three major companies (designated as A, B and C with price denominations 100, 200 and 400 from companies A, B and C respectively, which were carefully scratched using a plastic scraper into a glass tube. The coatings were acid digested for total metal concentration, while speciation experiment for Mn, Cu, Cd and Pb was carried out. Total metals and speciation analysis were done using AAS and XRF techniques. The total metal concentration from XRF analysis was in the range: Ca (70–2140 μg/g, K (20–4930 μg/g, Sc (80–270 μg/g, Ti (1530–12,580 μg/g, Fe (50–6660 μg/g, Ni (20–2040 μg/g, Cu (20–850 μg/g and Zn (40–460 μg/g. Cr had the lowest concentration (10 μg/g in A (400 while Ti had the highest concentration (12,580 μg/g in C (500 for all the coatings analyzed. AAS and XRF results agreed closely except for Fe with higher concentration. A (100 contained high concentration of the metals compared with others. Speciation study identified Mn as the most mobile element when present in the environment.

  1. Heavy metal removal and speciation transformation through the calcination treatment of phosphorus-enriched sewage sludge ash. (United States)

    Li, Rundong; Zhao, Weiwei; Li, Yanlong; Wang, Weiyun; Zhu, Xuan


    On the basis of the heavy metal (Cd, As, Pb, Zn, Cu, Cr, and Ni) control problem during the thermochemical recovery of phosphorus (P) from sewage sludge (SS), P-enriched sewage sludge ash (PSSA) was calcined at 1100°C. The effect of organic chlorinating agent (PVC) and inorganic chlorinating agent (MgCl2) on the fixed rate of P removal and the speciation transformation of heavy metal was studied. The removal of heavy metals Cd, Pb, As, Zn, and Cr exhibited an increasing tendency with the addition of chlorinating agent (PVC). However, an obvious peak under 100gCl/kg of PSSA appeared for Cu, owing to the presence of carbon and hydrogen in PVC. MgCl2 was found to be more effective than PVC in the removal of most heavy metals, such that up to 98.9% of Cu and 97.3% of Zn was effectively removed. Analyses of heavy metal forms showed that Pb and Zn occurred in the residue fraction after calcination. Meanwhile, the residue fraction of Cr, Ni, Cd, and Cu exhibited a decreasing tendency with the increase in the added chlorinating agent (MgCl2). Losses of P from PSSA were around 16.6% without the addition of chlorinating agent, which were greatly reduced to around 7.7% (PVC) and to only 1.7% (MgCl2). Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Heavy metals fluxes and speciation in the surface layer of urban soils in the province of Brescia (Italy) (United States)

    Peli, Marco; Raffelli, Giulia; Barontini, Stefano; Bostick, Benjamin C.; Donna, Filippo; Lucchini, Roberto G.; Ranzi, Roberto


    For the last forty years (1974-2015), a ferroalloy industry has been working in Bagnolo Mella, a municipality nearby the city of Brescia (Northern Italy), producing particulate emissions enriched in heavy metals: manganese (Mn) in particular, but also lead (Pb), iron (Fe), aluminum (Al) and arsenic (As). Although some of these metals are required trace elements for most living organisms and can be largely found in natural environments (e.g. Mn being the fifth most abundant metal in the Earth crust), they all lead to toxic effects when they contaminate work and life environments of the exposed population. Aiming at contributing to quantify the exposure of the population to environmental pollution near the factory, as well as the heavy metals possible tendency to migrate through the considered soil matrix, in this work we investigated metals speciation and fluxes within the Earth Critical Zone. The factory is located near residential areas in a plain characterised by little wind and shallow water table with a great number of water resurgences. Three test sites were identified among the pronest ones to particulate matter deposition, on the basis of data collected during a previous experimental field campaign and of the local wind rose. One more site was selected upwind to the factory as a reference site minimally prone to particulate matter deposition, on the basis of the previous investigations. Sites where lawns have been maintained at least for the last forty years where selected in order to avoid agriculture—induced effects on the metals movement. Total soil metal concentrations were measured by means of a portable X-Ray Fluorescence (XRF) device along the soil profiles, down to the depth of 40 cm from the soil surface. Four loose soil samples were collected at each site, at depths ranging from 5 to 30 cm, and they were later subjected to sequential extractions procedure and ICP—MS analyses, in order to investigate differences in heavy metals speciation along

  3. Speciation and risk of heavy metals in sediments and human health implications of heavy metals in edible nekton in Beibu Gulf, China: A case study of Qinzhou Bay. (United States)

    Gu, Yang-Guang; Lin, Qin; Yu, Zi-Ling; Wang, Xu-Nuo; Ke, Chang-Liang; Ning, Jia-Jia


    We investigated the total concentrations of heavy metals in surface sediments and nekton, along with sediment metal chemical partitioning in Qinzhou Bay of the Beibu Gulf. Cd was preferentially associated with the acid-soluble fraction and Pb mainly with the reducible fraction, whereas a major portion of Cr, Ni, Cu, and Zn was strongly associated with the residual fractions. A principal component analysis (PCA) in sediment metal speciation revealed three groupings (Cd; Pb; Cr, Ni, Cu, and Zn) that mainly resulted from different distributions of the metals in the various fractions. The Cr concentrations in nekton species were higher than maximum Cr concentrations permitted by the Chinese National Standard (GB 2762-2012). Taking as a whole, surface sediments of Qinzhou Bay had a 21% incidence calculation of adverse biological effects, based on the mean probable-effects-levels quotient. A human health risk assessment indicated no significant adverse health effects from consumption of nekton. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Biomonitoring and speciation of road dust for heavy metals using Calotropis procera and Delbergia sissoo

    Directory of Open Access Journals (Sweden)

    Santosh Kumar Prajapati


    Full Text Available The present study was conducted for identifying the important heavy metals present in the road dust and at the same time biomonitor them using Calotropis procera and Delbergia sissoo leaves. The study clearly indicated that both the plants can be used as biomonitor for As, Pb, Fe, V, Cd, Cr, Zn and Cu. The heavy metals were estimated using AAS-7000 (Shimadzu. Reason for selecting the plants were their abundance in the area and high air pollution indices. Presence of these heavy metals in the road dust can be attributed to the red soil and more importantly thermal power plants operating in the study area. Since plants are able to capture the road dust, they can also prevent the particulate pollution which is having adverse health impacts for humans.

  5. Heavy metal speciation, risk, and bioavailability in the sediments of rivers with different pollution sources and intensity. (United States)

    Tang, Wenzhong; Shan, Baoqing; Zhang, Hong; Zhu, Xiaolei; Li, Shanshan


    A comprehensive analysis of heavy metal speciation, risk, and bioavailability in the sediments of three rivers in northern China (Shaocun River (SR), Wangyang River (WR), and Xiao River (XR)) was conducted. The results showed that higher pollution input resulting from urbanization and industrialization caused higher heavy metal contents and bioavailable proportion in the studied sediments. Total contents of all studied metals (Cr, Cu, Ni, Pb, and Zn) in the sediments of SR, WR, and XR were 270.31, 902.62, and 2367.46 mg/kg, respectively. The average percentages of bioavailable fractions were 31.16, 61.73, and 81.69 %, respectively. Cr, Ni, and Pb were all mainly observed in the B4 (residual) fraction in the studied sediments, with an average percentage of 42.03, 48.19, and 55.08 %, respectively. Cu was mainly observed in the B2 (reducible) fraction (40.53 %). Zn was mainly observed in the B1 (exchangeable/acid soluble/carbonate) fraction (36.01 %), resulting in medium or high risk associated with Zn in the sediments of SR, WR, and XR. Sedimentary heavy metal risk and bioavailability associated with regional urbanization and industrialization should be taken into consideration with respect to the health of aquatic ecosystems.

  6. Leaching behavior of heavy metals and transformation of their speciation in polluted soil receiving simulated acid rain. (United States)

    Zheng, Shun-an; Zheng, Xiangqun; Chen, Chun


    Heavy metals that leach from contaminated soils under acid rain are of increasing concern. In this study, simulated acid rain (SAR) was pumped through columns of artificially contaminated purple soil. Column leaching tests and sequential extraction were conducted for the heavy metals Cu, Pb, Cd, and Zn to determine the extent of their leaching as well as to examine the transformation of their speciation in the artificially contaminated soil columns. Results showed that the maximum leachate concentrations of Cu, Pb, Cd, and Zn were less than those specified in the Chinese Quality Standards for Groundwater (Grade IV), thereby suggesting that the heavy metals that leached from the polluted purple soil receiving acid rain may not pose as risks to water quality. Most of the Pb and Cd leachate concentrations were below their detection limits. By contrast, higher Cu and Zn leachate concentrations were found because they were released by the soil in larger amounts as compared with those of Pb and Cd. The differences in the Cu and Zn leachate concentrations between the controls (SAR at pH 5.6) and the treatments (SAR at pH 3.0 and 4.5) were significant. Similar trends were observed in the total leached amounts of Cu and Zn. The proportions of Cu, Pb, Cd, and Zn in the EXC and OX fractions were generally increased after the leaching experiment at three pH levels, whereas those of the RES, OM, and CAR fractions were slightly decreased. Acid rain favors the leaching of heavy metals from the contaminated purple soil and makes the heavy metal fractions become more labile. Moreover, a pH decrease from 5.6 to 3.0 significantly enhanced such effects.

  7. [Study of the effect of earthworm Lumbricus terrestris on the speciation of heavy metals in soils]. (United States)

    El Gharmali, A; Rada, A; El Meray, M; Nejmeddine, A


    Evaluation of the effect of earthworm Lumbricus terrestris on the speciation of copper and cadmium was carried out on two types of soils with a high metallic contamination due to municipal wastes spreading. The concentrations of total dissolved metals were higher in the soil containing earthworms. This increase was larger for the soil submitted to disturbance by earthworms for a long time (3 months). The main chemical species in the lixiviates of all type of soils including controls, were labile forms of cadmium with 52 to 87% and stable forms of copper which represents 67 to 95% of total concentration of dissolved metal. In the solid phase, there was a slight transfer of cadmium and copper from the oxidizable fraction into the exchangeable and acid soluble fractions. This suggests that soil disturbance by earthworms increases the mobility of these metals particularly cadmium. On the contrary copper appears in lixiviates as non labile organic complexes. Analysis of the whole results showed differences between soils as regards the mobility of the metals studied, which reflected the role of the mains physico-chemical characteristics (pH, C.E.C. and total calcareous content).

  8. Chemical Speciation and Potential Mobility of Heavy Metals in the Soil of Former Tin Mining Catchment

    Directory of Open Access Journals (Sweden)

    M. A. Ashraf


    Full Text Available This study describes the chemical speciation of Pb, Zn, Cu, Cr, As, and Sn in soil of former tin mining catchment. Total five sites were selected for sampling and subsequent subsamples were collected from each site in order to create a composite sample for analysis. Samples were analysed by the sequential extraction procedure using optical emission spectrometry (ICP OES. Small amounts of Cu, Cr, and As retrieved from the exchangeable phase, the ready available for biogeochemical cycles in the ecosystem. Low quantities of Cu and As could be taken up by plants in these kind of acidic soils. Zn not detected in the bioavailable forms while Pb is only present in negligible amounts in very few samples. The absence of mobile forms of Pb eliminates the toxic risk both in the trophic chain and its migration downwards the soil profile. The results also indicate that most of the metals have high abundance in residual fraction indicating lithogenic origin and low bioavailability of the metals in the studied soil. The average potential mobility for the metals giving the following order: Sn > Cu > Zn > Pb > Cr > As.

  9. Speciation, sources, and risk assessment of heavy metals in suburban vegetable garden soil in Xianyang City, Northwest China (United States)

    Wang, Lijun; Tao, Wendong; Smardon, Richard C.; Xu, Xue; Lu, Xinwei


    Intensive anthropogenic activities can lead to soil heavy metal contamination resulting in potential risks to the environment and to human health. To reveal the concentrations, speciation, sources, pollution level, and ecological risk of heavy metals in vegetable garden soil, a total of 136 soil samples were collected from three vegetable production fields in the suburbs of Xianyang City, Northwest China. These samples were analyzed by inductively coupled plasma- atomic emission spectrometry and atomic fluorescence spectrometry. The results showed that the mean concentrations of Cd, Co, Cu, Mn, Pb, Zn, and Hg in vegetable garden soil were higher than the corresponding soil element background values of Shaanxi Province. The heavy metals studied in vegetable garden soil were primarily found in the residual fraction, averaging from 31.26% (Pb) to 90.23% (Cr). Considering the non-residual fractions, the mobility or potential risk was in the order of Pb (68.74%)>Co (60.54%)>Mn (59.28%) >Cd (53.54%) ≫Ni (23.36%) >Zn (22.73%)>Cu (14.93%)>V (11.81%)>Cr (9.78%). Cr, Mn, Ni, V, and As in the studied soil were related to soilforming parent materials, while Cu, Hg, Zn, Cd, Co, and Pb were associated with the application of plastic films, fertilizers, and pesticides, as well as traffic emissions and industrial fumes. Cr, Ni, V, and As presented low contamination levels, whereas Co, Cu, Mn, Pb, and Zn levels were moderate, and Cd and Hg were high. Ecological risk was low for Co, Cr, Cu, Mn, Pb, Zn, and As, with high risk observed for Cd and Hg. The overall pollution level and ecological risk of these heavy metals were high.

  10. Electrochemical metal speciation in colloidal dispersions

    NARCIS (Netherlands)

    Wonders, J.H.A.M.


    The term "heavy metals" is connected with toxicity. They form strong complexes with enzymes, other proteins and DNA in living organisms, which causes dysfunctioning and hence poisoning. In combination with the uptake mechanism of the organism, speciation of heavy metal determines the

  11. Heavy metals in sludge during anaerobic sanitary landfill: Speciation transformation and phytotoxicity. (United States)

    Yang, Kai; Zhu, Ying; Shan, Ranran; Shao, Yanqiu; Tian, Chao


    Sanitary landfill persists as a predominant sludge disposal method in particular in China. In this study, successive subsurface sludge samples (0.3 m deep) were collected from a bioreactor landfill unit where an anaerobic process took place during a 500 d period. The sludge samples were analyzed for total concentrations of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) and their species distributions, together with selected sludge chemical properties. In addition, the sludge samples were subjected to phytotoxicity testing. The results showed that the mobilities of Cd and Ni were decreased with landfill time, while the mobilities of Cr, Cu, Pb and Zn remained consistently low over the landfill period. The residual amounts of all these heavy metals were increased with landfill time, suggesting that the anaerobic sanitary landfill is an effective sludge stabilization method to reduce the ecological risk of these heavy metals. The increase in the sludge pH value with landfill time tended to promote the precipitation of heavy metals. Moreover, the sludge stabilization was found to be indicated by the formation of humic substance (HS) and volatilization of volatile matter (VM). The germination index (GI) values of barley (Hordeum vulgare L.) and Chinese cabbage (Brassica rapa chinensis) seeds grown in the 500 d anaerobically stabilized sludge were approximately 5.2- and 4.1-times higher than the values of those grown in the fresh sludge. The final sludge extract did not cause any significant inhibitory effect on the germination of the two types of seeds. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Total concentration and speciation of heavy metals in biosolids from urban origin; Concentracion total y especiacion de metales pesados en biosolidos de origen urbano origin

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Flores, Eduardo [Laboratorio de Ingenieria Ambiental, Instituto Tecnologico de Puebla, Puebla, Puebla (Mexico)]. E-mail:; Tornero Campante, Mario Alberto [Colegio de Postgraduados - Campus Puebla, San Pedro Cholula, Puebla (Mexico); Angeles Cruz, Yolanda [Laboratorio de Ingenieria Ambiental, Instituto Tecnologico de Puebla, Puebla, Puebla (Mexico); Bonilla y Fernandez, Noemi [Departamento de Agroecologia y Ambiente, Instituto de Ciencias - Benemerita Universidad Autonoma de Puebla, Puebla, Puebla (Mexico)


    The analysis of heavy metals is a very important task to asses the potential environmental and health risk associated with biosolids deposition in agricultural soil. However, it is widely accepted that determination of total concentration of heavy metals does not give an accurate estimation of the potential environmental impact. So, it is necessary to apply speciation studies to obtain suitable information about their bioavailability. This study was carried out on sewage sludge samples collected in a municipal waste-water treatment plant, located in Puebla City (Mexico). They are used for amendment agricultural soil. The speciation of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) was made using a sequential extraction procedure. The aim was to determine their concentration in bioavailability fractions. It was got the total concentration of heavy metals using acid digestion in a closed system and was determined with atomic absorption spectrometry. The total concentrations of heavy metals were lower than that established by Mexican legislation. The heavy metals are mainly associated with the mineral fraction and organic matter and consequently they show low bioavailability. [Spanish] El analisis de metales pesados es una actividad importante cuando se quiere valorar el potencial riesgo ambiental y de salud asociado con la utilizacion de biosolidos en suelos agricolas. Sin embargo, es ampliamente aceptado que la determinacion del contenido total no da una valoracion apropiada del impacto ambiental causado. Por lo tanto, es necesario realizar estudios de especiacion para obtener informacion mas detallada sobre su biodisponibilidad. Este estudio se llevo a cabo con muestras de lodos residuales producidos en una planta de tratamiento de aguas residuales ubicada en la ciudad de Puebla (Mexico). Estos biosolidos son utilizados para enmendar suelos agricolas. La especiacion de metales pesados (Cd, Cr, Cu, Ni, Pb y Zn) se realizo usando un procedimiento de extraccion secuencial

  13. Heavy metal pollution in vegetables grown in the vicinity of a multi-metal mining area in Gejiu, China: total concentrations, speciation analysis, and health risk. (United States)

    Li, Yanyan; Wang, Hongbin; Wang, Haijuan; Yin, Fei; Yang, Xiaoyan; Hu, Yongjun


    A field survey was conducted to investigate the present situation and health risk of arsenic (As), lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) in soils and vegetables in a multi-metal mining area, Gejiu, China. Furthermore, three vegetables (water spinach, potato, and summer squash) containing high metal concentrations were selected to further analyze metal speciation. The results showed that the average concentrations of five metals in soil exceeded the limiting values, and their bioavailable concentrations were significantly positively correlated to the total ones. Heavy metals in the edible parts of vegetables also exceeded the corresponding standards. The leaves of pakchoi, peppermint, and coriander had a strong metal-accumulative ability and they were not suitable for planting. Except the residue forms, the main forms of metals in the edible parts of three selected vegetables were ethanol-, NaCl-, and HAc-extractable fractions for As, Pb, and Cd, respectively; however, Cu was mainly presented as NaCl-extractable and Zn as HAc-extractable fractions. A high proportion of ethanol-extractable As showed that As bioactivity and toxic effects were the highest. Although the total and bioavailable Cd were high in soil, its speciation in vegetables was mainly presented as HAc-extractable fraction, which has a relatively low bioactivity. Lead and arsenic were imposing a serious threat on the local residents via vegetable consumption.

  14. Speciation of heavy metals in different grain sizes of Jiaozhou Bay sediments: Bioavailability, ecological risk assessment and source analysis on a centennial timescale. (United States)

    Kang, Xuming; Song, Jinming; Yuan, Huamao; Duan, Liqin; Li, Xuegang; Li, Ning; Liang, Xianmeng; Qu, Baoxiao


    Heavy metal contamination is an essential indicator of environmental health. In this work, one sediment core was used for the analysis of the speciation of heavy metals (Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb) in Jiaozhou Bay sediments with different grain sizes. The bioavailability, sources and ecological risk of heavy metals were also assessed on a centennial timescale. Heavy metals were enriched in grain sizes of Pb > Cd > Zn > Cu >Ni > Cr > As. Enrichment factors (EF) indicated that heavy metals in Jiaozhou Bay presented from no enrichment to minor enrichment. The potential ecological risk index (RI) indicated that Jiaozhou Bay had been suffering from a low ecological risk and presented an increasing trend since 1940s owing to the increase of anthropogenic activities. The source analysis indicated that natural sources were primary sources of heavy metals in Jiaozhou Bay and anthropogenic sources of heavy metals presented an increasing trend since 1940s. The principal component analysis (PCA) indicated that Cr, Mn, Ni, Cu and Pb were primarily derived from natural sources and that Zn and Cd were influenced by shipbuilding industry. Mn, Cu, Zn and Pb may originate from both natural and anthropogenic sources. As may be influenced by agricultural activities. Moreover, heavy metals in sediments of Jiaozhou Bay were clearly influenced by atmospheric deposition and river input. Copyright © 2017. Published by Elsevier Inc.

  15. Dispersion, Speciation, and Pollution Assessment of Heavy Metals Pb and Zn in Surface Sediment from Disturbed Ecosystem of Jeneberang Waters (United States)

    Najamuddin; Surahman


    Surface sediments were collected from seventeen stations in Jeneberang waters (riverine, estuarine, and marine). Lead (Pb) and zinc (Zn) concentrations were determined by atomic absorption spectrometry, and the speciation of metals was obtained by a sequential extraction procedure. Dispersion of Pb and Zn were found higher in the riverine and marine samples than the estuarine samples. Following speciation, the metals were found similar composition of fraction in the riverine and estuarine samples but any different in the marine samples. The results indicated that there is a change of dispersion pattern and speciation composition of metals due to the presence of the dam that lies at the boundary between the estuary and the river. The toxicity unit was indicated low toxicity level; pollution level was in weakly to moderately polluted while the aquatic environment risk attributed were no risky to light risk.

  16. Heavy metal

    African Journals Online (AJOL)

    niloticus after exposure to sublethal concentrations of heavy metals such as copper, lead and zinc for a 12-week period, using static renewable toxicity tests. The concentrations of the metals accumulated in the tissue of exposed fish were about 3-5 times higher than the concentrations detected in control fish.

  17. Transformation and speciation of typical heavy metals in soil aquifer treatment system during long time recharging with secondary effluent: Depth distribution and combination. (United States)

    Wei, Liangliang; Wang, Kun; Noguera, Daniel R; Jiang, Junqiu; Oyserman, Ben; Zhao, Ningbo; Zhao, Qingliang; Cui, Fuyi


    Soil aquifer treatment (SAT) systems rely on extensive physical and biogeochemical processes in the vadose zone and aquifer for water quality improvement. In this study, the distribution, quantitative changes, as well as the speciation characteristics of heavy metals in different depth of soils of a two-year operated lab-scale SAT was explored. A majority of the heavy metals in the recharged secondary effluent were efficiently trapped by the steady-state operated SAT (removal efficiency ranged from 74.7% to 98.2%). Thus, significant accumulations of 31.7% for Cd, 15.9% for Cu, 15.3% for Zn and 8.6% for Cr were observed for the top soil after 730 d operation, leading to the concentration (in μg g(-1)) of those four heavy metals of the packed soil increased from 0.51, 46.7, 61.0 and 35.7 to 0.66, 54.2, 70.4 and 38.8, respectively. By contrast, the accumulation of Mn and Pb were quite low. The residual species were the predominant fraction of the six heavy metals (ranged for 59.8-82.4%), followed by oxidisable species. Although the Zn, Cr, Cd, Cu and Mn were efficiently bounded onto the oxide components within the soil, the percentage of the labile metal fractions (water-, acid-exchangeable and reducible metal fractions) exhibited a slight increasing after 2 Y operation. Significantly heavy metals accumulation and slightly decreasing of the proportion of the stable fractions indicated a potentially higher environmental hazard for those six heavy metals after long-term SAT operation (especially for Cu, Zn and Cd). Finally, a linear relationship between the accumulation rate of metal species and the variation of soil organic carbon concentration and water extractable organic carbon was demonstrated. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Study of the heavy metals speciation in the atmospheric suspended particles in Sevilla (Spain); Estudio de la especiacion de metales pesados en la materia particulada atmosferica de la ciudad de Sevilla

    Energy Technology Data Exchange (ETDEWEB)

    Ternero Rodriguez, M.; Sequeiros Madueno, L.; Jimenez Sanchez, C.; Barragan de la Rosa, J.; Bello Lopez, M.; Fernandez Espinosa, A.J.; Perez Bernal, J.L. [Facultad de Quimica, Universidad de Sevilla (Spain)


    This work develops analytical methods for the heavy metals speciation in the atmospheric suspended particles. In base to these methods, we study the atmospheric contamination of the city of Seville, determining the metals Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb. We also study the effects of metallic species in the alteration processes on rocks material, in base to the SO{sub 2}/SO{sub 4}{sup {minus}{minus}}. The project develops in two years: in the first, we develop the methods of chemistry speciation based on the extraction with different reagents and the methods of physical speciation based on the particle size distribution with cascade impactors. Also, we develop the methodology for the environmental simulation of alteration processes, in base to the heterogeneous catalysis, by metallic ions, of the SO{sub 2} on the surface of the stone. In the second year we apply the methods of speciation to the study of the contamination by heavy metals in the city of Seville. This part divides in two phases: a first of the preliminary study in the city in order to identify the different polluting focuses, and a secondary of study of the contamination produced by punctual sources, in the more polluted points of the city. On the other hand, the study of the alteration processes of rock materials has centred on materials employees in monuments of the city and on application of the catalyzers found in the particulate matter of the true environment of the materials. (Author)

  19. Distribution, speciation, environmental risk, and source identification of heavy metals in surface sediments from the karst aquatic environment of the Lijiang River, Southwest China. (United States)

    Xu, Daoquan; Wang, Yinghui; Zhang, Ruijie; Guo, Jing; Zhang, Wei; Yu, Kefu


    The distribution and speciation of several heavy metals, i.e., As, Cd, Cr, Cu, Hg, Pb, and Zn, in surface sediments from the karst aquatic environment of the Lijiang River, Southwest China, were studied comparatively. The mean contents of Cd, Cu, Hg, Pb, and Zn were 1.72, 38.07, 0.18, 51.54, and 142.16 mg/kg, respectively, which were about 1.5-6 times higher than their corresponding regional sediment background values. Metal speciation obtained by the optimized BCR protocol highlighted the bioavailable threats of Cd, Cu, and Zn, which were highly associated with the exchangeable fraction (the labile phase). Hierarchical cluster analysis indicated that in sediments, As and Cr were mainly derived from natural and industrial sources, whereas fertilizer application might lead to the elevated level of Cd. Besides, Cu, Hg, Pb, and Zn were related to traffic activities. The effects-based sediment quality guidelines (SQGs) showed that Hg, Pb, and Zn could pose occasional adverse effects on sediment-dwelling organisms. However, based on the potential ecological risk assessment (PER) and risk assessment code (RAC), Cd was the most outstanding pollutant and posed the highest ecological hazard and bioavailable risk among the selected metals. Moreover, the metal partitioning between water and sediments was quantified through the calculation of the pseudo-partitioning coefficient (K P), and result implied that the sediments in this karst aquatic environment cannot be used as stable repositories for the metal pollutants.

  20. Heavy metal concentrations and speciation in riverine sediments and the risks posed in three urban belts in the Haihe Basin. (United States)

    Zhang, Chao; Shan, Baoqing; Tang, Wenzhong; Dong, Lixin; Zhang, Wenqiang; Pei, Yuansheng


    Heavy metal (Cr, Cu, Ni, Pb, and Zn) pollution and the risks posed by the heavy metals in riverine sediments in a mountainous urban-belt area (MB), a mountain-plain urban-belt area (MPB), and a plain urban-belt area (PB) in the Haihe Basin, China, were assessed. The enrichment factors indicated that the sediments were more polluted with Cu and Zn than with the other metals, especially in the MPB. The sediments in the MPB were strongly affected by Cu and Zn inputs from anthropogenic sources. The risk assessment codes and individual contamination factors showed that Zn was mobile and posed ecological risks, the exchangeable fractions being 21.1%, 21.2%, and 19.2% of the total Zn concentrations in the samples from the MB, MPB, and PB, respectively. Cr, Cu, and Zn in the sediments from the MPB were potentially highly bioavailable because the non-residual fractions were 56.2%, 54.9%, and 56.5%, respectively, of the total concentrations. The potential risks posed by the heavy metals (determined from the chemical fractions of the heavy metals) in the different areas generally decreased in the order MPB > MB > PB. Pictorial representation of cluster analysis results showed that urbanization development level could cause Cr and Zn pollution in the urban riverine sediments to become more severe. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Speciation and precipitation of heavy metals in high-metal and high-acid mine waters from the Iberian Pyrite Belt (Portugal). (United States)

    Durães, Nuno; Bobos, Iuliu; da Silva, Eduardo Ferreira


    Acid mine waters (AMW) collected during high- and low-flow water conditions from the Lousal, Aljustrel, and São Domingos mining areas (Iberian Pyrite Belt) were physicochemically analyzed. Speciation calculation using PHREEQC code confirms the predominance of Men+ and Me-SO4 species in AMW samples. Higher concentration of sulfate species (Me-SO4) than free ion species (Men+, i.e., Al, Fe, and Pb) were found, whereas opposite behavior is verified for Mg, Cu, and Zn. A high mobility of Zn than Cu and Pb was identified. The sulfate species distribution shows that Fe3+-SO42-, SO42-, HSO4-, Al-SO4, MgSO40, and CaSO40 are the dominant species, in agreement with the simple and mixed metal sulfates and oxy-hydroxysulphates precipitated from AMW. The saturation indices (SI) of melanterite and epsomite show a positive correlation with Cu and Zn concentrations in AMW, which are frequently retained in simple metal sulfates. Lead is well correlated with jarosite and alunite (at least in very acid conditions) than with simple metal sulfates. The Pb for K substitution in jarosite occurs as increasing Pb concentration in solution. Lead mobility is also controlled by anglesite precipitation (a fairly insoluble sulfate), where a positive correlation was ascertained when the SI approaches equilibrium. The zeta potential of AMW decreased as pH increased due to colloidal particles aggregation, where water species change from SO42- to OH- species during acid to alkaline conditions, respectively. The AMW samples were supersaturated in schwertmannite and goethite, confirmed by the Men+-SO4, Men+-Fe-O-OH, or Men+-S-O-Fe-O complexes identified by attenuated total reflectance infrared spectroscopy (ATR-IR). The ATR-IR spectrum of an AMW sample with pH 3.5 (sample L1) shows well-defined vibration plans attributed to SO4 tetrahedron bonded with Fe-(oxy)hydroxides and the Men+ sorbed by either SO4 or Fe-(oxy)hydroxides. For samples with lower pH values (pH ~ 2.5-samples SD1 and SD4), the

  2. The Speciation of heavy metals in marine sediments; La especiacion de los metales pesados en los sedimentos marinos

    Energy Technology Data Exchange (ETDEWEB)

    Arribas Rojo, P.; MaraNon Maison, E.; Garcia Mendez, R. [Departamento de Ingenieria Quimica, Tecnologia del Medio Ambiente, Universidad de Oviedo (Spain)


    The specification of metals is essential for establishing the toxicity hazard they represent. The area at the bottom of the water column, in this case sediments, is of particular interest. The different fractionation techniques applied, such as filtration, dialysis, ion exchange and photo oxidation, are described as well as aggressive techniques such as digestion and ultraviolet light. Several specification approaches combining these operations are presented together with acknowledgement of their authors. Separation is carried out according to size, charge, polarity and degree of oxidization or bonding force. Finally the factors affecting their bioavailability of trace metals are discussed. They can lead to bioaccumulation in organisms with consequent negative effects on the ecosystem. (Author) 63 refs.

  3. Effects of soil water content and organic matter addition on the speciation and bioavailability of heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Soriano, Maria C., E-mail: [Department of Soil Science, College of Agriculture and Life Sciences, North Carolina State University, Campus Box 7619, 101 Derieux Street, 2232 Williams Hall, Raleigh, NC 27695 (United States); Jimenez-Lopez, Jose C. [Department of Biological Sciences, College of Science, Purdue University, 201 S. University Street, West Lafayette, IN 47907 (United States)


    The mobility and bioavailability of cadmium, copper, lead and zinc were evaluated in three soils amended with different organic materials for two moisture regimes. Agricultural and reclamation activities impose fresh inputs of organic matter on soil while intensive irrigation and rainstorm increase soil waterlogging incidence. Moreover, scarcity of irrigation water has prompted the use of greywater, which contain variable concentrations of organic compounds such as anionic surfactants. Soils added with hay, maize straw or peat at 1% w/w were irrigated, at field capacity (FC) or saturated (S), with an aqueous solution of the anionic surfactant Aerosol 22 (A22), corresponding to an addition of 200 mg C/kg soil/day. Soil solution was extracted after one month and analysed for total soluble metals, dissolved soil organic matter and UV absorbance at 254 nm. Speciation analyses were performed with WHAM VI for Cd, Cu, Pb, and Zn. For selected scenarios, metal uptake by barley was determined. Metal mobility increased for all treatments and soils (Pb > Cu > Cd {>=} Zn) compared to control assays. The increase was significantly correlated (p < 0.05) with soil organic matter solubilisation for Cd (R = 0.68), Cu (R = 0.73) and Zn (R = 0.86). Otherwise, Pb release was related to aluminium solubilisation (R = 0.75), which suggests that Pb was originally co-precipitated with Al-DOC complexes in the solid phase. The effect of A22 in metal bioavailability, determined as free ion activities (FIA), was mainly controlled by soil moisture regime. For soil 3, metal bioavailability was up to 20 times lower for soil amended with hay, peat or maize compared to soil treated only with A22. When soil was treated with A22 at FC barley yield significantly decreased (p < 0.05) for the increase of Pb (R = 0.71) and Zn (R = 0.79) concentrations in shoot, while for saturated conditions such uptake was up to 3 times lower. Overall, metal bioavailability was controlled by solubilisation of soil

  4. In-situ electrochemical measurements of total concentration and speciation of heavy metals in acid mine drainage (AMD): assessment of the use of anodic stripping voltammetry. (United States)

    Jung, Hun-Bok; Yun, Seong-Taek; Kim, Soon-Oh; Jung, Myung Chae; So, Chil-Sup; Koh, Yong-Kwon


    We assessed the use of anodic stripping voltammetry (ASV) for in-situ determinations of both total concentration and speciation of dissolved heavy metals (Cd, Cu, Pb and Zn) in acid mine drainage (AMD). In the Kwangyang Au-Ag mine area of South Korea, different sites with varying water chemistry within an AMD were studied with a field portable anodic stripping voltammeter. Anodic stripping voltammetry after wet oxidation (acidification) was very sensitive enough to determine total concentration of dissolved Cd because Cd was dominantly present as 'labile' species, whilst the technique was not so effective for determining total Cu especially in the downstream sites from the retention pond, due to its complexation with organic matter. For dissolved Pb, the concentrations determined by ASV after wet oxidation generally agreed with those by ICP-AES. In the downstream samples (pH>5), however, ASV data after wet oxidation were lower than ICP-AES data because a significant fraction of dissolved Pb was present in those samples as 'inert' species associated with colloidal iron oxide particles. The determination of total dissolved Zn by ASV after wet oxidation appeared to be unsatisfactory for the samples with high Cu content, possibly due to the interference by the formation of Zn-Cu intermetallic compounds on the mercury coated electrode. In AMD samples with high dissolved iron, use of ultraviolet irradiation was not effective for determining total concentrations because humate destruction by UV irradiation possibly resulted in the removal of a part of dissolved heavy metals from waters through the precipitation of iron hydroxides.

  5. Biosolids and heavy metals in soils

    Directory of Open Access Journals (Sweden)

    Silveira Maria Lucia Azevedo


    Full Text Available The application of sewage sludge or biosolids on soils has been widespread in agricultural areas. However, depending on their characteristics, they may cause increase in heavy metal concentration of treated soils. In general, domestic biosolids have lower heavy metal contents than industrial ones. Origin and treatment method of biosolids may markedly influence their characteristics. The legislation that controls the levels of heavy metal contents in biosolids and the maximum concentrations in soils is still controversial. In the long-term, heavy metal behavior after the and of biosolid application is still unknown. In soils, heavy metals may be adsorbed via specific or non-specific adsorption reactions. Iron oxides and organic matter are the most important soil constituents retaining heavy metals. The pH, CEC and the presence of competing ions also affect heavy metal adsorption and speciation in soils. In solution, heavy metals can be present either as free-ions or complexed with organic and inorganic ligands. Generally, free-ions are more relevant in environmental pollution studies since they are readily bioavailable. Some computer models can estimate heavy metal activity in solution and their ionic speciation. Thermodynamic data (thermodynamic stability constant, total metal and ligand concentrations are used by the GEOCHEM-PC program. This program allows studying heavy metal behavior in solution and the effect of changes in the conditions, such as pH and ionic strength and the application of organic and inorganic ligands caused by soil fertilization.

  6. Study on the relationship between speciation of heavy metals and their ecotoxicity. I. Toxicity of Cu, Cd, Pb and Zn in seawater to three marine algae in the presence of different complexation agents (United States)

    Zhang, Manping; Wang, Juying; Bao, Junbo


    Heavy metal is a main pollutant in the marine ecosystem, so study on the effect of heavy metal on phytoplankton is important. Algae ( Chaetoceros sp., Dunaliella sp., Dicrateria zhanjiangenis Hu. var. sp.) were laboratory cultured to observe the effect of heavy metals on their growth. The effect of different metal ion concentration, the detoxication effect of complexation agents and the growth of algae in different media and different nutrition levels were studied to evaluate the effect of metal speciation. It is proved that trace amount of heavy metals can stimulate the growth of algae cells but that high concentration is lethal. The sequence of toxicity is Cd2+>Zn2+>Pb2+. In ordinary nutrition conditions, the detoxication sequence of complexation agents to Chaetoceros sp. is EDTA >sodium salicylate>sodium oxalate >sodium citrate>sulfanilic acid>O-phenanthroline. This is in good conformity with the stability constant sequence of these agents with copper and good evidence that toxicity of metal ion is related to its activity and not to its total concentration.

  7. Combined effects of antimony and sodium diethyldithiocarbamate on soil microbial activity and speciation change of heavy metals. Implications for contaminated lands hazardous material pollution in nonferrous metal mining areas. (United States)

    Zhu, Xiaozhe; Yao, Jun; Wang, Fei; Yuan, Zhimin; Liu, Jianli; Jordan, Gyozo; Knudsen, Tatjana Šolević; Avdalović, Jelena


    The combined effects of antimony (Sb) and sodium diethyldithiocarbamate (DDTC), a common organic flotation reagent, on soil microbial activity and speciation changes of heavy metals were investigated for the first time. The results showed that the exchangeable fraction of Sb was transformed to a stable residual fraction during the incubation period, and the addition of DDTC promoted the transformation compared with single Sb pollution, probably because DDTC can react with heavy metals to form a complex. In addition, the presence of DDTC and Sb inhibited the soil microbial activity to varying degrees. The growth rate constant k of different interaction systems was in the following order on the 28th day: control group ≥ single DDTC pollution > combined pollution > single Sb pollution. A correlation analysis showed that the concentration of exchangeable Sb was the primary factor that affected the toxic reaction under combined pollution conditions, and it significantly affected the characteristics of the soil microorganisms. All the observations provide useful information for a better understanding of the toxic effects and potential risks of combined Sb and DDTC pollution in antimony mining areas. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Characterization of changes in floc morphology, extracellular polymeric substances and heavy metals speciation of anaerobically digested biosolid under treatment with a novel chelated-Fe(2+) catalyzed Fenton process. (United States)

    He, Juanjuan; Yang, Peng; Zhang, Weijun; Cao, Bingdi; Xia, Hua; Luo, Xi; Wang, Dongsheng


    A novel chelated-Fe(2+) catalyzed Fenton process (CCFP) was developed to enhance dewatering performance of anaerobically digested biosolid, and changes in floc morphology, extracellular polymeric substances (EPS) and heavy metals speciation were also investigated. The results showed that addition of chelating agents caused EPS solubilization by binding multivalent cations. Like traditional Fenton, CCFP performed well in improving anaerobically digested sludge dewatering property. The highly active radicals (OH, O2(-)) produced in classical Fenton and CCFP were responsible for sludge flocs destruction and consequently degradation of biopolymers into small molecules. Furthermore, more plentiful pores and channels were presented in cake after Fenton treatment, which was conducive to water drainage under mechanical compression. Additionally, a portion of active heavy metals in the form of oxidizable and reducible states were dissolved under CCFP. Therefore, CCFP could greatly simplify the operating procedure of Fenton conditioning and improve its process adaptability for harmless treatment of biological sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. [Study on Speciation Analysis and Ecological Risk Assessment of Heavy Metals in Surface Sediments in Gansu, Ningxia and Inner Mongolia Sections of the Yellow River in Wet Season with HR-ICP-MS]. (United States)

    Ma, Xiao-ling; Liu, Jing-jun; Zuo, Hang; Huang, Fang; Liu, Ying


    In order to continuously study the contents, pollution condition and potential ecological risk of heavy metals in surface sediments in Gansu, Ningxia and Inner Mongolia sections of the Yellow River in wet seasons in different years, the speciation analysis of 9 kinds of heavy metals including Cd, Pb, Cr, Ni, Cu, V, Co, Zn and Mn, pollution condition and potential ecological risk of heavy metals in surface sediments from 10 sampling sites like Baotoufuqiao (S2), Shizuishantaolezhen (S6) and Wujinxia (S9) in Gansu, Ningxia and Inner Mongolia sections of the Yellow River in 2012 wet season were studied with BCR sequential extraction and high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS) based on our previous works. The results implied that the order of heavy metals average contents in the 10 sediment samples were the same: Mn>V> Zn>Cr>Cu>Ni>Pb>Co>Cd. In the sediments, heavy metals mainly existed in the form of residual fraction, which indicated that the bioavailability or environmental impact was low. Results of geo-accumulation indices (Igeo) showed that Igeo(CD), was the largest among the heavy metals with the strongest pollution, while IGEO(Mn)was the smallest. Enrichment factor (EF) indicated that only Cd and Cu were enriched at some sampling sites. In S5, because EFcd reached 4. 69, Cd was affected by human activities obviously and the result was consistent with I. Potential ecological risk index (RI) implied that the RI values in S1, S2 and S5 were between 150 and 300, which belonged to moderate polluting degree, while others were less than 150, belonging to light pollution degree. The results of this paper could not only provide reliable experimental data and theoretical basis for the relevant departments, but also supply the technical support for constructing mathematics model of sediments-pollutants transport, systematically researching the migration and transformation rule of persistent toxic substances and environmental assessment in

  10. Transport, fate and speciation of heavy metals (Pb, Zn, Cu, Cd) in mine drainage: geochemical modeling and anodic stripping voltammetric analysis. (United States)

    Yun, S T; Jung, H B; So, C S


    The maximum concentrations (ppb) of heavy metals in the mine drainage (pH: down to 3.3) of Chonam-ri creek in the abandoned Kwangyang gold-silver mine, South Korea, are 22600 Zn, 2810 Cu, 182 Cd, and 109 Pb. A small, limestone-infused retention pond, about 440 meters downstream from the waste dump, plays an important role in the removal of heavy metals: the factors of reduction for Zn, Cu, Cd, and Pb are 12, 24, 14, and 14, respectively. This is due to the pH increase (up to >5.4) accompanying adsorption onto and/or coprecipitation with Fe- and Al-hydroxides (goethite and gibbsite). From the waste dump to the pond, heavy metal concentrations also progressively decrease due to pH increase. Geochemical modeling (using the computer code WATEQ4F) predicts that free aqueous metal ions are dominant (mostly >70% for Cu and Zn, and >60% for Pb and Cd) in samples collected upstream from the pond, whereas complexing with sulfate, carbonate and hydroxyl ions becomes important in the samples collected downstream. The comparison between the concentrations of electrochemically labile species (determined by Anodic Stripping Voltammetry) and the result of computer modeling shows that Cd and Zn are present predominantly as labile inorganic species throughout the whole range of the creek. However, Cu and Pb in the samples collected downstream from the pond largely form electrochemically inert species (possibly, metal-organic complexes). The above results indicate that the retention pond is effective in reducing the toxicity of heavy metals, especially Cu and Pb.

  11. Heavy Metal Pollution of Vegetable Crops Irrigated with Wastewater ...

    African Journals Online (AJOL)


    exotic and traditional vegetables (samples = 240) irrigated with wastewater from some parts of Accra were studied. ... pesticides (McBride, 2003), as well as ...... Chemical speciation of heavy metals in sewage sludge and related matrices. In. Heavy Metals in Wastewater and Sludge. Treatment Process. (J. N. Lester, ed.), pp ...

  12. Atmospheric Heavy Metal Pollution

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 4. Atmospheric Heavy Metal Pollution - Development of Chronological Records and Geochemical Monitoring. Rohit Shrivastav. General Article Volume 6 Issue 4 April 2001 pp 62-68 ...

  13. Bioaccumulation of Heavy Metals

    African Journals Online (AJOL)


    acute toxicity and sublethal chronic action the devastating effects that the accumulation - ... surrounding waters. The results showed a programmes of heavy metals in aquatic strong and positive correlation (r = 0.97) ecosystems. between amounts of metals in the aquatic ...... Chemical composition of agricultural waste.

  14. Evaluation of copper speciation in model solutions of humic acid by mini-columns packed with Chelex-100 and new chelating agents: Application to speciation of selected heavy metals in environmental water samples

    Energy Technology Data Exchange (ETDEWEB)

    Kiptoo, Jackson K., E-mail: [Department of Chemistry, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi (Kenya); Ngila, J. Catherine [School of Chemistry, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Westville, Durban 4000 (South Africa); Silavwe, Ned D. [Department of Chemistry, University of Swaziland, P/Bag 4, Kwaluseni (Swaziland)


    A solid-phase extraction procedure using mini-columns packed with Chelex-100 and two new chelating agents based on poly(vinyl chloride) functionalized with 3-ferrocenyl-3-hydroxydithioacrylic acid and N,N'-[1,1'-dithiobis(ethylene)]-bis(salicylideneimine) (H{sub 2}sales) loaded on microcrystalline naphthalene, is reported. The columns were used to separate labile copper fractions in model solutions and in real samples with subsequent determination using electrothermal atomic absorption spectrometry (ETAAS). Various model solutions containing 20 {mu}g L{sup -1} of Cu{sup 2+} and 0.0, 0.2, 2.0 and 20.0 mg L{sup -1} of humic acid, respectively, and buffered to pH 6.0, 7.0 and 8.0 were considered. Results showed a decrease in labile copper fraction with increase in humic acid concentration. Application of the procedure to speciation of Cu, Ni, Zn and Pb in various environmental water samples yielded labile fractions in the range of 1.67-55.75% against a total dissolved fraction of 44.08-69.77%. Comparison of the three chelating agents showed that H{sub 2}sales had a weaker metal chelating strength than Chelex-100, but PVC-FSSH had comparable chelating strength to Chelex-100.

  15. Assessment of Heavy Metals Pollution in Dumpsites in Ilorin ...

    African Journals Online (AJOL)

    Speciation and distribution of heavy metals in soil controls the degree to which metals and their compounds are mobile, extractable, and plant available. Eight strategically located dumpsites in Ilorin metropolis (an averagely growing city and a state capital) were chosen for dumpsites-soil characteristics study. Both the ...

  16. Dynamic speciation analysis and bioavailability of metals in aquatic systems

    NARCIS (Netherlands)

    Leeuwen, van H.P.; Town, R.M.; Buffle, J.; Cleven, R.F.M.J.; Davison, W.; Puy, J.; Riemsdijk, van W.H.; Sigg, L.


    Dynamic metal speciation analysis in aquatic ecosystems is emerging as a powerful basis for development of predictions of bioavailability and reliable risk assessment strategies. A given speciation sensor is characterized by an effective time scale or kinetic window that defines the measurable metal


    African Journals Online (AJOL)


    2Department of Chemistry, Faculty of Physical Sciences, P.M.B. 1515, University of Ilorin,. Ilorin, Nigeria. (Received September 30, 2014; revised April 14, 2016) ... Moreover, the natural process, such as weathering of rocks and volcanic activities plays a noticeable role in enriching the water reservoirs with heavy metals [7, ...

  18. Distribution of Heavy Metal Pb


    Samawi, Muh. Farid; Tambaru, Rahmadi; Husain, Aida Ala; Burhanuddin, Andi Iqbal


    Distribution of Heavy Metal Pb in Benthic Organism and Sediment Bonebatang Island Waters Benthic organisms Bonebatang Island waters consist of branching hard corals, massive hard corals, soft corals, sponges, macroalgae, coralline algae, seagrass and mussels have the potential to accumulate heavy metals Pb from the water column. Results of studies have determined the rate of accumulation of heavy metals Pb some benthic organisms in the Bonebatang Island waters. Branching hard corals have a...

  19. Chemical Speciation of Some metal ions in Groundwaters of Yola ...

    African Journals Online (AJOL)

    Chemical speciation of some metal ions in groundwaters of Yola area using geochemical model were carried out to determine the water quality of the area using the PHREEQC speciation model. The study findings based on model calculations indicated that free Na+, Ca2+, Mg2+ and K+ ions are present and the ...

  20. Speciation in Metal Toxicity and Metal-Based Therapeutics

    Directory of Open Access Journals (Sweden)

    Douglas M. Templeton


    Full Text Available Metallic elements, ions and compounds produce varying degrees of toxicity in organisms with which they come into contact. Metal speciation is critical to understanding these adverse effects; the adjectives “heavy” and “toxic” are not helpful in describing the biological properties of individual elements, but detailed chemical structures are. As a broad generalization, the metallic form of an element is inert, and the ionic salts are the species that show more significant bioavailability. Yet the salts and other chelates of a metal ion can give rise to quite different toxicities, as exemplified by a range of carcinogenic potential for various nickel species. Another important distinction comes when a metallic element is organified, increasing its lipophilicity and hence its ability to penetrate the blood brain barrier, as is seen, for example, with organic mercury and tin species. Some metallic elements, such as gold and platinum, are themselves useful therapeutic agents in some forms, while other species of the same element can be toxic, thus focusing attention on species interconversions in evaluating metal-based drugs. The therapeutic use of metal-chelating agents introduces new species of the target metal in vivo, and this can affect not only its desired detoxification, but also introduce a potential for further mechanisms of toxicity. Examples of therapeutic iron chelator species are discussed in this context, as well as the more recent aspects of development of chelation therapy for uranium exposure.

  1. Contamination of soils by heavy metals. New Speciation from the kinetic aspect; La contaminacion de los suelos por metales pesados. Una nueva aproximacion a la especiacion desde el punto de vista cenitico

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Morales, J. L.; Sales, D. [Universidad de Cadiz (Spain); Bermond, A. [Institut National Agronomique. Paris (France)


    Nowadays the public opinion is very sensitive with the problem associated to the heavy metals soil contamination. Environmental catastrophes like the events happened in Aznalcollar and its future effects have shown the serious problem associated to this form of contamination. The study of the different existent species of the metals, as well as its possible biodisponibility, is a section that the diverse authors in a very different way have approached. Often, when they are carried out chemical methods of especiacion, one does not keep in mind the dependence with the time that you/they have the extraction phenomenon. However, this parameter is probably strongly linked with the mobility or biodisponibility of the metals appearance in the soil. The present work applies the kinetic especiacion to the heavy metals present in a cultivation soil in which the agronomic sludge application of a wastewater treatment plant has been made. The results of the copper content of these soils in comparison with a reference parcel are presented. (Author) 20 refs.

  2. Trace metal characterization and speciation in geothermal effluent by multiple scanning anodic stripping voltammetry and atomic absorption analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, B.R.


    Recent studies have shown geothermal power plants to have a significant environmental impact on the ground water of the area. The heavy metals arsenic and mercury are special problems, as both are concentrated by flora and fauna exposed to the effluent waters. Because the toxicity of these and other metallic pollutants present in geothermal effluent depends on the chemical form, or speciation, of the particular metal, any serious study of the environmental impact of a geothermal development should include studies of trace metal speciation, in addition to trace metal concentration. This proposal details a method for determining metal speciation in dilute waters. The method is based on ion-exchange and backed by atomic absorption spectrometry and multiple scanning anodic stripping voltammetry. Special laboratory studies will be performed on mercury, arsenic and selenium speciation in synthetic geothermal water. The method will be applied to three known geothermal areas in Washington and Oregon, with emphasis on the speciation of mercury, arsenic and selenium in these waters. The computer controlled electrochemical instrumentation was built and tested. Using this instrumentation, a new experimental procedure was developed to determine the chemical form (speciation) of metal ions in very dilute solutions (ng/ml). This method was tested on model systems including Pb, Cd, and As with C1/sup -/, CO/sub 3//sup 2 -/ and glycine ligands. Finally, the speciation of lead in a geothermal water was examined and the PbC1/sup +/ complex was observed and quantified.


    African Journals Online (AJOL)

    Adeyinka Odunsi

    The mean metal content of cassava leaf indicated that all the metals were higher in the leaf at high ... components of petroleum hydrocarbons ..... Atmos. Environ. 40: 5929-5941. Onder, S., Dursun, S., Gezgin, S. and. Demirbas, A. (2007). Determination. Accumulation of heavy metal pollutants on soil microbial population.

  4. Heavy Metal Stars (United States)


    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

  5. Speciation and determination of priority metals in sediments of Oyun ...

    African Journals Online (AJOL)

    This work was carried out to determine the concentrations, bioavailability and mobility of priority metals in sediments of Oyun River, Sango, Ilorin, Nigeria. The river sediments were sampled at six selected locations and the samples were analyzed for some certain priority metals to determine the concentration, speciation and ...

  6. Heavy Metals in Marine Pollution Perspective-A Mini Review (United States)

    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

  7. Metallic speciation in environmental samples. La especiacion metalica en muestras medioambientales

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Uria, J.E.


    A review about chemical speciation in environmental samples was developed. Starting from definition of speciation, characteristic techniques and squemes for speciation more adequate for the characterization of the several organic/inorganic metal-species was considered. Finally, the possible future tendences of speciation techniques was also considered. (Author) 27 refs.

  8. Electrochemical metal speciation in natural and model polyelectrolyte systems

    NARCIS (Netherlands)

    Hoop, van den M.A.G.T.


    The purpose of the research described in this thesis was to examine the applicability of electro-analytical techniques in obtaining information on the speciation of metals, i.e. their distribution over different physico-chemical forms, in aquatic systems containing charged macromolecules.

  9. Heavy metals in Mindhola river estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Rokade, M.A; Mandalia, A

    The heavy metal concentrations are studied along the Mindhola river estuary. Surface and bottom water samples were collected using Niskin Sampler. The sediment samples were collected using a Van Veen grab. The heavy metal concentration is estimated...

  10. Metal transformation as a strategy for bacterial detoxification of heavy metals. (United States)

    Essa, Ashraf M M; Al Abboud, Mohamed A; Khatib, Sayeed I


    Microorganisms can modify the chemical and physical characters of metals leading to an alteration in their speciation, mobility, and toxicity. Aqueous heavy metals solutions (Hg, Cd, Pb, Ag, Cu, and Zn) were treated with the volatile metabolic products (VMPs) of Escherichia coli Z3 for 24 h using aerobic bioreactor. The effect of the metals treated with VMPs in comparison to the untreated metals on the growth of E. coli S1 and Staphylococcus aureus S2 (local isolates) was examined. Moreover, the toxic properties of the treated and untreated metals were monitored using minimum inhibitory concentration assay. A marked reduction of the treated metals toxicity was recorded in comparison to the untreated metals. Scanning electron microscopy and energy dispersive X-ray analysis revealed the formation of metal particles in the treated metal solutions. In addition to heavy metals at variable ratios, these particles consisted of carbon, oxygen, sulfur, nitrogen elements. The inhibition of metal toxicity was attributed to the existence of ammonia, hydrogen sulfide, and carbon dioxide in the VMPs of E. coli Z3 culture that might responsible for the transformation of soluble metal ions into metal complexes. This study clarified the capability of E. coli Z3 for indirect detoxification of heavy metals via the immobilization of metal ions into biologically unavailable species. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Heavy metals in sea turtles

    Energy Technology Data Exchange (ETDEWEB)

    Witkowski, S.A. (Millersville State College, PA); Frazier, J.G.


    Bone and barnacle samples from sea turtles (Hepidochelys olivacea) in Ecuador were analyzed for manganese, iron, copper, zinc and lead. Analysis was performed by flame atomic absorption spectroscopy. Results show that zinc and iron levels in bone and barnacles were greater than copper, manganese and lead levels. The significance of the findings is difficult to interpret because so little is known about baseline levels and physiological effects of heavy metals in the animals. (JMT)

  12. Heavy metals precipitation in sewage sludge

    NARCIS (Netherlands)

    Marchioretto, M.M.; Rulkens, W.H.; Bruning, H.


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

  13. Coordination chemistry of two heavy metals: I, Ligand preferences in lead(II) complexation, toward the development of therapeutic agents for lead poisoning: II, Plutonium solubility and speciation relevant to the environment

    Energy Technology Data Exchange (ETDEWEB)

    Neu, Mary Patricia [Univ. of California, Berkeley, CA (United States)


    The coordination chemistry and solution behavior of the toxic ions lead(II) and plutonium(IV, V, VI) have been investigated. The ligand pKas and ligand-lead(II) stability constants of one hydroxamic acid and four thiohydroaxamic acids were determined. Solution thermodynamic results indicate that thiohydroxamic acids are more acidic and slightly better lead chelators than hydroxamates, e.g., N-methylthioaceto-hydroxamic acid, pKa = 5.94, logβ120 = 10.92; acetohydroxamic acid, pKa = 9.34, logβ120 = 9.52. The syntheses of lead complexes of two bulky hydroxamate ligands are presented. The X-ray crystal structures show the lead hydroxamates are di-bridged dimers with irregular five-coordinate geometry about the metal atom and a stereochemically active lone pair of electrons. Molecular orbital calculations of a lead hydroxamate and a highly symmetric pseudo octahedral lead complex were performed. The thermodynamic stability of plutonium(IV) complexes of the siderophore, desferrioxamine B (DFO), and two octadentate derivatives of DFO were investigated using competition spectrophotometric titrations. The stability constant measured for the plutonium(IV) complex of DFO-methylterephthalamide is logβ120 = 41.7. The solubility limited speciation of 242Pu as a function of time in near neutral carbonate solution was measured. Individual solutions of plutonium in a single oxidation state were added to individual solutions at pH = 6.0, T = 30.0, 1.93 mM dissolved carbonate, and sampled over intervals up to 150 days. Plutonium solubility was measured, and speciation was investigated using laser photoacoustic spectroscopy and chemical methods.

  14. Relationship between metal speciation in soil solution and metal adsorption at the root surface of ryegrass

    NARCIS (Netherlands)

    Kalis, E.J.J.; Temminghoff, E.J.M.; Town, R.M.; Unsworth, E.R.; Riemsdijk, van W.H.


    Received for publication October 12, 2007. The total metal content of the soil or total metal concentration in the soil solution is not always a good indicator for metal availability to plants. Therefore, several speciation techniques have been developed that measure a defined fraction of the total

  15. The Heavy Metal Subculture and Suicide. (United States)

    Stack, Steven; And Others


    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.…

  16. Industrial hygiene of selected heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Woodring, J.L.


    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.

  17. Poisoning of domestic animals with heavy metals

    Directory of Open Access Journals (Sweden)

    Velev Romel


    Full Text Available The term heavy metal refers to a metal that has a relatively high density and is toxic for animal and human organism at low concentrations. Heavy metals are natural components of the Earth's crust. They cannot be degraded or destroyed. To a small extent they enter animal organism via food, drinking water and air. Some heavy metals (e.g cooper, iron, chromium, zinc are essential in very low concentrations for the survival of all forms of life. These are described as essential trace elements. However, when they are present in greater quantities, like the heavy metals lead, cadmium and mercury which are already toxic in very low concentrations, they can cause metabolic anomalies or poisoning. Heavy metal poisoning of domestic animals could result, for instance, from drinking-water contamination, high ambient air concentrations near emission sources, or intake via the food chain. Heavy metals are dangerous because they tend to bioaccumulate in a biological organism over time. Manifestation of toxicity of individual heavy metals varies considerably, depending on dose and time of exposure, species, gender and environmental and nutritional factors. Large differences exist between the effects of a single exposure to a high concentration, and chronic exposures to lower doses. The aim of this work is to present the source of poisoning and toxicity of some heavy metals (lead, mercury, cadmium, thallium, arsenic, as well as new data about effects of those heavy metals on the health of domestic animals. .

  18. Heavy Metal - Exploring a magnetised metallic asteroid (United States)

    Wahlund, Jan-Erik; Andrews, David; Futaana, Yoshifumi; Masters, Adam; Thomas, Nicolas; De Sanctis, Maria Cristina; Herique, Alain; Retherford, Kurt; Tortora, Paolo; Trigo-Rodriguez, Joseph; Ivchenko, Nickolay; Simon, Sven


    We propose a spacecraft mission (Heavy Metal) to orbit and explore (16) Psyche - the largest M-class metallic asteroid in the main belt. Recent estimates of the shape, 279×232×189 km and mass, 2.7×10(19) kg make it one of the largest and densest of asteroids, and together with the high surface radar reflectivity and the spectral data measured from Earth it is consistent with a bulk composition rich in iron-nickel. The M5 mission Heavy Metal will investigate if (16) Psyche is the exposed metallic core of a planetesimal, formed early enough to melt and differentiate. High-resolution mapping of the surface in optical, IR, UV and radar wavebands, along with the determination of the shape and gravity field will be used to address the formation and subsequent evolution of (16) Psyche, determining the origin of metallic asteroids. It is conceivable that a cataclysmic collision with a second body led to the ejection of all or part of the differentiated core of the parent body. Measurements at (16) Psyche therefore provide a possibility to directly examine an iron-rich planetary core, similar to that expected at the center of all the major planets including Earth. A short-lived dynamo producing a magnetic field early in the life of (16) Psyche could have led to a remnant field (of tens of micro Tesla) being preserved in the body today. (16) Psyche is embedded in the variable flow of the solar wind. Whereas planetary magnetospheres and induced magnetospheres are the result of intense dynamo fields and dense conductive ionospheres presenting obstacles to the solar wind, (16) Psyche may show an entirely new 'class' of interaction as a consequence of its lack of a significant atmosphere, the extremely high bulk electrical conductivity of the asteroid, and the possible presence of intense magnetic fields retained in iron-rich material. The small characteristic scale of (16) Psyche ( 200 km) firmly places any solar wind interaction in the "sub-MHD" scale, in which kinetic

  19. Heavy metals in Antarctic organisms

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  20. Especiação de metais-traço em sedimentos de florestas de manguezais com Avicennia e Rhizophora Metal speciation under Rhizophora and Avicennia mangles

    Directory of Open Access Journals (Sweden)

    Regina Célia Bastos de Andrade


    Full Text Available Speciation studies of Fe, Cr, Co, Ni and Cu on reactive fraction (adsorved on oxides, hydroxides, carbonates and clay minerals and pyrite were performed in Avicennia schaueriana and Rhizophora mangle sediments from Amapá shoreline-Brazil. The soil under Avicennia showed a higher heavy metal concentration in reactive fraction than under Rhizophora. The soil under Rhizophora showed low heavy metal bioavailability, having an increasing association with pyrite across sediment section.

  1. Divergent biology of facultative heavy metal plants. (United States)

    Bothe, Hermann; Słomka, Aneta


    Among heavy metal plants (the metallophytes), facultative species can live both in soils contaminated by an excess of heavy metals and in non-affected sites. In contrast, obligate metallophytes are restricted to polluted areas. Metallophytes offer a fascinating biology, due to the fact that species have developed different strategies to cope with the adverse conditions of heavy metal soils. The literature distinguishes between hyperaccumulating, accumulating, tolerant and excluding metallophytes, but the borderline between these categories is blurred. Due to the fact that heavy metal soils are dry, nutrient limited and are not uniform but have a patchy distribution in many instances, drought-tolerant or low nutrient demanding species are often regarded as metallophytes in the literature. In only a few cases, the concentrations of heavy metals in soils are so toxic that only a few specifically adapted plants, the genuine metallophytes, can cope with these adverse soil conditions. Current molecular biological studies focus on the genetically amenable and hyperaccumulating Arabidopsis halleri and Noccaea (Thlaspi) caerulescens of the Brassicaceae. Armeria maritima ssp. halleri utilizes glands for the excretion of heavy metals and is, therefore, a heavy metal excluder. The two endemic zinc violets of Western Europe, Viola lutea ssp. calaminaria of the Aachen-Liège area and Viola lutea ssp. westfalica of the Pb-Cu-ditch of Blankenrode, Eastern Westphalia, as well as Viola tricolor ecotypes of Eastern Europe, keep their cells free of excess heavy metals by arbuscular mycorrhizal fungi which bind heavy metals. The Caryophyllaceae, Silene vulgaris f. humilis and Minuartia verna, apparently discard leaves when overloaded with heavy metals. All Central European metallophytes have close relatives that grow in areas outside of heavy metal soils, mainly in the Alps, and have, therefore, been considered as relicts of the glacial epoch in the past. However, the current

  2. Heavy metals in the volcanic environment and thyroid cancer. (United States)

    Vigneri, R; Malandrino, P; Gianì, F; Russo, M; Vigneri, P


    been rarely measured in the thyroid. Heavy metal accumulation and metabolism in the thyroid or the carcinogenic activity of different doses and different speciation of metals has not been investigated. These studies are now warranted to better understand thyroid biology and heavy metal role in human thyroid carcinogenesis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Hazards of heavy metal contamination. (United States)

    Järup, Lars


    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


    Directory of Open Access Journals (Sweden)

    Justyna Koc-Jurczyk


    Full Text Available Industrialization and urbanization result in increase of heavy metals released into the environment (soil, lakes, rivers, seas, oceans, groundwater. Studies on biosorption of heavy metals are aimed to specify types of microorganisms which could efficiently bind metals. This approach has a very important significance for both slowing down metals exploitation by recovery, and also reduction of environmental pollution by decrease of their excessive concentration. Recent studies have reported about the capabilities of fungi, algae, yeasts, bacteria, waste and agricultural residues or materials containing chitosan derived from crustacean shells as a biosorbents. Biohydrometallurgy could be considered as a new “green” technology of heavy metals removal from wastewater.

  5. Heavy metal uptake of Geosiphon pyriforme (United States)

    Scheloske, Stefan; Maetz, Mischa; Schüßler, Arthur


    Geosiphon pyriforme represents the only known endosymbiosis between a fungus, belonging to the arbuscular mycorrhizal (AM) fungi, and cyanobacteria (blue-green algae). Therefore we use Geosiphon as a model system for the widespread AM symbiosis and try to answer some basic questions regarding heavy metal uptake or resistance of AM fungi. We present quantitative micro-PIXE measurements of a set of heavy metals (Cu, Cd, Tl, Pb) taken up by Geosiphon-cells. The uptake is studied as a function of the metal concentration in the nutrient solution and of the time Geosiphon spent in the heavy metal enriched medium. The measured heavy metal concentrations range from several ppm to some hundred ppm. Also the influence of the heavy metal uptake on the nutrition transfer of other elements will be discussed.

  6. Biosorption of Heavy Metals by Biomass


    AKÇİN, Göksel


    Wetland plants are successfully used in the biosorption of heavy metals in natural and constructed wetlands. In this study, the removal of heavy metals by water hyacinth [ Eichhornia crassipes (Mart.)Solms)] were investigated. The plants were grown under control in the Turkish climate. The biosorption was dependent on factors such as metal concentration, constant temperature, pH and relative moisture. The plants were exposed to different metal concentrations of Chromium(III), Chromi...

  7. Heavy Metal Music and Adolescent Suicidal Risk. (United States)

    Lacourse, Eric; Claes, Michel; Villeneuve, Martine


    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…

  8. Heavy Metal Levels, Physicochemical Properties and Microbial ...

    African Journals Online (AJOL)


    Heavy Metal Levels, Physicochemical Properties and Microbial Diversity of Soil Matrix from University Solid Waste ... characteristics of soil samples from five different waste collection sites within the University of Benin, Benin City and evaluated using ...... phytoremediation of heavy metals contaminated soils: A review.

  9. Nickel speciation in cement-stabilized/solidified metal treatment filtercakes

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Amitava, E-mail: [J. Bennett Johnston, Sr., Center for Advanced Microstructures and Devices, Louisiana State University, Baton Rouge, LA 70806, USA (United States); Stegemann, Julia A., E-mail: [Centre for Resource Efficiency & the Environment, Department of Civil, Environmental & Geomatic Engineering, University College London, Chadwick Building, Gower Street, London WC1E 6BT, UK (United Kingdom)


    Highlights: • XAS shows the same Ni speciation in untreated and stabilized/solidified filtercake. • Ni solubility is the same for untreated and stabilized/solidified filtercake. • Leaching is controlled by pH and physical encapsulation for all binders. - Abstract: Cement-based stabilization/solidification (S/S) is used to decrease environmental leaching of contaminants from industrial wastes. In this study, two industrial metal treatment filtercakes were characterized by X-ray diffractometry (XRD), thermogravimetric and differential thermogravimetric analysis (TG/DTG) and Fourier transform infrared (FTIR); speciation of nickel was examined by X-ray absorption (XAS) spectroscopy. Although the degree of carbonation and crystallinity of the two untreated filtercakes differed, α-nickel hydroxide was identified as the primary nickel-containing phase by XRD and nickel K edge XAS. XAS showed that the speciation of nickel in the filtercake was unaltered by treatment with any of five different S/S binder systems. Nickel leaching from the untreated filtercakes and all their stabilized/solidified products, as a function of pH in the acid neutralization capacity test, was essentially complete below pH ∼5, but was 3–4 orders of magnitude lower at pH 8–12. S/S does not respeciate nickel from metal treatment filtercakes and any reduction of nickel leaching by S/S is attributable to pH control and physical mechanisms only. pH-dependent leaching of Cr, Cu and Ni is similar for the wastes and s/s products, except that availability of Cr, Cu and Zn at decreased pH is reduced in matrices containing ground granulated blast furnace slag.

  10. Monitoring metal speciation in the rivers meuse and rhine using DGT

    NARCIS (Netherlands)

    Cleven, Rob; Nur, Yusuf; Krystek, Petra; Van Den Berg, Gerard

    Although a number of metal speciation methods are nowadays available, most water quality regulations are based on total metal concentrations. One of the main reasons for the ignorance of speciation is the lack of methods with potentiality for monitoring. Conditions that have to be met by such

  11. Biomolecules for Removal of Heavy Metal. (United States)

    Singh, Namita Ashish


    Patents reveal that heavy metals are natural constituents of the earth's crust, but some heavy metals like cadmium, lead, mercury, arsenic etc. are injurious to living organisms at higher concentration. Nowadays, anthropogenic activities have altered geochemical cycles and biochemical balance of heavy metals. Biomolecules are used nowadays for removal of heavy metals compared to other synthetic biosorbents due to their environmental friendly nature and cost effectiveness. The goal of this work is to identify the role of biomolecules like polysaccharides, polypeptides, natural compounds containing aromatic acid etc. for heavy metal removal by bio sorption. It has been observed that efficiency of biomolecules can be increased by functionalization e.g. cellulose functionalization with EDTA, chitosan with sulphur groups, alginate with carboxyl/ hydroxyl group etc. It was found that the porous structure of aerogel beads improves both sorption and kinetic properties of the material. Out of polypeptides metallothionein has been widely used for removal of heavy metal up to 88% from seawater after a single centrifugation. These cost effective functionalized biomolecules are significantly used for remediation of heavy metals by immobilizing these biomolecules onto materials. Copyright© Bentham Science Publishers; For any queries, please email at

  12. Heavy metals in municipal solid waste deposits

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, P.


    Extensive use of heavy metals in modern society influences routes followed by fluxes on the surface of the Earth. The changed flow paths may be harmful for the balance of biological systems at different levels, micro-organisms, human beings and whole ecosystems, since the toxicity of heavy metals is determined by their concentrations and chemical forms. Despite the low mobility of heavy metals (Zn, Cu, Pb, Cr, Ni and Cd) in municipal landfills, it was found that extensive transformations of the binding forms of heavy metal take place within the waste mass during the degradation of the waste. These changes appear to be closely related to the development of early diagenetic solid phases, i.e. new secondary solid phases formed in the waste. The heavy metals often constitute a minor part of these phases and the bindings include several forms such as adsorption, complexation, coprecipitation, precipitation, etc. It was also found that the associations between heavy metals and solid phases are dominated by several binding forms to one specific substrate rather than bindings to various solid phases. The mobility of iron and manganese seems to increase during the processes involved in waste degradation due to the solution of oxide/hydroxide phases, while the heavy metals appear to become less mobile due to their binding to organic compounds and sulphides. However, one exception in this case may be nickel. Another aspect of the transformation of heavy metals is the accumulation of pools of heavy metals which can become susceptible to environmental changes, such as oxidation or acidification. However, the risk of increased mobilization caused by lower pH values seem to be limited since municipal solid waste has a large buffer capacity. 66 refs, 9 figs, 3 tabs 66 refs, 9 figs, 3 tabs

  13. TiO2nanoparticles in sediments: Effect on the bioavailability of heavy metals in the freshwater bivalve Corbicula fluminea. (United States)

    Fan, Xiulei; Wang, Chao; Wang, Peifang; Hu, Bin; Wang, Xun


    Most studies investigating the influence of TiO 2 NPs on heavy metal bioavailability have focused on the aqueous phase; however, few have examined the sediments containing more nanoparticles. Here, we investigated the effects of TiO 2 NPs on heavy metal bioavailability in C. fluminea in sediments. The interactions between the TiO 2 NPs and metals in sediments, the influence of TiO 2 NPs on metals levels in aqueous phase and geochemical speciation were also explored. The results indicated the large adsorption capacity of TiO 2 NPs and the strong adsorption affinity to metals caused the metals adsorbed on nanoparticles, which decreased the metals concentrations in water phase. Changes in metal speciation caused by metals in EXC, CAR, and IMO partly transported from sediments to TiO 2 NPs during the aging of sediments. Heavy metals contents in C. fluminea tissues were in the order of gill>visceral mass>mantle>foot and increased with the increasing TiO 2 NPs contents in sediments. TiO 2 NPs enhanced the bioavailability of metals in the speciation of EXC, CAR, and IMO in sediments by the Trojan horse effects. The results can facilitate a more realistic evaluation of the environmental risks of TiO 2 NPs to benthic organisms in heavy metal-contaminated sediments. Copyright © 2017. Published by Elsevier B.V.


    Directory of Open Access Journals (Sweden)


    Full Text Available ABSTRACT The application of foliar fungicides in vineyards and orchards can increase soil concentration of heavy metals such as copper (Cu and zinc (Zn, up to the toxicity threshold for fruit trees and cover crops. However, some agronomic practices, such as liming, addition of organic fertilizers, cultivation of soil cover crops and inoculation of young plants with arbuscular mycorrhizal fungi can decrease the availability and the potential of heavy metal toxicity to fruit trees. This review aims to compile and present information about the effects of increasing concentrations of heavy metals, especially Cu and Zn, on soils cultivated with fruit trees and provides some agronomic practices of remediation. Information about the sources of heavy metals found in soils cultivated with fruit trees are presented; mechanisms of absorption, transport, accumulation and potential toxicity to plants are described.


    African Journals Online (AJOL)

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    The dietary supplements of macronutrients and trace heavy metals from herbs and ... sustain temperature up to 230 oC and pressure up to 625 psi. .... manufacture of energy maintenance of health of reproductive system, immune system and.


    African Journals Online (AJOL)


    Key words: Water, contamination degree, geochemical factors, public health, heavy metal. INTRODUCTION. Earth is unique among other planets in the solar system since it has an environment where it has been able to thrive. Pure water rarely occurs in nature due to the capacity to dissolve numerous substances of heavy.

  17. Heavy metal removal and recovery using microorganisms

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  18. Thin mercury film electrodes in dynamic speciation studies of metals = (United States)

    Rocha, Luciana Sarabando da

    In the present work the performance and applicability of the thin mercury film electrode (TMFE) in the dynamic speciation of trace metals was investigated. Two different electroanalytical stripping techniques were used: the classical anodic stripping voltammetry (ASV) and a recent developed technique, scanning stripping chronopotentiometry (SSCP). The ion-exchange and the mass transport features of novel mixed coatings of two sulfonated cation-exchange polymers with dissimilar characteristics, Nafion (NA) and poly(sodium 4-styrenesulfonate) (PSS) were evaluated, prior to its application in the field of trace metal analysis. Suitable NA-PSS polymer coatings could be used in the modification of TMFE, presenting a high sensitivity, reproducibility, mechanical stability and adequate antifouling properties in the ASV determination of trace metal cations in complex media. Also the features of the PSS polyelectrolyte layers for ion-exchange voltammetry (IEV) were evaluated. The goal was to search for the best conditions to obtain stable PSS coated electrodes, which could present high negative charge densities in order to enhance the electrostatic accumulation of cations within the film, thus enlarging the ASV signal. The applicability and performance of the TMFE in the trace metal speciation studies, by SSCP, were for the first time exploited. The optimized TMFE presented a high sensitivity and resolution, being an excellent complement to the conventional mercury electrodes and could be use for 1-day term with no significant variation in the SCP analytical signal and no apparent degradation. The calculated SSCP curves were in excellent agreement with experimental data at the TMFE and the stability constant (K), calculated from the shift in the SSCP half-wave potential, of two labile metal-complex systems were in good agreement with the ones obtained using the conventional Hanging mercury drop electrode (HMDE) and those predicted by theory. Additionally, the experimental

  19. Heavy metals in equine biological components

    Directory of Open Access Journals (Sweden)

    Maria Verônica de Souza


    Full Text Available The objective of this research was to determine the concentration of heavy metals in the blood (Pb, Ni and Cd, serum (Cu and Zn and hair (Pb, Ni, Cd, Cu and Zn of horses raised in non-industrial and industrial areas (with steel mill, and to verify the possibility to use these data as indicators of environmental pollution. The samples were collected during summer and winter, aiming to verify animal contamination related to environment and season of the year. Copper and Zn contents determined in the serum and Cd and Ni contents obtained in the blood indicated no contamination effects of industries. For some animals, contents of Pb in the blood were higher than those considered acceptable for the species, but without relationship with industrialization and without clinical signs of Pb intoxication. The heavy metals evaluated on the hair of horses in this study were not increased with the presence of industries, but Cu and Cd contents were influenced by the season. The contents of some heavy metals in biological components analyzed were influenced by season sampling; however, serum, blood and hair may not be suitable to indicate differences in environmental contamination between the two contrasting areas. Most part of the heavy metal contents was lower or close to the reference values for horses. Serum, blood and hair components from horses may not be effective as indicators of environmental pollution with heavy metals. Industrialization and seasons have no effects on most part of heavy metals contents from those components.

  20. Studies on the occurrence and distribution of heavy metals in ...

    African Journals Online (AJOL)


    induced pollution and high levels of heavy metals can often be attributed to anthropogenic influences, rather ... of heavy metal ions on bacteria and determined the heavy metals by bioassay. Collins and Stotzky (1992) ... the microbe, which alter the net charge of the cell. Once heavy metals are discharged into estuarine and ...

  1. Heavy metals contamination of Chrysichthys nigrodigitatus and ...

    African Journals Online (AJOL)



    Sep 27, 2010 ... and the lowest concentration was in the muscle. These findings agree with the result of Manahan (1992) that lower concentrations of heavy metals occurred in gills and bones than in the intestines and muscles. The metal, iron was found to have the highest concen- tration in the tissues of C. nigrodigitatus, ...

  2. Removal of heavy metals from biowaste : modelling of heavy metal behaviour and development of removal technologies

    NARCIS (Netherlands)

    Veeken, A.H.M.


    In the Netherlands, recycling of solid organic waste streams as compost only becomes possible if the compost complies with the heavy metals standards of the BOOM decree. This dissertation focuses on the removal of heavy metals from biowaste, i.e. the source separated organic fraction of

  3. Speciation of Metals and Assessment of Contamination in Surface Sediments from Daya Bay, South China Sea

    Directory of Open Access Journals (Sweden)

    Jie Yang


    Full Text Available The contents, speciation, source factors and potential ecological risks of the selected metals (Cr, Ni, Cu, Pb, Zn, Cd and As were analyzed in surface sediments from Daya Bay (DYB. The results show that, with the exception of Pb, metal concentrations have decreased at all sites over the past decade. The distribution features of these concentrations represent a ring shape that descends from shore to bay by varying degrees. Speciation analysis showed that Cr, Ni, Cu, Zn and As exist mainly in the residual fraction and, thus, are of low bioavailability, while Cd and Pb were found to be abundant in the non-residual fraction and, thus, have high potential mobility. The ratio of heavy metals in non-residual form in descending order is Pb (78.83%, Cd (78.65%, Cu (48.54%, Zn (48.10%, Ni (38.31%, Cr (28.43% and As (27.76%. The ratio of Pb content is the highest, meaning the highest mobility of Pb. The metals’ potential ecological risks to the environment were also assessed using the methods of the mean effect range-median quotient and the criteria of risk assessment code. The results showed that Cd presents the highest risk, and Pb and Cu are generally considered to be medium risks in the sub-basins of Daya Bay. The principal component analysis (PCA revealed that natural coastal weathering and erosion of rock caused the highest input, followed by mariculture and industrial wastewater and, finally, domestic sewage discharge.

  4. Heavy Metal Poisoning and Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Eman M. Alissa


    Full Text Available 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.

  5. Recovering heavy rare earth metals from magnet scrap (United States)

    Ott, Ryan T.; McCallum, Ralph W.; Jones, Lawrence L.


    A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

  6. Chelant extraction of heavy metals from contaminated soils. (United States)

    Peters, R W


    The current state of the art regarding the use of chelating agents to extract heavy metal contaminants has been addressed. Results are presented for treatability studies conducted as worst-case and representative soils from Aberdeen Proving Ground's J-Field for extraction of copper (Cu), lead (Pb), and zinc (Zn). The particle size distribution characteristics of the soils determined from hydrometer tests are approximately 60% sand, 30% silt, and 10% clay. Sequential extractions were performed on the 'as-received' soils (worst case and representative) to determine the speciation of the metal forms. The technique speciates the heavy metal distribution into an easily extractable (exchangeable) form, carbonates, reducible oxides, organically-bound, and residual forms. The results indicated that most of the metals are in forms that are amenable to soil washing (i.e. exchangeable+carbonate+reducible oxides). The metals Cu, Pb, Zn, and Cr have greater than 70% of their distribution in forms amenable to soil washing techniques, while Cd, Mn, and Fe are somewhat less amenable to soil washing using chelant extraction. However, the concentrations of Cd and Mn are low in the contaminated soil. From the batch chelant extraction studies, ethylenediaminetetraacetic acid (EDTA), citric acid, and nitrilotriacetic acid (NTA) were all effective in removing copper, lead, and zinc from the J-Field soils. Due to NTA being a Class II carcinogen, it is not recommended for use in remediating contaminated soils. EDTA and citric acid appear to offer the greatest potential as chelating agents to use in soil washing the Aberdeen Proving Ground soils. The other chelating agents studied (gluconate, oxalate, Citranox, ammonium acetate, and phosphoric acid, along with pH-adjusted water) were generally ineffective in mobilizing the heavy metals from the soils. The chelant solution removes the heavy metals (Cd, Cu, Pb, Zn, Fe, Cr, As, and Hg) simultaneously. Using a multiple-stage batch extraction

  7. Heavy metal hazards of Nigerian herbal remedies

    Energy Technology Data Exchange (ETDEWEB)

    Obi, E. [Toxicology Unit, Department of Pharmacology, College of Health Sciences, Nnamdi Azikiwe University, Nnewi (Nigeria); Akunyili, Dora N. [National Agency of Food and Drug Administration and Control (NAFDAC), Lagos (Nigeria); Ekpo, B. [Department of Biochemistry, College of Medical Sciences, Abia State University, Uturu (Nigeria); Orisakwe, Orish E. [Toxicology Unit, Department of Pharmacology, College of Health Sciences, Nnamdi Azikiwe University, Nnewi (Nigeria)]. E-mail:


    The uses of herbal products are not regulated in Nigeria and in many low-income countries and are freely available to everyone. The safety of these herbal medicines is poorly understood. This study characterizes the content of cadmium, copper, iron, nickel, selenium, zinc, lead and mercury in a random sample of Nigerian traditional products. Ready-to-use herbal products were purchased from the open market and digested using HNO{sub 3}.The heavy metal content of the digested filtrate was determined by atomic absorption spectrometry Uni-cam Model 929. The result showed that 100% of the samples contained elevated amounts of heavy metals. These data alert us to the possibility of heavy metal toxicity from herbal products in Nigeria. The public health hazards from ingestion of herbal medicines should be identified and disclosed by in-depth risk assessment studies.

  8. Heavy Metal Pollution Around International Hatay Airport

    Directory of Open Access Journals (Sweden)

    Abdullah Özkan


    Full Text Available In this study, it was aimed to determine the heavy metal pollution in the agricultural lands around Hatay airport and travel possible alteration in the amount of heavy metal on the land in accordance with the distance to the airport. For this purpose, the airport was chosen as the center and 27 soil samples were obtained around the airport at 2 km intervals in depth ranging from 0 to 30 cm. Lead (Pb, cadmium (Cd, nickel (Ni, chrome (Cr, cobalt (Co, aluminium (Al, iron (Fe, copper (Cu, manganese (Mn and zinc (Zn elements in soil samples were analysed using MP-AES instrument by DTPA method. (3 repetition for each sample. As a result of the analysis, heavy metal concentrations were found as Pb 0-1.45 mg/kg, Cd 0-0.220 mg/kg, Ni 0-3.95 mg/kg, Cr 0-0.780 mg/kg, Co 0-0.270 mg/kg, Al 0-0.700 mg/kg, Fe 1.47- 16.2 mg/kg, Cu 0.400-5.35 mg/kg, Mn 0-19 mg/kg and Zn 0.050-3.14 mg/kg. When comparing the obtained data through this study with allowable concentrations of heavy metals in soil of Environment and Forest Directorates Guidance, it was determined that the heavy metal concentration of the soil does not pose any problems in terms of heavy metal pollution. Besides, iron concentration was decreased when the distance to the airport is increased.

  9. A study of chemical speciation of metals in aquatic bottom sediment ...

    African Journals Online (AJOL)

    The species and total mean metal concentrations of some potentially environmental toxic metals (manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and lead (Pb)) in ... The speciation result revealed that high levels of these metals studied (Mn, Fe, Cu, Zn, and Pb) were associated with exchangeable and carbonate bound ...

  10. Transfer of heavy metals through terrestrial food webs: a review. (United States)

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


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

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

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, J.G.


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

  12. Metal speciation in soil and health risk due to vegetables consumption in Bangladesh. (United States)

    Islam, Md Saiful; Ahmed, Md Kawser; Habibullah-Al-Mamun, Md


    This study was conducted to investigate the contamination level of heavy metals in soil and vegetables, chemical speciation, and their transfer to the edible part of vegetables. Metals were analyzed using inductively coupled plasma mass spectrometer (ICP-MS). The ranges of Cr, Ni, Cu, As, Cd, and Pb in agricultural soils were 3.7-41, 3.9-36, 3.7-46, 2.3-26, 0.6-13, and 4.5-32 mg/kg, respectively. The metals were predominantly associated with the residual fractions of 39, 41, 40, 40, 34, and 41 % for Cr, Ni, Cu, As, Cd, and Pb, respectively. Considering the metal transfer from soil to the edible part of vegetables, the mean transfer factors (TFs) were in the descending order of Cu > Ni > Cr > Pb > As > Cd. In the edible tissues of vegetables, the concentrations of As, Cd, and Pb in most vegetable samples exceeded the maximum permissible levels, indicating not safe for human consumption. Total target hazard quotient (THQ) of the studied metals (except Cr) from all vegetables were higher than 1, indicated that if people consume these types of vegetables in their diet, they might pose risk to these metals. Total values of carcinogenic risk (CR) were 3.2 for As and 0.15 for Pb which were higher than the US Environmental Protection Agency (USEPA) threshold level (0.000001), indicating that the inhabitants consuming these vegetables are exposed to As and Pb with a lifetime cancer risk.

  13. Esterase resistant to inactivation by heavy metals

    KAUST Repository

    El, Dorry Hamza


    EstATII is an esterase that a halotolerant, thermophilic and resistant to a spectrum of heavy metals including toxic concentration of metals. It was isolated from the lowest convective layer of the Atlantis II Red Sea brine pool. The Atlantis II brine pool is an extreme environment that possesses multiple harsh conditions such as; high temperature, salinity, pH and high concentration of metals, including toxic heavy metals. A fosmid metagenomic library using DNA isolated from the lowest convective layer this pool was used to identify EstATII. Polynucleotides encoding EstATII and similar esterases are disclosed and can be used to make EstATII. EstATII or compositions or apparatuses that contain it may be used in various processes employing lipases/esterases especially when these processes are performed under harsh conditions that inactivate other kinds of lipases or esterases.

  14. Heavy metal mining using microbes. (United States)

    Rawlings, Douglas E


    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.

  15. Pyrolized biochar for heavy metal adsorption (United States)

    Removal of copper and lead metal ions from water using pyrolized plant materials. Method can be used to develop a low cost point-of-use device for cleaning contaminated water. This dataset is associated with the following publication:DeMessie, B., E. Sahle-Demessie , and G. Sorial. Cleaning Water Contaminated With Heavy Metal Ions Using Pyrolyzed Banana Peel Adsorbents. Separation Science and Technology. Marcel Dekker Incorporated, New York, NY, USA, 50(16): 2448-2457, (2015).

  16. Heavy metal detoxification in eukaryotic microalgae. (United States)

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


    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.

  17. Microwave enhanced stabilization of heavy metal sludge. (United States)

    Hsieh, Ching-Hong; Lo, Shang-Lien; Chiueh, Pei-Te; Kuan, Wen-Hui; Chen, Ching-Lung


    A microwave process can be utilized to stabilize the copper ions in heavy metal sludge. The effects of microwave processing on stabilization of heavy metal sludge were studied as a function of additive, power, process time, reaction atmosphere, cooling gas, organic substance, and temperature. Copper leach resistance increased with addition of aluminum metal powder, with increased microwave power, increased processing time, and using a gaseous environment of nitrogen for processing and air for cooling [N2/air]. The organic in the sludge affected stabilization, whether or not the organic smoldered. During heating in conventional ovens, exothermic oxidation of the organic resulted in sludge temperatures of about 500 degrees C for oven control temperatures of 200-500 degrees C. After microwave heating dried the sludge, the sludge temperature rose to 500 degrees C. The reaction between copper ions and metal aluminum in the dried sludge should be regarded as a solid phase reaction. Adding aluminum metal powder and reaction temperature were the key parameters in stabilizing copper in the heavy metal sludge, whether heated by microwave radiation or conventional oven. The mass balance indicates insignificant volatization of the copper during heating.

  18. Electrokinetic removal of heavy metals from soil

    Directory of Open Access Journals (Sweden)

    Puvvadi Venkata Sivapullaiah


    Full Text Available Removal of heavy metal ions from soils by electrokinetic treatment has several advantages. The extent of removal, however, is both soil specific and ion specific. The conditions to be maintained have to be established based on laboratory studies. With a view to maximize the removal of metal ions the trends of removal of heavy metal ions such as iron, nickel and cadmium form a natural Indian kaolinitic red earth during different conditions maintained in the electrokinetic extraction process are studied. A laboratory electrokinetic extraction apparatus was assembled for this purpose. Attempts are also made to elucidate the mechanism of removal of the metal ions from soil. The composition of the flushing fluid, voltage and duration of extraction are varied. While dilute acetic acid has been used to neutralize the alkalinity that develops at the cathode, EDTA solution has been used to desorb heavy metals from clay surface. Generally the extent of removal was proportional to the osmotic flow. Nickel and Cadmium are more effectively removed than iron. The percentage removal of Ni is generally proportional to the osmotic flow but shows sensitivity to the pH of the system. There is an optimum voltage for removal of metal ions from soil. The removal of iron was negligible under different conditions studied.

  19. Hydroponics reducing effluent's heavy metals discharge. (United States)

    Rababah, Abdellah; Al-Shuha, Ahmad


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

  20. Heavy Metal Pollution Assessment by Partial Geochemical ...

    African Journals Online (AJOL)

    Mn and Fe oxides are powerful absorbents of heavy metal cations in soils and stream sediments therefore considered in this environmental geochemical investigation. Steam sediment samples were collected from Au-Ag and Pb-Zn-Cu mineralized areas of the Rodalquilar old gold mine, located in the southeastern part of ...

  1. Heavy metals phytoremediation using Typha domingensis ...

    African Journals Online (AJOL)

    Phytoremediation as a tool employs aquatic macrophytes as a principal and inexpensive strategy for controlling environmental pollution. It is achieved through various mechanisms such as phytoextraction, phytostabilization, and phytovolatilization. In this study, heavy metal content of a contaminated drainage that empties ...

  2. Heavy Metals and Related Trace Elements. (United States)

    Leland, Harry V.; And Others


    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)

  3. Assessment of physicochemical qualities, heavy metal ...

    African Journals Online (AJOL)



    Aug 23, 2012 ... Key words: Aquatic biota, contamination, pollution, public health, microbial indicators, toxic effects. INTRODUCTION. Water is ... commonly occur in water and wastewater can be divided into four separate groups. ... heavy/toxic metal contamination of the Shanomi creek of the Warri river, hence the need for ...

  4. Electrodialytic decontamination of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik K.; Karlsmose, Bodil


    Electrodialytic remediation of heavy metal polluted soil is a newly developed method, which combines the electrokinetic mevement of ions in soil with the principle of electrodialytis. The method has been proven to work in laboratory scale and at present two types of pilot plant tests are made....

  5. Evaluation of Physicochemical Properties and Heavy Metals ...

    African Journals Online (AJOL)

    Physicochemical properties of municipal dumpsite compost in Kano metropolis and concentration of heavy metals were investigated. Analysis was carried out by atomic absorption spectrometry (Buck Scientific VPG 210). The results shows that the compost pH (6.63-8.19), electric conductivity of compost (638-933μs/cm), ...

  6. 202 197 Heavy Metals and Microbial Contamin

    African Journals Online (AJOL)


    Dec 2, 2008 ... ABSTRACT: The heavy metal and microbial contaminants levels were evaluated in a commercial polyherbal .... (Cowan and Steel) was carried out to identify ... Statistical Analysis. Analysis of data obtained from this study was done using Excel Microsoft software. Analysis of Variance (ANOVA) was used for.


    African Journals Online (AJOL)


    ABSTRACT. Phytoremediation as a tool employs aquatic macrophytes as a principal and inexpensive strategy for controlling environmental pollution. It is achieved through various mechanisms such as phytoextraction, phytostabilization, and phytovolatilization. In this study, heavy metal content of a contaminated drainage ...


    African Journals Online (AJOL)

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    ABSTRACT. The macronutrients and heavy metals content of different parts of a locally found herb named ... inductively coupled plasma optical emission spectrometry (ICP-OES) and atomic absorption spectrophotometry. (AAS). .... involved in the formation of vitamin B12 or cobalamin and as such essential for erythrocyte.

  9. Environmental remediation from heavy metal pollution using ...

    African Journals Online (AJOL)

    Graft copolymers of polyacrlamide-grafted gum arabic were synthesized, blended with Moringa oleifera and characterized by IR spectroscopy. The potentials of the products to remove heavy metals from aqueous solutions were studied at room temperature (30oC) and this was experimented on iron (III) ions (Fe3+).


    African Journals Online (AJOL)


    MOLLUSCS AND CRUSTACEANS FROM TWO SELECTED CITIES IN. NIGERIA. Ogundiran ... are good sources of animal protein if they are found in contamination free environment. Key words: Heavy metals, ..... commonly used traditional preservation methods include sun-drying and hot-smoking. [28]. The sun-drying ...

  11. Comparative anatomy, nutraceutical potentials and heavy metal ...

    African Journals Online (AJOL)

    This study investigated the anatomical features, nutraceutical potentials and heavy metal compositions in two varieties of Lasianthera africana (P. Beauv) which is a member of the family Icacinaceae predominantly found mostly in southern Nigeria. The anatomical studies were carried out with free hand sectioning using a ...

  12. Heavy metal sequestration by humic substances during phyto-treatment of sewage sludges

    Energy Technology Data Exchange (ETDEWEB)

    Peruzzi, E.; Doni, S.; Macci, C.; Ceccanti, B.; Masciandaro, G.


    The presence of heavy metals in sludges stabilized in a reed bed system, may affect their use for agricultural purposes; however, the environmental impact of sludges depends on the availability and phyto toxicity of their heavy metal. The aim of this paper was to determine the effectiveness of a reed bed (Phragmites Australia) sludge treatment system in two urban wastewater treatment plants in Italy after two-year period of operation: by estimating the process of sludge stabilization, following conventional and non conventional parameters related with the evolution of organic matter quality (Water soluble Carbon, Dehydrogenase activity, Fulvic Acids, Humic Acids, Pyrolytic indices or organic matter Mineralization and Humification); by following the heavy metal speciation bioavailability in sludges. (Author)

  13. Comprehensive risk assessment of heavy metals in lake sediment from public parks in Shanghai. (United States)

    Yang, Jing; Chen, Ling; Liu, Li-Zao; Shi, Wei-Ling; Meng, Xiang-Zhou


    Rapid urbanization has caused potential pollution of heavy metal in Shanghai. A comprehensive pollution study of heavy metals (Cd, Cu, Pb, and Zn) in 35 lake surface sediments from city parks in the four different urbanized areas of Shanghai was conducted. Intensive human activities caused moderate enrichment of the four metals in highly urbanized areas, especially Cd with the significant enrichment in the central urban core area. However, the levels of the four metals in all the sediments were lower than the corresponding consensus-based Probable Effect Concentration, indicating adverse effects not to occur frequently. The integrated pollution assessments of multiple heavy metals also suggested low ecological risk and 15-29 percent probability of toxicity in most of sediments. The metal speciation analysis showed that Cd, Cu, Pb, and Zn were dominated by the non-residual fractions and thus they have high mobility and bioavailability, indicating significant anthropogenic sources. According to the Risk Assessment Code, Cd had the highest bioavailable fraction and represented high or very high risk, followed by Zn with medium or high risks in most of samples, while no or low risk was found for Cu and Pb at most sites because they were dominated by reducible and residual fractions. Correlation analysis showed that chemical fractions of heavy metals were prone to transform among each other if environmental conditions changed. Therefore, in view of anthropogenic inputs and speciation distribution, heavy metals with very high bioavailability at very low total levels and those with low bioavailability at very high total levels should not be ignored. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Metabolic Demands of Heavy Metal Drumming

    Directory of Open Access Journals (Sweden)

    Bryan Romero


    Full Text Available Background: The drum set involves dynamic movement of all four limbs. Motor control studies have been done on drum set playing, yet not much is known about the physiological responses to this activity. Even less is known about heavy metal drumming. Aims: The purpose of this study was to determine metabolic responses and demands of heavy metal drumming. Methods: Five semi-professional male drummers (mean ± SD age = 27.4 ± 2.6 y, height = 177.2 ± 3.8 cm, body mass = 85.1 ± 17.8 kg performed four prescribed and four self-selected heavy metal songs. Oxygen consumption (VO2, minute ventilation (VE and respiratory exchange ratio (RER were measured using a metabolic cart.  Heart rate (HR was measured using a heart rate monitor. VO2max was determined using a graded cycle ergometer test. Results: The results indicated a metabolic cost of 6.3 ± 1.4 METs and heart rate of 145.1 ± 15.7 beats·min-1 (75.4 ± 8.3% of age-predicted HRmax. VO2 peak values reached approximately 90% of the drummer’s VO2max when performing at the fastest speeds. According to these results, heavy metal drumming may be considered vigorous intensity activity (≥ 6.0 METs. The relative VO2max of 40.2 ± 9.5 mL·kg·min-1 leads to an aerobic fitness classification of “average” for adult males. Conclusions: The metabolic demands required during heavy metal drumming meet the American College of Sports Medicine guidelines for the development of health related fitness.  Keywords: Drum set, Exercise physiology, VO2, Music

  15. Heavy Metal Uptake by Novel Miscanthus Seed-Based Hybrids Cultivated in Heavy Metal Contaminated Soil (United States)

    Krzyżak, Jacek; Pogrzeba, Marta; Rusinowski, Szymon; Clifton-Brown, John; McCalmont, Jon Paul; Kiesel, Andreas; Mangold, Anja; Mos, Michal


    When heavy metal contaminated soils are excluded from food production, biomass crops offer an alternative commercial opportunity. Perennial crops have potential for phytoremediation. Whilst the conditions at heavy metal contaminated sites are challenging, successful phytoremediation would bring significant economic and social benefits. Seed-based Miscanthus hybrids were tested alongside the commercial clone Miscanthus × giganteus on arable land, contaminated with Pb, Cd and Zn near Katowice. Before the randomized experimental plots were established (25m2 plots with plant density 2/m2) `time-zero' soil samples were taken to determine initial levels of total (aqua regia) and bioavailable (CaCl2 extraction) concentration of Pb, Cd and Zn. After the growing season plant material was sampled during autumn (October, green harvest) and winter (March, brown harvest) to determine differences in heavy metal uptake. Results after the first growing season are presented, including the plot establishment success, biomass yield and heavy metal uptake.

  16. Microfocus study of metal distribution and speciation in tissue extracted from revised metal on metal hip implants

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Alister J [Department of Orthopaedic Surgery, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Rd, London W6 8RF (United Kingdom); Sandison, Ann [Department of Histopathology, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Rd, London W6 8RF (United Kingdom); Quinn, Paul; Mosselmans, J Frederick W [Science Division, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxon, OX11 0DE (United Kingdom); Sampson, Barry [Department of Clinical Biochemistry, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Rd, London W6 8RF (United Kingdom); Atkinson, Kirk D [8 Nuclear Department Defence Academy College of Management and Technology HMS Sultan Military Road Gosport PO12 3BY (United Kingdom); Skinner, John A [Department of Orthopaedics, Royal National Orthopaedic Hospital, HA7 4LP (United Kingdom); Goode, Angela [Dept of Materials, Imperial College London, SW7 2AZ (United Kingdom); Powell, Jonathan J, E-mail: [Medical Research Council Human Nutrition Research Centre, Cambridge CB1 9NL (United Kingdom)


    Unexplained tissue inflammation in metal-on-metal hip replacements is suspected to be caused by implant-derived nanoparticles. The aim of this study was to investigate the nature of the metal particles in tissue surrounding metal-on-metal (MOM) hips that has been extracted during revision. Mapping of tissue surrounding the failed MOM hips was performed using microfocus X-ray Fluorescence (XRF). This revealed mainly Cr which was localized to the cellular regions. There was co-localisation of Co, were present, to areas of high Cr abundance. XANES of the tissue and appropriate standards revealed that the most common species were Cr(III) and Co(II). EXAFS analysis of the tissue and various metal standards revealed that the most abundant implant-related species was Cr(III) phosphate. Different tissue preparation methods, including frozen sectioning, were examined but were found not to affect the distribution or speciation of the metals in the tissue.

  17. Effect of operating conditions on speciation and bioavailability of trace metals in submerged anaerobic membrane bioreactors. (United States)

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


    This study investigated the effect of changes in pH (7, 6.5 and 6), hydraulic retention time (HRT) (6h, 4h, and 2h), solids retention time (SRT) (100d and 25d) on the speciation of trace metals (TMs) in submerged anaerobic membrane bioreactors (SAMBRs). The results showed that the metal retention capacity of SAMBRs reduced when the pH, HRT and SRT were reduced i.e. up to 21.9%, 39.1%, and 17.1%, respectively, but it was also found that the speciation of these TMs generally shifted towards highly bioavailable fractions i.e. Soluble and Exchangeable. The degree of shifting in speciation depended on the affinity of the TMs for anaerobic sludge and their sensitivity to the changes. TMs with the most and the least significant changes in speciation were Fe and Mn, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Heavy Metal Induced Antibiotic Resistance in Bacterium LSJC7

    National Research Council Canada - National Science Library

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


    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...

  19. Speciation of trace metals in the Baltic Sea with focus on the Euphotic zone


    Gelting, Johan


    Physicochemical speciation of iron (Fe) and the trace metals Cd, Cu, Co, Mn, Ni, and Zn were performed at four different locations in surface waters of the Baltic Sea. Measurements were performed during several months of the growth season at each station to obtain a detailed picture of the temporal variation in relation to phytoplankton growth. The main target was to understand the speciation of iron, and to evaluate if Fe was limiting in primary production. A methodological aim of the thesis...

  20. Adsorption of heavy metal by natural clayey soil


    Budianta, Wawan


    This study focused on the capability of Clayey soil to retain and release heavy metals. Batch experiment for sample of clayey soil was conducted with several concentrated solutions of heavy metals. The results show that the clayey soil sample may have a relatively high heavy metal retention capacity. This is particularly positive in the context of municipal waste disposal (landfills) in Indonesia Keywords: Adsorption, heavy metal, clayey soil, batch experiment

  1. Perilous Effects of Heavy Metals Contamination on Human Health


    Naseem Zahra; Imran Kalim; Minahil Mahmood; Nageen Naeem


    Heavy metals form a versatile group of high density elements that vary considerably in their biological roles and chemical properties. Although many heavy metals are essential trace elements yet they have long been recognized as environmental pollutants due their toxic effects. Increased industrialization, urbanization anthropogenic activities like mining, smelting and other agricultural activities have resulted in accumulation of heavy metals in the environment. Heavy metals such as nickel, ...

  2. Heavy Metal Concentrations in Maltese Potable Water

    Directory of Open Access Journals (Sweden)

    Roberta Bugeja


    Full Text Available This study evaluates the levels of aluminum (Al, cadmium (Cd, chromium (Cr, copper (Cu, iron (Fe, lead (Pb, nickel (Ni and zinc (Zn in tap water samples of forty localities from around the Maltese Islands together with their corresponding service supply reservoirs. The heavy metal concentrations obtained indicated that concentrations of the elements were generally below the maximum allowed concentration established by the Maltese legislation. In terms of the Maltese and EU water quality regulations, 17.5% of the localities sampled yielded water that failed the acceptance criteria for a single metal in drinking water. Higher concentrations of some metals were observed in samples obtained at the end of the distribution network, when compared to the concentrations at the source. The observed changes in metal concentrations between the localities’ samples and the corresponding supply reservoirs were significant. The higher metal concentrations obtained in the samples from the localities can be attributed to leaching in the distribution network.

  3. Technical development of geomicrobiological fixation of heavy metals in soils and sediments by biosorption and bioreduction -case histories in Korea (United States)

    Lee, Sung-Eun; Kim, Sang-Ho; Lee, Jong-Un; Chon, Hyo-Taek


    Conventional physicochemical technologies to remediate heavy metals-contaminated soil have many problems such as low efficiency, high cost and occurrence of byproducts. Recently biological stabilization technology is getting more and more attention. The advantage of this technology is that toxic metals can be stabilized for long time with no necessity of retreatment. The objective of this research is to develop geomicrobiological stabilization technologies of heavy metals by biosorption and oxidation/reduction in contaminated soil and sediment. Geochemical characteristics of heavy metals such as concentration and speciation in contaminated soil were investigated. Environmental conditions for effective biosorption were also investigated. It was successful to form biofilm in soil. Biofilm had great heavy metal biosorption capacity. Bioreduction efficiency of hexavalent chromium by indigenous bacteria was evaluated in various conditions.. From now on, it is necessary to prove applicability of this technologies to contaminated sites and to establish highly effective, low-cost and easy bioremediation technology.


    Directory of Open Access Journals (Sweden)

    Tetiana Bilyk


    Full Text Available Abstract. The main task was to investigate the pollution by heavy metals of biota of Vyrlytsa Lake. Thecontents of movable forms of heavy metals in aquatic plants, fish and snails was determined by atomicabsorbtion method and were made the conclusions about general state of the water object.Keywords: heavy metals, accumulation, biota, pollution, atomic absorption spectroscopy.

  5. Classification of Plants According to Their Heavy Metal Content ...

    African Journals Online (AJOL)

    Plants like other living organisms respond differently under different environmental conditions. An elevated level of heavy metals is one of the stresses which results into three classes of plants depending on their heavy metal content. The classes of plant species according to their accumulated heavy metals around North ...

  6. classification of plants according to their heavy metal content around

    African Journals Online (AJOL)


    ABSTRACT. Plants like other living organisms respond differently under different environmental conditions. An elevated level of heavy metals is one of the stresses which results into three classes of plants depending on their heavy metal content. The classes of plant species according to their accumulated heavy metals ...

  7. Heavy metals content in the stem bark of Detarium microcarpum ...

    African Journals Online (AJOL)

    The heavy metal analysis was carried out on the stem bark of D. microcarpum using an atomic absorption spectrophotometer (AAS). The heavy metals screened for include: lead, chromium, manganese, zinc and iron. The levels of manganese, zinc and iron were 13.91, 4.89 and 21.89 mg/L respectively. These heavy metals ...

  8. Absorption and bioaccumulation of heavy metals in giant African ...

    African Journals Online (AJOL)

    This study aimed at investigating the ability and effects (if any) of heavy metal accumulation in Giant African Land Snails (Archachatina marginata). 120 A. marginata growers were randomly allotted to 2 feed treatments (T1: Heavy metal contaminated pawpaw fruits and leaves; and T2: Heavy metal free pawpaw fruits and ...

  9. Studies of action of heavy metals on caffeine degradation by ...

    African Journals Online (AJOL)

    The isolate was encapsulated in gellan gum and its ability to degrade caffeine in the presence of heavy metals was determined. Out of the nine heavy metals tested, Copper (Cu), Mercury (Hg), and Silver (Ag) had significant effects on caffeine degradation at 1mg/L. Therefore, the concentration of these heavy metals was ...

  10. Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation (United States)

    Forgy, David


    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…

  11. incidence of heavy metals in kano metropolis drinking water sources ...

    African Journals Online (AJOL)


    into these sources as domestic sewage might be of kitchen and toilet origin heavily accumulated with soaps of heavy metals constituents. Heavy metal contamination with ... Water pollution has been a major challenge which requires ongoing evaluation. (Okonko et al., 2008).Presence of excessive amounts of heavy metals ...

  12. Bioaccumulation and toxic effects of some heavy metals in ...

    African Journals Online (AJOL)

    The contamination of the aquatic systems with heavy metals from natural anthropogenic sources has become a global problem which poses threats to ecosystems and natural communities. Hence this study reviews the effects of heavy metals in freshwater fishes. Fishes bioaccumulate heavy metals (including cadmium, zinc ...

  13. Customizable Biopolymers for Heavy Metal Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Kostal, Jan; Prabhukumar, Giridhar; Lao, U. Loi; Chen Alin; Matsumoto, Mark; Mulchandani, Ashok; Chen, Wilfred [University of California, Department of Chemical and Environmental Engineering (United States)], E-mail:


    Nanoscale materials have been gaining increasing interest in the area of environmental remediation because of their unique physical, chemical and biological properties. One emerging area of research has been the development of novel materials with increased affinity, capacity, and selectivity for heavy metals because conventional technologies are often inadequate to reduce concentrations in wastewater to acceptable regulatory standards. Genetic and protein engineering have emerged as the latest tools for the construction of nanoscale materials that can be controlled precisely at the molecular level. With the advent of recombinant DNA techniques, it is now possible to create 'artificial' protein polymers with fundamentally new molecular organization. The most significant feature of these nanoscale biopolymers is that they are specifically pre-programmed within a synthetic gene template and can be controlled precisely in terms of sizes, compositions and functions at the molecular level. In this review, the use of specifically designed protein-based nano-biomaterials with both metal-binding and tunable properties for heavy metal removal is summarized. Several different strategies for the selective removal of heavy metals such as cadmium and mercury are highlighted.

  14. Determination of heavy metals in the ambient atmosphere. (United States)

    Suvarapu, Lakshmi Narayana; Baek, Sung-Ok


    Heavy metal determination in ambient air is an important task for environmental researchers because of their toxicity to human beings. Some heavy metals (hexavalent chromium (Cr), arsenic (As), cadmium (Cd) and nickel (Ni)) have been listed as carcinogens. Furthermore, heavy metals in the atmosphere can accumulate in various plants and animals and enter humans through the food chain. This article reviews the determination of heavy metals in the atmosphere in different areas of the world since 2006. The results showed that most researchers concentrated on toxic metals, such as Cr, Cd, Ni, As and lead. A few studies used plant materials as bio-monitors for the atmospheric levels of heavy metals. Some researchers found higher concentrations of heavy metals surrounding industrial areas compared with residential and/or commercial areas. Most studies reported the major sources of the particulate matter and heavy metals in the atmosphere to be industrial emissions, vehicular emissions and secondary aerosols.

  15. Effect of heavy metals on bacterial transport (United States)

    Zhang, H.; Olson, M. S.


    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

  16. Origin and mobility of heavy metals in contaminated sediments from retention and infiltration ponds

    Energy Technology Data Exchange (ETDEWEB)

    Clozel, Blandine [BRGM - French Geological Survey, Service Geologique Regional, Rhone-Alpes, 151 Boulevard Stalingrad, 69626 Villeurbanne Cedex (France)]. E-mail:; Ruban, Veronique [Laboratoire Central des Ponts et Chaussees, Division Eau et Environnement, B.P. 4129, 44341 Bouguenais Cedex (France); Durand, Cedric [Laboratoire Central des Ponts et Chaussees, Division Eau et Environnement, B.P. 4129, 44341 Bouguenais Cedex (France); Conil, Pierre [BRGM - French Geological Survey, Service Geologique Regional, Pays de Loire, 1 rue des Saumonieres, B.P. 92342, 44323 Nantes Cedex 03 (France)


    The metal content of sediments from 4 ponds representative of contrasting environments and design was determined through speciation studies using both sequential chemical extraction and mineralogical observation. Surprisingly, the speciation for a given pond appears to be very homogenous, with the homogeneity being independent of total metal content, particle size or location within the pond. In contrast to what is commonly expected, no increase in metal content was found with decrease in size class. The proportion of metals in the different phases is distinct from one pond to another, reflecting distinct catchment areas. Contributions of alloys and atmospheric particles from industrial processes can be ascertained by SEM. Cadmium showed the highest availability in all 4 ponds with 40-60% extracted during the first step of the Community Bureau of Reference extraction scheme. Zinc, Pb and Cu, mostly sorbed on organic matter or oxides, may also become more mobile depending on physico-chemical changes. In France, an estimated volume of 5 million tons of sediment is extracted annually, and it is obvious that the risk, both environmental and human, associated with its heavy metal content and speciation cannot be totally ignored for the future use of this sediment.

  17. Electrodialytic remediation of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie


    Electrodialytic soil remediation is a method for removal of heavy metals. Good results have previously been obtained with both treatment of a stationary, water saturated soil matrix and with remediation of a stirred suspension of soil in water. The two different setups have different uses......). In the stirred setup it is possible to shorten the transport route to few mm and to have a faster and continuous process. The present paper for the first time reports a direct comparison of the two options. The remediation of the stirred suspension showed faster than remediation of the water saturated soil even...... without a short distance between the membranes. The acidification of the suspended soil was fastest and following the mobilization of heavy metals. This may indicate that water splitting at the anion exchange membrane is used more efficiently in the stirred setup....

  18. Distribution, speciation, and risk assessment of selected metals in the gold and iron mine soils of the catchment area of Miyun Reservoir, Beijing, China. (United States)

    Huang, Xingxing; Zhu, Yi; Ji, Hongbing


    In order to investigate the metal distribution, speciation, correlation and origin, risk assessment, 86 surface soil samples from the catchment area around the Miyun Reservoir, Beijing, including samples from gold and iron mine areas, were monitored for fractions of heavy metal and total contents. Most of the metal concentrations in the gold and iron mine soil samples exceeded the metal background levels in Beijing. The contents of most elements in the gold mine tailings were noticeably higher than those in the iron mine tailings. Geochemical speciation data of the metals showed that the residual fraction dominated most of the heavy metals in both mines. In both mine areas, Mn had the greatest the acid-soluble fraction (F1) per portion. The high secondary-phase fraction portion of Cd in gold mine samples indicated that there was a direct potential hazard to organisms in the tested areas. Multivariate analysis coupled with the contents of selected metals, showed that Hg, Pb, Cr, and Ni in gold mine areas represented anthropogenic sources; Cd, Pb, and Cr in iron mine areas represented industrial sources. There was moderate to high contamination of a few metals in the gold and iron soil samples, the contamination levels were relatively higher in gold mine than in iron mine soils.

  19. Phytoremediation of Heavy Metals in Aqueous Solutions


    Felix Aibuedefe AISIEN; Oluwole FALEYE; Eki Tina AISIEN


    One of the major environmental problems is the pollution of water and soil by toxic heavy metals. This study investigated the phytoremediation potential of water hyacinth, for the removal of cadmium (Cd), lead (Pb) and zinc (Zn). Water hyacinths were cultured in bore-hole water, supplemented with 5mg/l of Zn and Pb and 1mg/l of Cd at pH 4.5, 6.8 and 8.5. The plants were separately harvested each week for six weeks. The results showed that removal of these metals from solution was fast especia...

  20. Heavy metals in carabids (Coleoptera, Carabidae

    Directory of Open Access Journals (Sweden)

    Ruslan Butovsky


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

  1. Modeling Heavy Metal Removal in Wetlands. (United States)


    1976 a,b,c) and Pettersson (1976) treated heavy metals uptake according to Michaelis-Menten kinetics ( Lehninger , 1975), discussed later in detail...copper kinetics equation as used in this modeling effort is presented below, after Lehninger (1975): dv_ dV, Ca (5) dt dt C.+K, where: v = rate of copper...the bulk solution, Cb, using either the Lineweaver-Burk double reciprocal or Eadie-Hofstee graphical methods ( Lehninger , 1975). Nielsen (1976 b) used

  2. Sources, distribution, bioavailability, toxicity, and risk assessment of heavy metal(loid)s in complementary medicines. (United States)

    Bolan, Shiv; Kunhikrishnan, Anitha; Seshadri, Balaji; Choppala, Girish; Naidu, Ravi; Bolan, Nanthi S; Ok, Yong Sik; Zhang, Ming; Li, Chun-Guang; Li, Feng; Noller, Barry; Kirkham, Mary Beth


    The last few decades have seen the rise of alternative medical approaches including the use of herbal supplements, natural products, and traditional medicines, which are collectively known as 'Complementary medicines'. However, there are increasing concerns on the safety and health benefits of these medicines. One of the main hazards with the use of complementary medicines is the presence of heavy metal(loid)s such as arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg). This review deals with the characteristics of complementary medicines in terms of heavy metal(loid)s sources, distribution, bioavailability, toxicity, and human risk assessment. The heavy metal(loid)s in these medicines are derived from uptake by medicinal plants, cross-contamination during processing, and therapeutic input of metal(loid)s. This paper discusses the distribution of heavy metal(loid)s in these medicines, in terms of their nature, concentration, and speciation. The importance of determining bioavailability towards human health risk assessment was emphasized by the need to estimate daily intake of heavy metal(loid)s in complementary medicines. The review ends with selected case studies of heavy metal(loid) toxicity from complementary medicines with specific reference to As, Cd, Pb, and Hg. The future research opportunities mentioned in the conclusion of review will help researchers to explore new avenues, methodologies, and approaches to the issue of heavy metal(loid)s in complementary medicines, thereby generating new regulations and proposing fresh approach towards safe use of these medicines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Heavy metal emissions for Danish road transport

    Energy Technology Data Exchange (ETDEWEB)

    Winther, M.; Slentoe, E.


    This report presents new heavy metal emission factors for cars, vans, trucks, buses, mopeds and motorcycles for each of the emission sources fuel consumption, engine oil, tyre wear, brake wear and road abrasion. The emission components covered are Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pb), Selenium (Se) and Zinc (Zn), all of them relevant for emission reporting to the UNECE CLRTAP (United Nations Economic Commission for Europe Convention on Long Range Transboundary Pollutants) convention. The report also presents a new Danish inventory for the year 2007. The following emissions in total TSP (in brackets) are calculated for the year 2007: As (8 kg), Cd (48 kg), Cr (197 kg), Cu (51 779 kg), Hg (28 kg), Ni (158 kg), Pb (6 989 kg), Se (33 kg) and Zn (28 556 kg). Per vehicle type cars are the most important source of emission for all heavy metal species, followed by vans, trucks, buses and 2-wheelers. By using the detailed emission factors and inventory calculation methods established in the present project, estimates of heavy metal emissions can be made for other years than 2007. (author)

  4. Heavy Metals Acting as Endocrine Disrupters

    Directory of Open Access Journals (Sweden)

    Bogdan Georgescu


    Full Text Available Last years researches focused on several natural and synthetic compounds that may interfere with the major functionsof the endocrine system and were termed endocrine disrupters. Endocrine disrupters are defined as chemicalsubstances with either agonist or antagonist endocrine effects in human and animals. These effects may be achievedby interferences with the biosynthesis or activity of several endogenous hormones. Recently, it was demonstratedthat heavy metals such as cadmium (Cd, arsen (As, mercury (Hg, nickel (Ni, lead (Pb and zinc (Zn may exhibitendocrine-disrupting activity in animal experiments. Emerging evidence of the intimate mechanisms of action ofthese heavy metals is accumulating. It was revealed, for example, that the Zn atom from the Zn fingers of theestrogen receptor can be replaced by several heavy metal molecules such as copper, cobalt, Ni and Cd. By replacingthe Zn atom with Ni or copper, binding of the estrogen receptor to the DNA hormone responsive elements in the cellnucleus is prevented. In both males and females, low-level exposure to Cd interferes with the biological effects ofsteroid hormones in reproductive organs. Arsen has the property to bind to the glucocorticoid receptor thusdisturbing glucocorticoids biological effects. With regard to Hg, this may induce alterations in male and femalefertility, may affect the function of the hypothalamo-pituitary-thyroid axis or the hypothalamo-pituitary-adrenal axis,and disrupt biosynthesis of steroid hormones.

  5. [Research advances in heavy metals pollution ecology of diatom]. (United States)

    Ding, Teng-Da; Ni, Wan-Min; Zhang, Jian-Ying


    Diatom, due to its high sensitivity to environmental change, is one of the bio-indicators of aquatic ecosystem health, and some typical diatom species have been applied to indicate the heavy metals pollution of water body. With the focus on the surface water heavy metals pollution, this paper reviewed the research advances in the toxic effect of heavy metals pollution on diatom, biosorption and bioaccumulation of heavy metals by diatom, ecological adaptation mechanisms of diatom to heavy metals pollution, and roles of diatom as bio-indicator and in ecological restoration of heavy metals pollution. The growth tendency of diatom and the morphological change of frustule under heavy metals pollution as well as the differences in heavy metals biosorption and bioaccumulation by diatom, the ecological adaptation mechanisms of diatom on heavy metals surface complexation and ion exchange, and the roles of diatom as bio-indicator and in ecological restoration of heavy metals polluted water body were also discussed. This review could provide scientific evidences for the prevention of aquatic ecosystems heavy metals pollution and related early warning techniques.

  6. Removal of heavy metals from wastewater using electrocoagulation


    Pokhrel, Nikunj


    Heavy metal contamination of water sources is a constant threat to human health. High exposure of heavy metals have often resulted in severe health hazards such as cancer, growth deficiency, liver and kidney damage and in some extreme cases death (World Health Organization, 2005). Heavy metals are often released into the environment and mainly into the water sources in the form of industrial and municipal wastewater. This thesis aims at examining the possibility of removing 5 different heavy ...

  7. Phytoremediation of Heavy Metals in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Felix Aibuedefe AISIEN


    Full Text Available One of the major environmental problems is the pollution of water and soil by toxic heavy metals. This study investigated the phytoremediation potential of water hyacinth, for the removal of cadmium (Cd, lead (Pb and zinc (Zn. Water hyacinths were cultured in bore-hole water, supplemented with 5mg/l of Zn and Pb and 1mg/l of Cd at pH 4.5, 6.8 and 8.5. The plants were separately harvested each week for six weeks. The results showed that removal of these metals from solution was fast especially in the first two weeks, after which it became gradual till saturation point was reached. The accumulation of Cd and Zn in leaves and roots increased with increase in pH. The highest accumulation was in the roots with metal concentration of 4870mg/kg, 4150mg/kg and 710mg/kg for Zn, Pb and Cd respectively at pH 8.5. The maximum values of bioconcentration factor (BCF for Zn, Pb and Cd were 1674, 1531 and 1479 respectively, suggesting that water hyacinth was good accumulator of Zn, Pb and Cd, and could be used to treat industrial wastewater contaminated with heavy metals such as Zn, Pb and Cd.

  8. Assessment of Heavy Metal Pollution in Sediment and Polychaete ...

    African Journals Online (AJOL)

    HEAVY METAL POLLUTION & POLYCHAETE WORMS FROM MZINGA CREEK & RAS DEGE MANGROVE ECOSYSTEM. 125 ... metal pollution. The concentration of metals in the geochemically available sediment fraction (easily reducible and oxidisable phases) is analysed to assess the ..... River inputs to the ocean.

  9. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution (United States)

    Pujol, Luca; Evrard, David; Groenen-Serrano, Karine; Freyssinier, Mathilde; Ruffien-Ciszak, Audrey; Gros, Pierre


    A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic “on line” monitoring devices are also evoked.

  10. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution

    Directory of Open Access Journals (Sweden)

    Luca ePUJOL


    Full Text Available A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic on line monitoring devices are also evoked.

  11. Contamination and fractionation of heavy metals in bedload sediments of the Siahrood River (Qaem-Shar area-Mazandaran Province

    Directory of Open Access Journals (Sweden)

    Shima Rostami


    Full Text Available The main objective of the present study is to evaluate variation, contamination and speciation of heavy metals in bed sediments of the Siahrood River in Mazandaran Province. For this purpose, fifteen sediment samples were collected along the main channel of the river. In addition to total content of heavy metals and selected physiochemical properties of the sediments, geochemical species of heavy metals were determined operationally using the modified BCR method. The obtained results generally showed that there is a wide variation in heavy metal concentrations in the sediments, probably due to anthropogenic inputs into the river and effect of physicochemical properties of the sediments (organic matter and clay content on the heavy metals variability. The calculated Igeo (Geo-accumulation index for each metal also revealed that sediments are moderately or strongly contaminated in terms of Pb and Cd whereas not or slightly contaminated with respect to other heavy metals, suggesting an anthropogenic source for Pb and Cd and a mostly geogenic origin for Ni, Zn, and Cr (Arsenic is probably of a mixed source. The results of BCR method indicated that Pb and Cd are predominately incorporated into the first fraction (F1, acid-soluble fraction while Zn and Ni are mainly associated with residual fraction (F4 confirming the concluded remarks on discrimination of heavy metals origins in the sediments.

  12. Material Removes Heavy Metal Ions From Water (United States)

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


    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.

  13. Magnetotactic bacteria. Promising biosorbents for heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Wei; Zhang, Yanzong; Ding, Xiaohui; Liu, Yan; Shen, Fei; Zhang, Xiaohong; Deng, Shihuai; Xiao, Hong; Yang, Gang; Peng, Hong [Sichuan Agricultural Univ., Chengdu (China). Provincial Key Lab. of Agricultural Environmental Engineering


    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. (orig.)

  14. Effects of Heavy Metal Toxicity on Human Health


    Guluzar Ozbolat; Abdullah Tuli


    Heavy metals are the elements that can be toxic even at low concentrations. It is often used as a group name for metals and semimetals (metalloids) that have been associated with contamination and potential toxicity or ecotoxicity. Heavy metals are toxic to human health. Because it cannot be discarded with (kidney, liver intestine, skin, lung) without special support from most of the body's normal excretion routes Therefore, a large part of the heavy metals accumulate in biological organisms...

  15. Heavy Metals Distribution and Speciation in Soils around a Mega ...

    African Journals Online (AJOL)

    ... Mn and Fe are mainly of natural origin. Pb was found to be the most mobile with mobility factor of 71.8% while Fe has the least mobility factor of 3.62%. Regression analysis (r2 = 0.71) further showed that Cu is correlated with Pb. Soil pollution indices revealed that the surface soil is slightly contaminated in lead and zinc, ...

  16. Speciation And Mobility Study Of Selected Heavy Metals In Kofe ...

    African Journals Online (AJOL)

    Variation among obtained results, i.e., %MF and concentration of analytes, were evaluated using one way ANOVA at (P<0.05). It was observed that Cd and Pb exhibited vertical mobility and thus could lead to pollution of the underground water. Similarly, the highest amount of Pb in the bioavailable fraction may also indicate ...

  17. Heavy metal and associated antibiotic resistance of fecal coliforms ...

    African Journals Online (AJOL)

    Objective: The pollution of the environment with toxic heavy metals is increasing globally with industrial progress. Microorganisms can be good bio-accumulators of particulate and soluble forms of heavy metals and subsequently resist antibiotics. The present study aimed at assessing the resistance pattern to multiple heavy ...

  18. Advances in Understanding How Heavy Metal Pollution Triggers Gastric Cancer

    Directory of Open Access Journals (Sweden)

    Wenzhen Yuan


    Full Text Available With the development of industrialization and urbanization, heavy metals contamination has become a major environmental problem. Numerous investigations have revealed an association between heavy metal exposure and the incidence and mortality of gastric cancer. The mechanisms of heavy metals (lead, cadmium, mercury, chromium, and arsenic contamination leading to gastric cancer are concluded in this review. There are four main potential mechanisms: (1 Heavy metals disrupt the gastric mucosal barrier by decreasing mucosal thickness, mucus content, and basal acid output, thereby affecting the function of E-cadherin and inducing reactive oxygen species (ROS damage. (2 Heavy metals directly or indirectly induce ROS generation and cause gastric mucosal and DNA lesions, which subsequently alter gene regulation, signal transduction, and cell growth, ultimately leading to carcinogenesis. Exposure to heavy metals also enhances gastric cancer cell invasion and metastasis. (3 Heavy metals inhibit DNA damage repair or cause inefficient lesion repair. (4 Heavy metals may induce other gene abnormalities. In addition, heavy metals can induce the expression of proinflammatory chemokine interleukin-8 (IL-8 and microRNAs, which promotes tumorigenesis. The present review is an effort to underline the human health problem caused by heavy metal with recent development in order to garner a broader perspective.

  19. The Confluence of Heavy Metal Biooxidation and Heavy Metal Resistance: Implications for Bioleaching by Extreme Thermoacidophiles

    Directory of Open Access Journals (Sweden)

    Garrett Wheaton


    Full Text Available Extreme thermoacidophiles (Topt > 65 °C, pHopt < 3.5 inhabit unique environments fraught with challenges, including extremely high temperatures, low pH, as well as high levels of soluble metal species. In fact, certain members of this group thrive by metabolizing heavy metals, creating a dynamic equilibrium between biooxidation to meet bioenergetic needs and mechanisms for tolerating and resisting the toxic effects of solubilized metals. Extremely thermoacidophilic archaea dominate bioleaching operations at elevated temperatures and have been considered for processing certain mineral types (e.g., chalcopyrite, some of which are recalcitrant to their mesophilic counterparts. A key issue to consider, in addition to temperature and pH, is the extent to which solid phase heavy metals are solubilized and the concomitant impact of these mobilized metals on the microorganism’s growth physiology. Here, extreme thermoacidophiles are examined from the perspectives of biodiversity, heavy metal biooxidation, metal resistance mechanisms, microbe-solid interactions, and application of these archaea in biomining operations.

  20. Heavy metals bioaccumulation by edible saprophytic mushrooms

    Directory of Open Access Journals (Sweden)

    Ivan ŠIRIĆ


    Full Text Available The aim of this study was to determine the concentration of heavy metals Fe, Zn, Cu, Ni, Pb i Cd in certain edible species of saprophytic fungi and the substrate on three area of sampling, and to assess the role of individual species as biological indicators of environmental pollution. In this study were used three species of wild edible mushrooms (Agaricus macroarpus Bohus, Clitocybe inversa (Scop. ex Fr. Pat. and Macrolepiota procera (Scop. ex Fr. Sing.,. Completely developed and mature fruiting bodies were collected at random selection in localities of Trakošćan, Jaska and Petrova gora. At the same time, the substrate soil samples were collected from the upper horizon (0-10. Determination of heavy metals in mushrooms and the substrate soil were carried out by X-ray Fluorescence Spectrometry. The data obtained were analysed by means of the statistical program SAS V9.2. Significant differences were found in the concentrations of Fe, Zn, Cu, Ni, Pb and Cd between analysed species of mushrooms and localities of sampling (P 1. The consumption of investigated mushrooms poses no toxicological risk to human health due to low concentrations analysed metals.

  1. Interactions between humic acid and hematite and their effects on metal ion speciation

    NARCIS (Netherlands)

    Vermeer, A.W.P.


    The impact of toxic chemicals (like metal ions) on the environment is a phenomenon that has been recognised as a mayor problem over the last decades. The speciation of these chemicals determines whether or not a contaminated site has to be regarded as dangerous. The fate of the

  2. Comparison of analytical techniques for dynamic trace metal speciation in natural freshwaters

    NARCIS (Netherlands)

    Sigg, L.; Black, F.; Buffle, J.; Cao, J.; Cleven, R.; Davison, W.; Galceran, J.; Gunkel, P.; Kalis, E.J.J.; Kistler, D.; Martin, M.; Noel, S.; Nur, Y.; Odzak, N.; Puy, J.; Riemsdijk, van W.H.; Temminghoff, E.J.M.; Tercier-Waeber, M.L.; Toepperwien, S.; Town, R.M.; Unsworth, E.R.; Warnken, K.W.; Weng, L.P.; Xue, H.B.; Zhang, H.


    Several techniques for speciation analysis of Cu, Zn, Cd, Pb, and Ni are used in freshwater systems and compared with respect to their performance and to the metal species detected. The analytical techniques comprise the following: (i) diffusion gradients in thin-film gels (DGT); (ii) gel integrated

  3. Heavy Metal Contents of Lake Sapanca


    YALÇIN, Nevin; SEVİNÇ, Vahdettin


    The heavy metal pollution of Lake Sapanca located in the Marmara region (Turkey), was investigated over time. The lake is the drinking water source of the city of Adapazarı and its environs. The D-80 (TEM) motorway passes about 5 km along the lake's zero point in the Sapanca district. The motorway's wastewater drainages have been connected to the lake without having been subjected to any wastewater treatment. The motorway was opened to service in October 1990. An...

  4. Evaluation of heavy metal complex phytotoxicity

    Directory of Open Access Journals (Sweden)

    Vita Vasilyevna Datsenko


    Full Text Available The experimental data dealing with the effect of heavy metals contained in the technogenic contaminated soils on plant objects under controlled conditions was discussed. The aim of this work is to define the quantitative indicators of copper and zinc potential phytotoxicity, namely germination energy, simultaneous germination and duration of the test plants. It was found that the activity of the test plant growth is linked with copper and zinc complex action. Joint effect of copper and zinc is manifested both in inhibition of lettuce growth and determined, above all, by the nature contamination, soil properties and biological specificity of the test plants.

  5. Assessment of Heavy Metal Contamination in Soils around Cassava ...

    African Journals Online (AJOL)

    Assessment of Heavy Metal Contamination in Soils around Cassava Processing Mills in Sub- Urban Areas of Delta State, Southern Nigeria. ... The percent anthropogenic fraction of metals in the soil follow the order Cd > Zn > Ni > Cu > Fe > Cr > Pb. Keywords: Anthropogenic input, cassava, heavy metals, pollution index ...

  6. Heavy metal ion uptake properties of polystyrene-supported ...

    Indian Academy of Sciences (India)


    at pH 6 they are found to be Cd(II) and Cr(VI) selective. Metal ion uptake properties of resins follow Freundlich's equation. The resins are recyclable and are therefore employed for the removal of heavy metal pollutants from industrial waste water. Keywords. Uptake properties; heavy metal ion; selectivity; recyclability. 1.

  7. Determination of heavy metals in water sediments and Tilapia zilli ...

    African Journals Online (AJOL)

    The study investigated the heavy metal concentration in Tilapia zilli and water sediments along Kolo Creek in Ogbia Local Government Area, Bayelsa State. Tilapia fish and sediment samples were collected from 5 stations, and analyzed for heavy metals following standard procedures. Four metals (Copper, Lead. Cadmium ...

  8. Assessment and bioremediation of heavy metals from crude oil ...

    African Journals Online (AJOL)

    The assessment of the levels of heavy metals present in crude oil contaminated soil and the application of the earthworm - Hyperiodrilus africanus with interest on the bioremediation of metals from the contaminated soil was investigated within a 90-days period under laboratory conditions. Selected heavy metals such as ...

  9. Heavy metals occurrence in Italian food supplements

    Directory of Open Access Journals (Sweden)

    Brizio P.


    Full Text Available In recent years a significant increase in food supplements consumption has been observed, maybe in the belief that they couldn’t be dangerous for consumers health, even if they don’t achieved medical effects. However, environmental pollution can cause heavy metals contamination that could exceed maximum levels established by European legislation. Aim of this work was to evaluate arsenic, cadmium, chromium, lead and mercury content in 12 food supplements seized in a Piedmont shop by the Italian authority against food adulteration. All metals were analysed after mineralization and dilution steps by ICP-MS, with the exception of mercury, detected by the direct analyser TDA-AAS. Only one sample exceed the European maximum limits for lead (3,00 mg/kg but warning levels of chromium (over 3,00 mg/Kg has been detected in three of them.

  10. Atmospheric heavy metal deposition in Europe estimated by moss analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ruehling, Aa. [Swedish Environmental Research Inst., Lund (Sweden). Dept. of Ecology


    Atmospheric heavy metal deposition in Europe including 21 countries was monitored in 1990-1992 by the moss technique. This technique is based on the fact that the concentrations of heavy metals in moss are closely correlated to atmospheric deposition. This was the first attempt to map heavy metal deposition in this large area. The objectives of the project were to characterise qualitatively and quantitatively the regional atmospheric deposition pattern of heavy metals in background areas in Europe, to indicate the location of important heavy metal pollution sources and to allow retrospective comparisons with similar studies. The present survey is a follow-up of a joint Danish and Swedish project in 1980 and an extended survey in 1985 within the framework of the Nordic Council of Ministers. In Sweden, heavy-metal deposition was first mapped on a nation-wide scale in 1968-1971 and 1975. (author)

  11. Effect of heavy metal and EDTA application on heavy metal uptake ...

    African Journals Online (AJOL)

    The present study investigates the effect of different concentration of heavy metals (Cd, Cr and Pb) and ethylenediaminetetraacetic acid (EDTA) application on two Brassica species (Brassica carinata and Brassica juncea). EDTA application had significant (p<0.05) effect on shoot length, shoot fresh weight, shoot dry weight, ...

  12. Characteristics of heavy metal pollution on roadside soil along highway (United States)

    Zheng, Chaocheng


    Highway traffic is the main source of heavy metal pollution. Due to limited cropland, it is very common to plant crops along the highways. So, in view of agricultural products safety, heavy metal pollution by highway traffic to soils along highway is widely concerned. Therefore, to study distribution traits, accumulative laws and influence factors of heavy metals in agricultural soils could provide scientific evidence and theoretical basis for environmental protection along express way.

  13. Heavy Metal Induced Antibiotic Resistance in Bacterium LSJC7


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


    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...

  14. Impact of heavy metals on the female reproductive system


    Piotr Rzymski; Katarzyna Tomczyk; Pawel Rzymski; Barbara Poniedziałek; Tomasz Opala; Maciej Wilczak


    Introduction. It has been recognized that environmental pollution can affect the quality of health of the human population. Heavy metals are among the group of highly emitted contaminants and their adverse effect of living organisms has been widely studied in recent decades. Lifestyle and quality of the ambient environment are among these factors which can mainly contribute to the heavy metals exposure in humans. Objective. A review of literature linking heavy metals and the female repr...

  15. Effects of heavy metal adsorption on silicene

    KAUST Repository

    Kaloni, Thaneshwor P.


    Based on first-principles calculations, we study the effects of heavy metal atoms (Au, Hg, Tl, and Pb) adsorbed on silicene. We find that the hollow site is energetically favorable in each case. We particulary address the question how the adsorption modifies the band structure in the vicinity of the Fermi energy. Our results demonstrate that the heavy metal adatoms result in substantial energy gaps and band splittings in the silicene sheet as long as the binding is strong, which, however, is not always the case. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) Carbon nanotube flexible sponge was manufactured as high performance electromagnetic shielding material. Chemical vapour deposition (CVD) synthesized sponges with extreme light weight show an electromagnetic shielding above 20 dB and a specific electromagnetic shielding as high as 1100 dB cm3g-1 in the whole 1-18 GHz range. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Remediation of biochar on heavy metal polluted soils (United States)

    Wang, Shuguang; Xu, Yan; Norbu, Namkha; Wang, Zhan


    Unreasonable mining and smelting of mineral resources, solid waste disposal, sewage irrigation, utilization of pesticides and fertilizers would result in a large number of heavy metal pollutants into the water and soil environment, causing serious damage to public health and ecological safety. In recent years, a majority of scholars tried to use biochar to absorb heavy metal pollutants, which has some advantages of extensive raw material sources, low-cost and high environmental stability. This paper reviewed the definition, properties of biochar, the mechanism of heavy metal sorption by biochar and some related problems and prospects, to provide some technical support for the application of biochar into heavy metal polluted soils.

  17. Adsorption of heavy metal in freeway by asphalt block (United States)

    Zheng, Chaocheng


    Heavy metals are toxic, persistent, and carcinogenic in freeway. Various techniques are available for the removal of heavy metals from waste water among soils during freeway including ion-exchange, membrane filtration, electrolysis, coagulation, flotation, and adsorption. Among them, bio-sorption processes are widely used for heavy metal and other pollutant removal due to its sustainable, rapid and economic. In this paper, heavy metal removal facilitated by adsorption in plants during freeway was illustrated to provide concise information on exploring the adsorption efficiency.

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


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


    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 li...

  19. Kinetic and thermodynamic determinants of trace metal partitioning at biointerphases: the role of intracellular speciation dynamics. (United States)

    Duval, Jérôme F L; Présent, Romain M; Rotureau, Elise


    There is a large body of work evidencing the necessity to evaluate chemical speciation dynamics of trace metals in solution for an accurate definition of their bioavailability to microorganisms. In contrast, the integration of intracellular metal speciation dynamics in biouptake formalisms is still in its early stages. Accordingly, we elaborate here a rationale for the interplay between chemodynamics of intracellular metal complexes and dynamics of processes governing metal biouptake under non-complexing outer medium conditions. These processes include the conductive diffusion of metal ions to the charged soft biointerphase, metal internalisation, excretion of intracellular free metal species and metal depletion from bulk solution. The theory is formulated from Nernst-Planck equations corrected for electrostatic and reaction kinetic terms applied at the biosurface and in the intracellular volume. Computational illustrations demonstrate how biointerfacial metal distribution dynamics inherently reflects the chemodynamic properties of intracellular complexes. In the practical limits of high and weak metal affinity to biosurface internalisation sites, the metal concentration profile is explicitly solved under conditions of strong intracellular complexing agents. Exact analytical expression is further developed for metal partitioning at equilibrium. This provides a way to evaluate the metal biopartition coefficient from refined analysis of bulk metal depletion measured at various cell concentrations. Depending on here-defined dimensionless parameters involving rates of metal internalisation-excretion and complex formation, the formalism defines the nature of the different kinetic regimes governing bulk metal depletion and biouptake. In particular, the conditions leading to an internalisation flux limited by diffusion as a result of demanding intracellular metal complexation are identified.

  20. Changes in heavy metal mobility and availability from contaminated wetland soil remediated with combined biochar-compost. (United States)

    Liang, Jie; Yang, Zhaoxue; Tang, Lin; Zeng, Guangming; Yu, Man; Li, Xiaodong; Wu, Haipeng; Qian, Yingying; Li, Xuemei; Luo, Yuan


    The combination of biochar and compost has been proven to be effective in heavy metals contaminated wetland soil restoration. However, the influence of different proportions between biochar and compost on immobilization of heavy metals in soil has been less studied up to date. Therefore, we investigated the effect of different ratios of biochar-compost mixtures on availability and speciation distribution of heavy metals (Cd, Zn and Cu) in wetland soil. The results showed that applying all amendment combinations into wetland soil increased gradually the total organic carbon (TOC) and water-extract organic carbon (WEOC) as the compost percentage rose in biochar-composts. The higher pH was obtained in a certain biochar addition (20% and 40%) in combinations due to efficient interaction of biochar with compost. All amendments could significantly decrease availability of Cd and Zn mainly from pH change, but increase available Cu concentration as the result of increased water-extract organic carbon and high total Cu content in compost. Moreover, amendments can decrease easily exchangeable fraction and increase reducible of Cd and Zn greatly with increase of compost content in combinations, while amendments containing compost promote transformation of Cu from Fe/Mn oxide and residual fractions to organic bindings. These results demonstrate that different ratios of biochar and compost have a significant effect on availability and speciation of heavy metals in multi-metal-contaminated wetland soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Mineralogy and metals speciation in Mo rich mineral sludges generated at a metal recycling plant. (United States)

    Vemic, M; Bordas, F; Guibaud, G; Joussein, E; Labanowski, J; Lens, P N L; van Hullebusch, E D


    In France, more than 250 million metric tons of sludges need to be treated each year. These sludges are either dumped on the landfills or reused as secondary resources in order to preserve natural resources. A large portions of these sludges are mineral sludges, originating from metal recycling plants. In order to estimate their metal recovery potential, these mineral sludges were characterized. Four types of mineral sludge samples were collected from a metal recycling plant (3 from the recycling plant storage areas (bulk storage, barrel storage and storage shed) and 1 from the collection basin). The sludges were characterized, wherein the Mo, Ni, Cr, Co, Zn and W content and speciation were quantified. The samples had pH values between 5.9 and 10.3 with organic matter contents varying between 6.3% (storage shed) and 29.5% (bulk storage) (loss on ignition at 500 °C). Based on their leaching properties, the four mineral sludge samples (in the case of Mo) and the bulk storage sludge (in the case of Ni and Zn) were classified as potentially hazardous regarding the EN 12457-1 and EN 12457-2 method. Mineralogical results reveal that both bulk storage and the storage shed give the highest contributions to the metal content of the collection basin sample. Sequential extraction of the collection basin samples indicated that Mo is bound to the oxidizable and residual fraction, while Ni, Cr and Co were bound to the residual fraction, and Zn to the soluble acid fraction, respectively. W tends to be equally distributed among all extracted fractions. A strong correlation existed between Mo and Co, as well as between Ni, Zn and Cr, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Remediation of heavy metal contaminated soil | Nanda | African ...

    African Journals Online (AJOL)

    This paper investigates the plant-microbial interactions in reclaiming the metal contaminated soil with attention to some significant soil biochemical characteristics during the process. Keywords: Heavy metals, bioremediation, phytoremediation, rhizosphere, rhizobacteria, bioaugmentation. African Journal of Biotechnology ...

  3. Phytoremediation of heavy metals roadside contaminated soil using ...

    African Journals Online (AJOL)

    Computing Services


    Oct 23, 2013 ... E. camaldeulensis. This suggests that E. camaldeulensis was the best candidate species for phytoremediation of HM contaminated soils. Key words: Keywords: Phytoextraction, Roadside soil, Heavy metal, ... production, construction, vehicle exhaust, waste disposal, ... Unlike organic pollutants, metals.

  4. Effect of heavy metals on enzymes production by Hebeloma crustuliniforme

    Directory of Open Access Journals (Sweden)

    Hanna Dahm


    Full Text Available Studies were carried out in order to dętermine the effect of some heavy metals (Cu, Cd, Pb, Zn on the production of enzymes (cellulases, peetinases. proteases by ectomycorrhizal fungus Hebeloma crusliliniforme (Buli.: Fr. Quél. All the heavy metals inhibited the general enzymatic activity regardless of the source of carbon used. The metals reduced the egzocellulolytic activity more in media with cellulose powder than with CMC (carboxymethylocellulosc. Among pectolytic enzymes heavy metals most strongly inhibited polygalacturonase (PG. The heavy metals did not harmful affect the activity of pectate lyase (PGL. Proteolytic activity of Hebeloma crustuliniforme was leasi affected by zinc (Zn. The degree of inhibition of enzymes by heavy metals can be presented in the following order Pb < Zn < Cd

  5. Heavy Metal Induced Antibiotic Resistance in Bacterium LSJC7. (United States)

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


    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.

  6. Gold-functionalized DNAzyme Nanosensors to Quantify Heavy Metal Gradients (United States)

    Adriaens, P.; Vannela, R.


    The presence of heavy metals in environmental systems is characterized by steep gradients due to the presence of solid and soluble redox species. The capability to selectively quantify low concentrations of individual redox species continues to present a challenge for site characterization and risk assessment. Recently, DNAzymes, single-stranded DNA molecules with catalytic capabilities that are isolated from random-sequence DNA libraries by ``in vitro selection'', have come to the fore as unique molecular tools for metal detection in aqueous environment. Here we describe the selection and characterization of an RNA-cleaving autocatalytic DNAzyme that links chemical catalysis with real-time fluorescence signaling in the single molecule. From a random pool of 40-nt templates, we have isolated Hg-active DNAzymes using in vitro selection procedures in combination with non-homologous random recombination (NRR). However, significant cleavage was seen for DNA sequences isolated in generation G5. By G8 cycle, more than 32% of the DNA construct was cleaved after 3-h incubation. After eight rounds of selection and amplification, the amount of eluted DNA after respective reaction was found to produce active sequences leading to 32 % catalysis. The introduction of nonhomologous random recombination at 9th cycle yielded drastic increase in catalysis to 55% of the total oligonucleotide pool. DNA sequences from the 9th round of selection (G9) were amplified by PCR and cloned into a vector. DNA sequencing was performed and the M-fold software revealed variety of different families of sequences in the active pool - with DNA-010 sequence being dominant in each family. Similar experiments conducted with As5+ and selection did not show any cleavage until the 8th cycle, with cleavage increasing to 18 % at 14th cycle. Since the catalytic activity can be characterized in terms of metal specificity, speciation and affinity, the catalytic DNA serves as a sensor for a variety of metal ion

  7. The occurrence of heavy metals in irrigated and non-irrigated arable soils, NW Albania. (United States)

    Kasa, Elian; Felix-Henningsen, Peter; Duering, Rolf-Alexander; Gjoka, Fran


    The study analysed the content of heavy metals in surface soil and sediment samples from the Bregu i Matit Plain in NW Albania in relation to irrigation in order to evaluate the soil pollution and the potential risk to human health. Evaluation of soil pollution was performed using the enrichment factor and geo-accumulation index. Contents of cadmium, chromium and nickel of irrigated soils were significantly higher than those of non-irrigated soil, while contents of lead (in three of the irrigated locations), zinc and arsenic (in one of the irrigated locations) were significantly lower. Correlation analysis (CA) and principal component analysis (PCA) indicated that the primary source of the first three metals was irrigation, and the last three metals were originated from other anthropic sources, like the use of chemicals, etc. Enrichment factor (E f) calculation showed that irrigated soils were most enriched in cadmium, chromium, copper and nickel. Index of geo-accumulation (I geo) revealed that arable soils of Bregu i Matit are unpolluted to moderately polluted with cadmium, chromium, copper and zinc and moderately to strongly polluted with nickel and arsenic. The presence of heavy metals in the studied soils indicates a potential risk of transfer of these elements in the food chain. Therefore, further studies on the speciation of heavy metals in the studied soils in order to evaluate their mobility are needed.

  8. Thermal Characteristics of Hyperaccumulator and Fate of Heavy Metals during Thermal Treatment of Sedum plumbizincicola. (United States)

    Zhong, Daoxu; Zhong, Zhaoping; Wu, Longhua; Xue, Hui; Song, Zuwei; Luo, Yongming


    Thermal treatment is one of the most promising disposal techniques for heavy metal- (HM)-enriched hyperaccumulators. However, the thermal characteristics and fate of HMs during thermal treatment of hyperaccumulator biomass need to be known in detail. A horizontal tube furnace was used to analyze the disposal process of hyperaccumulator biomass derived from a phyto-extracted field in which the soil was moderately contaminated with heavy metals. Different operational conditions regarding temperature and gas composition were tested. A thermo-dynamic analysis by advanced system for process engineering was performed to predict HM speciation during thermal disposal and SEM-EDS, XRD and sequential chemical extraction were used to characterize the heavy metals. The recovery of Zn, Pb and Cd in bottom ash decreased with increasing temperature but recovery increased in the fly ash. Recovery of Zn, Pb and Cd fluctuated with increasing air flow rate and the metal recovery rates were higher in the fly ash than the bottom ash. Most Cl, S, Fe, Al and SiO2 were found as alkali oxides, SO2, Fe2(SO4)3, iron oxide, Ca3Al2O6, K2SiO3 and SiO2 instead of reacting with HMs. Thus, the HMs were found to occur as the pure metals and their oxides during the combustion process and as the sulfides during the reducing process.

  9. Hydroponic phytoremediation of heavy metals and radionuclides

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  10. Heavy metals biogeochemistry in abandoned mining areas

    Directory of Open Access Journals (Sweden)

    Favas P. J. C.


    Full Text Available Plants growing on the abandoned Portuguese mines, highly contaminated with W, Sn, As, Cd, Cu, Zn and Pb, have been studied for their biogeochemical indication/prospecting and mine restoration potential. The results of analysis show that the species best suited for biogeochemical indicating are: aerial tissues of Halimium umbellatum (L. Spach, for As and W; leaves of Erica arborea L. for Bi, Sn, W and mostly Pb; stems of Erica arborea L. for Pb; needles of Pinus pinaster Aiton and aerial tissues of Pteridium aquilinum (L. Kuhn for W; and leaves of Quercus faginea Lam. for Sn. The aquatic plant studied (Ranunculus peltatus Schrank can be used to decrease the heavy metals, and arsenic amounts into the aquatic environment affected by acid mine drainages.

  11. Effects of aerobic and anaerobic biological processes on leaching of heavy metals from soil amended with sewage sludge compost. (United States)

    Fang, Wen; Wei, Yonghong; Liu, Jianguo; Kosson, David S; van der Sloot, Hans A; Zhang, Peng


    The risk from leaching of heavy metals is a major factor hindering land application of sewage sludge compost (SSC). Understanding the change in heavy metal leaching resulting from soil biological processes provides important information for assessing long-term behavior of heavy metals in the compost amended soil. In this paper, 180days aerobic incubation and 240days anaerobic incubation were conducted to investigate the effects of the aerobic and anaerobic biological processes on heavy metal leaching from soil amended with SSC, combined with chemical speciation modeling. Results showed that leaching concentrations of heavy metals at natural pH were similar before and after biological process. However, the major processes controlling heavy metals were influenced by the decrease of DOC with organic matter mineralization during biological processes. Mineralization of organic matter lowered the contribution of DOC-complexation to Ni and Zn leaching. Besides, the reducing condition produced by biological processes, particularly by the anaerobic biological process, resulted in the loss of sorption sites for As on Fe hydroxide, which increased the potential risk of As release at alkaline pH. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Factors Affecting the Binding of a Recombinant Heavy Metal-Binding Domain (CXXC motif) Protein to Heavy Metals


    Kamala Boonyodying; Thanakorn Watcharasupat; Waranan Yotpanya; Thawatchai Kitti; Wanna Kawang; Duangkamol Kunthalert; Sutthirat Sitthisak


    A number of heavy metal-binding proteins have been used to study bioremediation. CXXC motif, a metal binding domain containing Cys-X-X-Cys motif, has been identified in various organisms. These proteins are capable of binding various types of heavy metals. In this study, heavy metal binding domain (CXXC motif) recombinant protein encoded from mcsA gene of S. aureus were cloned and overexpressed in Escherichia coli. The factors involved in the metal-binding activity were determined in order to...

  13. X-ray fluorescence spectroscopic determination of heavy metals and ...

    African Journals Online (AJOL)

    Purpose: To determine the heavy metal and trace element composition of the powdered aerial parts of Origanum sipyleum L. and its water extract. Methods: The heavy metal and trace elements content of the powdered plant material and 2 % aqueous extract were evaluated by x-ray fluorescence spectroscopy with silicon ...

  14. Assessment of heavy metals in Lake Uluabat, Turkey | Elmaci ...

    African Journals Online (AJOL)

    The accumulation of heavy metals (Cu, Ni, Zn, Cd, Pb, Cr, B, As) was measured in water, plankton and sediment samples taken from different areas of Lake Uluabat during January 2003 to February 2004. The sequential extraction used in this study is useful to assess the potential mobility of heavy metals in the sediment ...

  15. Bioaccumulation of Heavy Metals by Moringa Oleifera in Automobile ...

    African Journals Online (AJOL)

    Plants accumulate minerals essential for their growth from the environment alongside with heavy metals from contaminated areas.This study investigated bioaccumulation of heavy metals by Moringa oleifera in automobile workshops in three selected local government areas in Ibadan. This was done with a view to ...

  16. Sediment-Water Exchange of Selected Heavy Metals at the ...

    African Journals Online (AJOL)

    Organic matter oxidation contributed to the mobilization of heavy metals, demonstrating the significant effect of atmospheric oxidation on heavy metals dynamics at the Makupa creek backwaters during low tide. Humic and fluvic acid mobilization did not have a significant effect in the mobilization of Fe (Pearson correlation ...

  17. Heavy Metals Pollution on Surface Water Sources in Kaduna ...

    African Journals Online (AJOL)

    Heavy Metals Pollution on Surface Water Sources in Kaduna Metropolis, Nigeria. JA Aliyu, Y Saleh, S Kabiru. Abstract. This study examine the effects of heavy metal pollutants to aquatic ecosystems and the environment by considering the role of urban, municipal, agricultural, industrial and other anthropogenic processes ...

  18. Heavy metal contents of Azidirachta indica collected from Akungba ...

    African Journals Online (AJOL)

    Azadirachta indica has many medicinal values, particularly among the Africans, and these have been reported [9, 10, 11, 12, 13]. Plants located along highways .... of heavy metals indicate that significant heavy metal pollution from extraneous source(s) has taken place. Table 6 showed correlation coefficients carried out.


    Directory of Open Access Journals (Sweden)

    Marek Slávik,Tomáš Tóth


    Full Text Available In the middle area of Spiš, it is significantly burden by heavy metals what is documented by radical content of Hg in soil from Rudňany 58.583645 -1. On the content of heavy metals in vegetables grown in this soil it has the same effect. 61.5% samples exceeded the limit value of heavy metals. The most dangerous vegetables were Lactuca sativa L. The limit value was exceed in all determine heavy metals - Hg, Cd, Pb and Cu in this vegetables. In the case of Hg, the limit value exceed 93.86 times. For relatively safety is growing of Pisum sativum L., where there was no exceed any limits values. The root vegetables are dangerous, where the sample of Raphanus sativus L. exceed 6.71978 times the limit values for Pb although the content of lead in the soil was under hygienic limits. Transfer of heavy metals into consume parts of vegetables was no limited by high content of humus into soil. Transfer of heavy metals into consume parts of vegetables was no limited by weakly alkaline soil reaction. These factors are considered for factors limited mobility and input heavy metals into plants. We determined heavy metals by AAS method on a Varian 240 FS and method AMA 254.

  20. Physicochemical characteristics and heavy metal levels in soil ...

    African Journals Online (AJOL)

    Distribution pattern of heavy metals in petrol stations, abattoirs, mechanic workshops and hospital incinerator sites were Mn > Zn > Pb > Cd, while for dumpsites Zn > Mn > Pb > Cd. Pollution index indicated that soil qualities varied between slightly contaminated to severely polluted status. This showed that the heavy metal ...

  1. Evaluation of heavy metal uptake and translocation by Acacia ...

    African Journals Online (AJOL)

    Many organic and inorganic pollutants, including heavy metals are being transported and mixed with the cultivated soils and water. Heavy metals are the most dangerous pollutants as they are nondegradable and accumulate and become toxic to plants and animals. An experiment was conducted in the glasshouse to ...

  2. Characterization of Heavy Metals in Vegetables Using Inductive ...

    African Journals Online (AJOL)

    The heavy metals or trace elements play an important role in the metabolic pathways during the growth and development of plants, when available in required concentration. The heavy metal concentration of. Cadmium (Cd), Cobalt (Co), Copper (Cu), Iron (Fe), Nickel (Ni), Lead (Pb) and Zinc (Zn) was analyzed using ...

  3. Investigation of the origin and distribution of heavy metals around ...

    African Journals Online (AJOL)


    Apr 28, 2010 ... This study was based on the outcome of the soil geochemical survey which was conducted by the Council for Geoscience around Ebenezer Dam during .... Rock sampling: The concentrations of heavy metals in the soil were used to plot the .... Rose et al., 1979; Alloway et al., 1997). Heavy metals. Granitic.

  4. Ecological risk assessment of heavy metals pollution on irrigated ...

    African Journals Online (AJOL)

    This paper assessed the heavy metals pollution in irrigated soil of salanta river valley of Sharada industrial area with aim of assessing the potential ecological risk of Cd, Cu, Cr and Zn. Soil samples were collected from five plots randomly selected along the stream and heavy metals (Cd, Cu, Cr and Zn) and pH were ...

  5. Urban water pollution by heavy metals and health implication in ...

    African Journals Online (AJOL)

    Studies of common heavy metals were conducted at Onitsha, Anambra State, the most urbanized city in Southeastern Nigeria. It was discovered that both surface and subsurface water were heavily polluted. Seven (7) heavy metals namely: arsenic (As+2), cadmium (Cd+2), lead (Pb+2), mercury (Hg+2), zinc (Zn+2), copper ...

  6. Species sensitivity analysis of heavy metals to freshwater organisms. (United States)

    Xin, Zheng; Wenchao, Zang; Zhenguang, Yan; Yiguo, Hong; Zhengtao, Liu; Xianliang, Yi; Xiaonan, Wang; Tingting, Liu; Liming, Zhou


    Acute toxicity data of six heavy metals [Cu, Hg, Cd, Cr(VI), Pb, Zn] to aquatic organisms were collected and screened. Species sensitivity distributions (SSD) curves of vertebrate and invertebrate were constructed by log-logistic model separately. The comprehensive comparisons of the sensitivities of different trophic species to six typical heavy metals were performed. The results indicated invertebrate taxa to each heavy metal exhibited higher sensitivity than vertebrates. However, with respect to the same taxa species, Cu had the most adverse effect on vertebrate, followed by Hg, Cd, Zn and Cr. When datasets from all species were included, Cu and Hg were still more toxic than the others. In particular, the toxicities of Pb to vertebrate and fish were complicated as the SSD curves of Pb intersected with those of other heavy metals, while the SSD curves of Pb constructed by total species no longer crossed with others. The hazardous concentrations for 5 % of the species (HC5) affected were derived to determine the concentration protecting 95 % of species. The HC5 values of the six heavy metals were in the descending order: Zn > Pb > Cr > Cd > Hg > Cu, indicating toxicities in opposite order. Moreover, potential affected fractions were calculated to assess the ecological risks of different heavy metals at certain concentrations of the selected heavy metals. Evaluations of sensitivities of the species at various trophic levels and toxicity analysis of heavy metals are necessary prior to derivation of water quality criteria and the further environmental protection.

  7. Assessment of toxic heavy metal loading in topsoil samples within ...

    African Journals Online (AJOL)


    There is dearth in information on the impact of lime- stone and other mineral explorations on the surrounding environment in terms of heavy metals pollution in Nigeria. ... grinded using agate mortar. They were sieved using nylon sieve with 0.5 mm mesh size. Analyses of heavy metals and other soil properties. The pH of soil ...

  8. Removal of heavy metals from waste water of tanning leather ...

    African Journals Online (AJOL)

    unguis. The isolated fungi were investigated for their potential to remove heavy metals from wastewater effluent of tanning leather industry. Such effluent was alkaline (pH, 8.2) with high content of total soluble salts (30.6 mS/cm) and heavy metals ...

  9. Fungicide, antibiotic, heavy metal resistance and salt tolerance of ...

    African Journals Online (AJOL)

    Fungicide, antibiotic, heavy metal resistance and salt tolerance of root nodule isolates from Vicia palaestina. ... African Journal of Biotechnology ... The objective of this study was to investigate the effects of fungicides, antibiotics, heavy metal and salt on growth of Rhizobium isolates which isolated from the Vicia palaestina ...

  10. Heavy metal bioaccumulation in the fish communities of Areba River ...

    African Journals Online (AJOL)

    All the 22 fish species analysed were contaminated with heavy metals ranging from 2 to 7 times above the WHO and New Zealand maximum acceptable limits for food. Fe and Zn were the highest bioaccumulated heavy metals while Mn and V where generally the lowest. Ni was not detected in Ischthys henryi, so also were ...

  11. Heavy metal biosorption sites in Penicillium cyclopium | Tsekova ...

    African Journals Online (AJOL)

    The biomass of Penicillium cyclopium was subjected to chemical treatment to study the role of the functional groups in the biosorption of heavy metal ions. The modifications of the functional groups were examined with infrared spectroscopy. Hydroxyl groups were identified as providing the major sites of heavy metal ...

  12. Relationships between heavy metals in the catfish, Chrysicthys ...

    African Journals Online (AJOL)

    Relationships between heavy metals in the catfish, Chrysicthys nigrodigitatus , water column and sediments of taylor creek, southern Nigeria. ... The best relationships were observed for Ni-Zn (r=0.72) and Cd-Pb (r=0.65). Partitioning coefficients (£d) of heavy metals between dissolved phase and SPM were generally low, ...

  13. urban dietary heavy metal intake from protein foods and vegetables

    African Journals Online (AJOL)


    ABSTRACT. Contamination of food and food products by heavy metals has made dietary intake as one of the major routes of these harmful elements to human beings. The human dietary intake of heavy metals cadmium, copper, lead and zinc from protein-foods (beans, meat, fish, milk) and green vegetables consumed daily ...

  14. Urban Dietary Heavy Metal Intake from Protein Foods and ...

    African Journals Online (AJOL)

    Contamination of food and food products by heavy metals has made dietary intake as one of the major routes of these harmful elements to human beings. The human dietary intake of heavy metals cadmium, copper, lead and zinc from protein-foods (beans, meat, fish, milk) and green vegetables consumed daily from ...

  15. assessment of heavy metals concentrations in the surface water of ...

    African Journals Online (AJOL)


    This work aimed at assessing the concentrations of heavy metals in the surface water of Bompai-. Jakara drainage basin. The points of ... Keywords: Heavy metals, surface water, drainage basin, standard limit. INTRODUCTION. Water pollution in .... discrepancies in values obtained. Pb concentrations recorded in this study ...

  16. Sorption of Heavy Metal Ions from Mine Wastewater by Activated ...

    African Journals Online (AJOL)



    Dec 2, 2016 ... Buah, W. K. and Dankwah, J. R. (2016), “Sorption of Heavy Metals from Mine Wastewater by Activated. Carbons Prepared ... A study on sorption of heavy metal ions: Lead (Pb2+), Copper (Cu2+) and Cadmium (Cd2+) from mine wastewater by activated ... (Pb), having relatively high densities and are toxic.

  17. A bioseparation process for removing heavy metals from waste ...

    African Journals Online (AJOL)

    A bioseparation process for removing heavy metals from waste water using biosorbents. ... The presence of heavy metals in the environment is of major concern because of their toxicity, bioaccumulating tendency, and threat to human life and the environment. In recent years, many low cost sorbents such as algae, fungi ...

  18. Heavy Metals Levels in Fish Samples from North Central Nigerian ...

    African Journals Online (AJOL)

    Heavy Metals Levels in Fish Samples from North Central Nigerian Rivers. IS Eneji, E Ogah, R Vesuwe, LA Nnamonu, R Sha'Ato. Abstract. Most aquatic organisms are capable of accumulating heavy metals to concentrations much higher than those present in water and sediments in their environment. In this piece of work, ...

  19. Heavy Metals in Soils and Tomatoes Grown in Urban Fringe ...

    African Journals Online (AJOL)


    Heavy metals are ubiquitous in the environment, as a result of both natural and anthropogenic activities, and humans are exposed to them through various pathways. (Wilson and Pyatt, 2007). Heavy metals like iron, tin, copper, manganese and vanadium occur naturally in the environment and could serve as plant nutrients.

  20. Concentrations of Heavy Metals in Some Important Rivers of Owerri ...

    African Journals Online (AJOL)

    Water samples from Rivers Azaraegbelu, Ogochie, Okatankwu and Otamiri were analyzed for lead (Pb), arsenic (As), cadmium (Cd) and zinc (Zn). The concentration of lead was highest in water samples ... values of the heavy metals analyzed. Keywords: Heavy metals, concentration, river, pollution, bioavailability, toxicity ...

  1. Heavy Metal Concentrations In A West African Sahel Reservoir ...

    African Journals Online (AJOL)

    ... mean concentrations varied significantly between stations (P<0.05). The concentrations of heavy metals were below contamination levels and fall within the limits reported for other West African small sahel reservoirs. Keywords: Heavy metals, Pollutants, Environment, Alau reservoir, Sahel, Enrichment Animal Research ...

  2. Concentration of heavy metals in a Niger Delta Mangrove Creek ...

    African Journals Online (AJOL)

    ... was no statistically significant difference (P > 0.05) in the concentration of heavy metals at the study stations. The EDTA hardness depicts hard water condition. The extremely low levels of the toxic heavy metals, Ni, Cr, Pb, Cd, and Hg, and total hydrocarbon content (THC) of <1 mg/l indicate that the water was not polluted.

  3. Heavy metal bioaccumulation and biomarkers of oxidative stress in ...

    African Journals Online (AJOL)

    Human activities can have dramatic effects on animal populations around urban areas with heavy metal contamination being a primary cause of harm. Amphibians, as residents of aquatic systems and with their semi-permeable skin are especially susceptible to heavy metal contamination. To better understand the effect of ...

  4. Assessment of heavy metal contamination in raw milk for human ...

    African Journals Online (AJOL)

    The presence of heavy metals in various farm inputs, including feed, fertilizer, water and environment leads to excretion of the residues in animals' milk. Because consumption of milk contaminated with heavy metals poses serious threats to consumers' health, a study was conducted in 2012 – 2013 in Pakistan to evaluate ...

  5. Heavy metals in soils of cocoa plantation (Theobroma cacao L.) (United States)

    Cocoa has experienced significant growth in recent years in Peru and the presence of heavy metals in the soils of these plantations is a potential problem for the export of this product. Contents of heavy metals (Cd, Ni, Pb, Fe, Cu, Zn, Mn) in soils from 19 plantations that have been in production f...

  6. Assessment of heavy metal pollution in soils along major roadside ...

    African Journals Online (AJOL)


    living organisms, when permissible concentration levels are exceeded. Heavy ... index (Igeo), and (3) Classify heavy metals by their similarities and ..... and classify metals. Statistical analysis. Analysis of variance was employed to determine whether groups of variables have the same mean. Sites showed no significant ...

  7. Influence of different concentration of heavy metals on the seed ...

    African Journals Online (AJOL)


    Some heavy metals in higher doses may cause metabolic disorders and growth inhibition for most of the plant species. This study was performed in order to evaluate two tomato varieties (Barakat and. Local tomato) response to ordinary Heavy Metals (Fe, Pb and Cu) in northern of Iran. Five doses (0,. 0.001, 0.01, 0.1 and ...

  8. Comparative assessment of heavy metal removal by immobilized ...

    African Journals Online (AJOL)

    Microorganisms play a vital role in heavy metal contaminated soil and wastewater by the mechanisms of biosorption. In this study, heavy metal resistant bacteria were isolated from an electroplating industrial effluent samples that uses copper, cadmium and lead for plating. These isolates were characterized to evaluate their ...

  9. Comparative Studies on Mosses for Heavy Metals Pollution ...

    African Journals Online (AJOL)

    Ekiti, a rural town was investigated using mosses grown in the localities as possible bio-indicators. The sources of these heavy metals were discovered to include: vehicular emission and incineration of domestic wastes and the heavy metals from ...

  10. Determination of heavy metals and genotoxicity of water from an ...

    African Journals Online (AJOL)

    Thus, the present study aimed to quantify and evaluate the heavy metal genotoxicity of artesian water in the city by Atomic absorption spectrophotometer analysis and testing with the Allium cepa test, respectively. This study reveals a chemical contamination in well water in the city, caused by the presence of heavy metals.

  11. Heavy Metal Music and Adolescent Suicidality: An Empirical Investigation. (United States)

    Scheel, Karen R.; Westefeld, John S.


    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…

  12. heavy metals pollution on surface water sources in kaduna ...

    African Journals Online (AJOL)

    ABSTRACT. This study examine the effects of heavy metal pollutants to aquatic ecosystems and the environment by considering the role of urban, municipal, agricultural, industrial and other anthropogenic processes as sources of heavy metal pollution in surface water sources of Kaduna metropolis. Samples of the polluted ...

  13. Assessment of heavy metals concentrations in coastal sediments in ...

    African Journals Online (AJOL)


    This study was undertaken to evaluate the heavy metals contamination of copper, zinc, manganese, iron, chromium ... Key words: Marine pollution, heavy metals, coastal sediments, toxicity, Nosy Be, Mahajanga, Madagascar. INTRODUCTION .... source of Cd and Pb in sediments come from ferry port activities and from the ...

  14. Heavy metal contamination of selected spices obtained from Nigeria ...

    African Journals Online (AJOL)


    KEYWORDS: heavy metal; contamination; Nigeria; spices; health; daily intake. Over the millennia, spices have been used in changing world's cuisine and medicine (Dukes,. 2003). Regrettably, significant quantities of heavy metals have been detected in natural food spices such as pepper and mustard (Krejpcio, 2007; ...

  15. X-ray fluorescence spectroscopic determination of heavy metals and ...

    African Journals Online (AJOL)

    Purpose: To determine the heavy metal and trace element composition of the powdered aerial parts of. Origanum sipyleum L. and its water extract. Methods: The heavy metal and trace elements content of the powdered plant material and 2 % aqueous extract were evaluated by x-ray fluorescence spectroscopy with silicon ...

  16. Assessment of heavy metal pollution in soils along major roadside ...

    African Journals Online (AJOL)

    ... to create awareness of vehicular heavy metal pollution to Botswana policy makers in the mitigation of vehicular pollution, as it is barely monitored. Key words: Heavy metal contamination, roadside soils, enrichment factors, contamination factor, pollution load index, geoaccumulation index, cluster analysis, factor analysis.

  17. Heavy Metals Accumulation Characteristics of Vegetables in Hangzhou City, China

    Directory of Open Access Journals (Sweden)

    GU Yan-qing


    Full Text Available A field survey of heavy metal concentrations in soils and vegetables grown in 30 vegetable farmlands of Hangzhou City were carried out. Through calculating the bioconcentration factor(BCFand transfer factor(TFfor different heavy metals(Cu, Zn, Cd, Cr and Pbin 27 kinds of different vegetables which belong to leafy vegetables, root vegetables or eggplant fruit vegetables, assessing their accumulation characteristics of heavy metals according to the differences of the bio-concentration factor, the reasonable proposals were put forward to optimize the planting structure of vegetables in mild and middle-level heavy metal contamination soils. The experimental results were as follows: In soils with mild and middle-level heavy metal contamination, leafy vegetables, such as crown daisy, cabbage, celery and Chinese long cabbage, had relatively low enrichment ability of heavy metals, so as the root and fruit vegetables like white radish, carrot, tomatoes, hence these vegetables could be planted preferentially. In contrast, some kinds of vegetables, including white amaranth, red amaranth, tatsoi, broccoli, gynura, brassica juncea and lettuce of leafy vegetables, lactuca sativa, taro, red radish and cherry radish of rhizome vegetables and sweet pepper of fruit vegetables, had relatively high accumulation ability of heavy metal, which should be avoided to be planted in soils with mild and middle-level heavy metal contamination.

  18. Heavy metal contamination of soil and sediment in Zambia | Ikenaka ...

    African Journals Online (AJOL)

    Heavy metal pollution is one of the most important problems in Zambia and causes serious effects to humans and animals. The aim of the present study was to evaluate the spatial distribution of heavy metals in main areas of Zambia and understand the characteristics of the pollution in each area. River and lake sediments ...

  19. Heavy metals accumulation in edible part of vegetables irrigated ...

    African Journals Online (AJOL)

    Hassana Ibrahim Mustapha

    In this present study, the quality of municipal wastewater used for irrigation of spinach was investigated for its heavy metal build-up. The municipal wastewater used for irrigation and the irrigated spinach samples were collected and analyzed for their heavy metal concentrations. The results indicate that the municipal ...

  20. Heavy metal accumulation in Melilotus officinalis under crown Olea ...

    African Journals Online (AJOL)



    Nov 5, 2008 ... wastewater has been applied for 7 years. This would provide knowledge that guides future research into the protection of the environment and domestic animals from exposure to heavy metals with potential to cause health problems. Although total concentrations of heavy metals in soil poorly indicate their ...

  1. Classification of Plants According to Their Heavy Metal Content ...

    African Journals Online (AJOL)

    The classes of plant species according to their accumulated heavy metals around North Mara Gold Mine were not known. ... requirements, optimizations, growth rates and the incidence of pests and diseases are required on the identified heavy metal hyperaccumulator plants for possible future remediation of the study area.

  2. Uptake and elimination kinetics of heavy metals by earthworm ...

    African Journals Online (AJOL)

    Earthworm inoculation of petroleum hydrocarbon contaminated soil is thought to catalyze the bioremediation. Most bioremediation studies focus on the petroleum hydrocarbon content and not on the heavy metals. Here, the uptake kinetics of heavy metals by earthworm in used engine oil contaminated soil was investigated.

  3. Utilization of Plant Refuses as Component of Heavy Metal Ion ...

    African Journals Online (AJOL)

    Waste materials like fruit and vegetable refuses were utilized as component of sensors capable of detecting heavy metals like lead ions and mercury ions by electrochemical method. The ability of the fabricated sensors to detect the presence of heavy metals was analyzed using electrochemical methods like cyclic ...

  4. assessment of heavy metal concentration in water around the ...

    African Journals Online (AJOL)


    lead, nickel and zinc (EU 1998, TBS 2005,. WHO 2008).When heavy metal concentrations in water exceed ... that the dependency of heavy metal concentration on rainfall variations can be complex (Meybeck ..... IAEA 2009 Nuclear energy series establishment of uranium mining and processing operations in the context of ...

  5. Determination of Heavy Metal Genotoxicity and their Accumulation ...

    African Journals Online (AJOL)


    ABSTRACT: This study investigated bioaccumulation of heavy metals and cytogenotoxic effects that could result from exposure of fish to heavy metals in the Asa River, Ilorin, Nigeria. The three different fish species, Tilapia zilli, Oreochromis niloticus and Sarotherodon galilaeus were obtained from the Asa River and the ...

  6. Determination of heavy metals in chinese prickly ash from different ...

    African Journals Online (AJOL)

    The highest concentrations of Pb and As in CPA exceeded the maximum permissible limits in China. Based on current safety standards, the concentrations of heavy metals in these CPA samples mean they are safe for human consumption. Conclusions: The status of heavy metal concentrations of CPA should be further ...

  7. Study on physicochemical and heavy metals (Pb, Fe, Mn ...

    African Journals Online (AJOL)

    A study on the physicochemical and heavy metals concentration of drinking water in Dutse Jigawa State was conducted between May, 2010 and February 2011. The parameters analyzed were the colour, odour, taste, temperature, turbidity, conductivity, pH, alkalinity, total hardness, dissolved oxygen and some heavy metals ...

  8. Levels of some heavy metals in cassava and plantain from ...

    African Journals Online (AJOL)


    ABSTRACT: The concentrations of heavy metals (Ni, Zn, Cu, Pb and Fe) were determined in cassava and plantain from farmlands in kaani and Kpean Communities in Khana Local. Government Area of Rivers State, Nigeria. Samples were collected, prepared, digested and analyzed using AAS. The levels of heavy metals ...

  9. Heavy metal accumulation in Melilotus officinalis under crown Olea ...

    African Journals Online (AJOL)



    Nov 5, 2008 ... This study was conducted to investigate heavy metal accumulation in Melilotus officinalis under crown. Olea europaea L forest in Rey town (Tehran, Iran), irrigated with wastewater and well water. Zn, Pb, Cr and Ni were determined at two sites. Heavy metal total concentrations (mg kg-1) in clay soils of pH ...

  10. Heavy metals accumulation in vegetables grown along the ...

    African Journals Online (AJOL)

    Heavy metals accumulation in vegetables grown along the Msimbazi River in Dar es Salaam, Tanzania. ... International Journal of Biological and Chemical Sciences ... With exception to Ipomea batata, other vegetables contained at least two types of heavy metals with high concentrations beyond the permissible values ...

  11. Synergistic Effects of Heavy Metals and Pesticides in Living Systems

    Directory of Open Access Journals (Sweden)

    Nitika Singh


    Full Text Available There is a widespread repeated exposure of the population to the pesticides and heavy metals of occupational and environmental origin. Such population is forced to undergo continuous stress imposed by combined exposure of the heavy metals and different classes of the pesticides used in agricultural as well as health practices. The existing reports from several workers have indicated that heavy metals and pesticides in combination may lead more severe impact on the human health when compared to their individual effects. Such a combination of pesticides and heavy metals may also change or influence the detection of exposure. Several studies in past have shown the synergistic toxic effects of heavy metals and pesticides. Such evaluations have revealed the synergistic interactions of various heavy metals and pesticides in animals as well as humans. The aim of the present article is to provide a synthesis of existing knowledge on the synergistic effects of heavy metal and pesticides in living systems. The information included in this article may be useful for different environment protection agencies and policy makers to consider the combined effects of heavy metals and pesticides on humans while designing strategies toward environmental protection and safety regulations about human health.

  12. Removal of heavy metals from aqueous solution by using mango ...

    African Journals Online (AJOL)



    Mar 14, 2011 ... waste pollution, thermal pollution, shipping water pollution and radioactive wastes (Tyagi and Mehra, 1994). Heavy metals such as zinc, lead and chromium ... alkalis, acids, detergents and heat, which may enhance the amount of the metal sorbed. When non-viable biomass is used in the removal of heavy ...

  13. Distribution of Heavy Metals in the Coastal Marine Surficial ...

    African Journals Online (AJOL)

    the trend of pollution in coastal areas has been increasing over time. In Tanzania, heavy metals in sediments have been determined in the Dar es. Salaam harbour (Machiwa 1992, 2000) and along. River Msimbazi (A'khabuhaya and Lodenius. 1988). Heavy metals concentration have also been measured from sediments ...

  14. Assessment of Heavy Metal Status of Boreholes in Calabar South ...

    African Journals Online (AJOL)

    Assessment of Heavy Metal Status of Boreholes in Calabar South Local Government Area, Cross River State, Nigeria. GN Njar, AI Iwara, RA Offiong, TD Deekor. Abstract. Although, many heavy metals are necessary in small amounts for the normal development of the biological cycles, most of them become toxic at high ...

  15. Stabilization of heavy metals in MSWI fly ash using silica fume

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinying; Chen, Quanyuan [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China); State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620 (China); Zhou, Yasu [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China); Tyrer, Mark [Mineral Industry Research Organisation, Solihull B37 7HB (United Kingdom); Yu, Yang [School of Environment Science and Engineering, Donghua University, Shanghai 201620 (China)


    Highlights: • The stabilization of heavy metals in MSWI fly ash was investigated. • The addition of silica fume effectively reduced the leaching of Pb and Cd. • The relation of solid phase transformation and leaching behavior of heavy metals was discussed. - Abstract: The objective of this work was to investigate the feasibility and effectiveness of silica fume on stabilizing heavy metals in municipal solid waste incineration (MSWI) fly ash. In addition to compressive strength measurements, hydrated pastes were characterized by X-ray diffraction (XRD), thermal-analyses (DTA/TG), and MAS NMR ({sup 27}Al and {sup 29}Si) techniques. It was found that silica fume additions could effectively reduce the leaching of toxic heavy metals. At the addition of 20% silica fume, leaching concentrations for Cu, Pb and Zn of the hydrated paste cured for 7 days decreased from 0.32 mg/L to 0.05 mg/L, 40.99 mg/L to 4.40 mg/L, and 6.96 mg/L to 0.21 mg/L compared with the MSWI fly ash. After curing for 135 days, Cd and Pb in the leachates were not detected, while Cu and Zn concentrations decreased to 0.02 mg/L and 0.03 mg/L. The speciation of Pb and Cd by the modified version of the European Community Bureau of Reference (BCR) extractions showed that these metals converted into more stable state in hydrated pastes of MSWI fly ash in the presence of silica fume. Although exchangeable and weak-acid soluble fractions of Cu and Zn increased with hydration time, silica fume addition of 10% can satisfy the requirement of detoxification for heavy metals investigated in terms of the identification standard of hazardous waste of China.

  16. Approaches to metal speciation analysis in natural waters (United States)

    Morrison, G. M. P.

    Approaches to the separation and identification of metal species in natural waters are discussed. Dissolved and colloidal metal species may be fractionated, on the basis of physico-chemical characteristics, by ion exchange, u.v. irradiation, resin adsorption, solvent extraction or strong acid digestion. Size fractionation techniques include filtration, centrifugation, dialysis, ultrafiltration and gel filtration chromatography. Suitable detection techniques, either before or after fractionation, are anodic stripping voltammetry, ion selective electrodes and atomic absorption. The bioavailable uptake rate of metal species may be determined by Dialysis with Receiving Resins.

  17. Reducing hazardous heavy metal ions using mangium bark waste. (United States)

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


    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.

  18. Lability of nanoparticulate metal complexes in electrochemical speciation analysis

    DEFF Research Database (Denmark)

    van Leeuwen, Herman P.; Town, Raewyn M.


    Lability concepts are elaborated for metal complexes with soft (3D) and hard (2D) aqueous nanoparticles. In the presence of a non-equilibrium sensor, e.g. a voltammetric electrode, the notion of lability for nanoparticulate metal complexes, M-NP, reflects the ability of the M-NP to maintain...... of the electrochemical technique is crucial in the lability towards the electrode surface. In contrast, for nanoparticulate complexes it is the dynamics of the exchange of the electroactive metal ion with the surrounding medium that governs the effective lability towards the electrode surface....... equilibrium with the reduced concentration of the electroactive free M2+ in its diffusion layer. Since the metal ion binding sites are confined to the NP body, the conventional reaction layer in the form of a layer adjacent to the electrode surface is immaterial. Instead an intraparticulate reaction zone may...

  19. Bioremediation of industrial effluents containing heavy metals using brewing cells of Saccharomyces cerevisiae as a green technology: a review. (United States)

    Soares, Eduardo V; Soares, Helena M V M


    The release of heavy metals into the environment, mainly as a consequence of anthropogenic activities, constitutes a worldwide environmental pollution problem. Unlike organic pollutants, heavy metals are not degraded and remain indefinitely in the ecosystem, which poses a different kind of challenge for remediation. It seems that the "best treatment technologies" available may not be completely effective for metal removal or can be expensive; therefore, new methodologies have been proposed for the detoxification of metal-bearing wastewaters. The present work reviews and discusses the advantages of using brewing yeast cells of Saccharomyces cerevisiae in the detoxification of effluents containing heavy metals. The current knowledge of the mechanisms of metal removal by yeast biomass is presented. The use of live or dead biomass and the influence of biomass inactivation on the metal accumulation characteristics are outlined. The role of chemical speciation for predicting and optimising the efficiency of metal removal is highlighted. The problem of biomass separation, after treatment of the effluents, and the use of flocculent characteristics, as an alternative process of cell-liquid separation, are also discussed. The use of yeast cells in the treatment of real effluents to bridge the gap between fundamental and applied studies is presented and updated. The convenient management of the contaminated biomass and the advantages of the selective recovery of heavy metals in the development of a closed cycle without residues (green technology) are critically reviewed.

  20. Effects of a reservoir flushing on trace metal partitioning, speciation and benthic invertebrates in the floodplain. (United States)

    Peter, Dorothea Hug; Castella, Emmanuel; Slaveykova, Vera I


    Elimination of sediments from river reservoirs is a common management problem for hydroelectric power plants. Periodical flushing can have negative impacts downstream. This study investigated the impact of a flushing event on the physico-chemical changes in the downstream sections and on the consequences for the benthic macroinvertebrate community. A special emphasis was placed on trace metal fate, partitioning and speciation. The assessment of taxonomic diversity and the frequency of taxa with specific traits was used to estimate the impact on the macroinvertebrate community. Trace metals were measured in the dissolved and particulate fraction, in the surface sediment and in selected macroinvertebrates. Bioanalogical diffusive gradient thin films (DGT) complemented the approach. The results showed an increase of Al, Co, Mn and Ni in the dissolved fraction (Mdis). Crdis, Fedis, Pbdis, and Cudis showed strong spatial variation. In the exchangeable fraction of particulate metals, trends were contrasted, depending on the metal. The calculated free ion and DGT concentrations increased during the flush for all metals, except for Cu. Accumulation in invertebrates increased only in a small number of cases. Macroinvertebrate diversity was negatively impacted as shown by lower taxonomic richness and rarefied richness after the event. Trait profiles were also affected. Overall, the study revealed that flushing operations have an impact on trace metal partitioning between dissolved, suspended particulate matter and sediments, metal speciation, as well as the functional invertebrate diversity.

  1. The influence of weathering and organic matter on heavy metals lability in silicatic, Alpine soils. (United States)

    Egli, Markus; Sartori, Giacomo; Mirabella, Aldo; Giaccai, Daniele; Favilli, Filippo; Scherrer, Daniel; Krebs, Rolf; Delbos, Evelyne


    We investigated the effect of organic matter and weathering on the lability and solid phase speciation of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) in two contrasting subalpine regions in the Italian Alps. Cr, Ni and Cu could be linked to weathering. This was not the case for Pb. Since organic matter (OM) influences the solid phase speciation of heavy metals, the total organic C and N content, the C and N content of different density fractions of OM and also of the labile (oxidised by H(2)O(2)) and stable (H(2)O(2)-resistant) fractions were determined. Soil OM stocks were high and soils on north-facing slopes had more OM than the south-facing sites to which they were paired. Density measurements and the H(2)O(2) fractionation indicated that the higher OM content on north-facing sites was due to an accumulation of weakly degraded organic material. Due to higher weathering intensity on north-facing sites, the abundance of the EDTA-extractable heavy metals was higher than on south-facing sites. All EDTA-extractable heavy metals showed a good correlation to the water-soluble phenolic concentrations which indicates that the metals were probably translocated as metal-organic complexes. Pb and Cu correlate not only to the light (density labile, organic fraction but also to the heavy (density > 2 g/cm(3)) and stable fraction. High-mountain ecosystems like the Alps are sensitive to changing environmental conditions such as global warming. A warmer climate and the more favourable conditions it brings for biological activity, especially at cooler sites, will probably lead in the short- to mid-term to an increased loss of accumulated, weakly degraded OM. As the Pb and Cu content is significantly related to the labile organic matter pools, the risk exists that an increase in OM mineralisation could affect the storage capacity and mobility of these metals in soils. Copyright 2009 Elsevier B.V. All rights reserved.

  2. Heavy metals in the environment; uncertainty and sensitivity analysis of spatial predictions of heavy metals in wheat

    NARCIS (Netherlands)

    Brus, D.J.; Jansen, M.J.W.


    Heavy metals seriously threaten the health of human beings when they enter the food chain. Therefore, policymakers require precise predictions of heavy metal concentrations in agricultural crops. In this paper we quantify the uncertainty of regression predictions of Cd and Pb in wheat (Triticum

  3. Modeling of Heavy Metal Transformation in Soil Ecosystem (United States)

    Kalinichenko, Kira; Nikovskaya, Galina N.


    The intensification of industrial activity leads to an increase in heavy metals pollution of soils. In our opinion, sludge from biological treatment of municipal waste water, stabilized under aerobic-anaerobic conditions (commonly known as biosolid), may be considered as concentrate of natural soil. In their chemical, physical and chemical and biological properties these systems are similar gel-like nanocomposites. These contain microorganisms, humic substances, clay, clusters of nanoparticles of heavy metal compounds, and so on involved into heteropolysaccharides matrix. It is known that microorganisms play an important role in the transformation of different nature substances in soil and its health maintenance. The regularities of transformation of heavy metal compounds in soil ecosystem were studied at the model of biosolid. At biosolid swelling its structure changing (gel-sol transition, weakening of coagulation contacts between metal containing nanoparticles, microbial cells and metabolites, loosening and even destroying of the nanocomposite structure) can occur [1, 2]. The promotion of the sludge heterotrophic microbial activities leads to solubilization of heavy metal compounds in the system. The microbiological process can be realized in alcaligeneous or acidogeneous regimes in dependence on the type of carbon source and followed by the synthesis of metabolites with the properties of flocculants and heavy metals extragents [3]. In this case the heavy metals solubilization (bioleaching) in the form of nanoparticles of hydroxycarbonate complexes or water soluble complexes with oxycarbonic acids is observed. Under the action of biosolid microorganisms the heavy metals-oxycarbonic acids complexes can be transformed (catabolised) into nano-sizing heavy metals- hydroxycarbonates complexes. These ecologically friendly complexes and microbial heteropolysaccharides are able to interact with soil colloids, stay in the top soil profile, and improve soil structure due

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

    Directory of Open Access Journals (Sweden)

    Bechan Sharma


    Full Text Available 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.

  5. Biomedical implications of heavy metals induced imbalances in redox systems. (United States)

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


    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.

  6. Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems (United States)

    Singh, Shweta; Siddiqi, Nikhat J.


    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

  7. Heavy metal contamination of stream water and sediment in the Taejon area

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyoung Woong [Paichai University, Taejon (Korea, Republic of); Lee, Hyun Koo [Chungnam National University, Taejon (Korea, Republic of)


    Associated with the rapid pace of overpopulation and industrialization is the increase of municipal and industrial wastewater and heavy metal contamination from these point sources have received much attention in the Taejon area. To reduce the environmental problems, 21 stream sediments from Gap-chun, Yudeung-chun, Yusung-chun and Keum river have been analyzed for Cd, Cu, Pb and Zn. The results show that heavy metal concentrations are high in sediments from the Sintanjin and Taehwa Industrial Complex area with particular reference to 1388 {mu}g/g Cu in the stream sediment of Yusung-chun. When the geochemical map drawn from the Kriging technique of these data are compared with the industrialization and urbanization index map, high concentrations of heavy metals are found in stream sediments in industrialized areas resulting from the accumulation of heavy metals from the polluting factories. Concentrations of Cu in sediments from the Taehwa Industrial Complex area and those of Zn in sediments from the Sintanjin Complex area higher than EPA standard in the U.S.A and may be the potential sources of pollution in Keum river with possible implications to human health. For the speciation of Cu, Pb and Zn, the high proportions of exchangeable phase of Cu and Zn in stream sediments indicate that the metals originate not from parent materials but from wastewater and exist as the adsorbed phase on the surface of sediments. These metals are easily dissolved into the water by the reaction and relative amounts of easily dissolved phase of metals are in the order of Cu = Zn > Pb. (author). 17 refs., 4 tabs., 7 figs.

  8. Cell surface engineering of microorganisms towards adsorption of heavy metals. (United States)

    Li, Peng-Song; Tao, Hu-Chun


    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.

  9. Human health risk assessment of heavy metals in urban stormwater. (United States)

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


    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 (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. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Multiple heavy metal removal using an entomopathogenic fungi Beauveria bassiana. (United States)

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


    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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Heavy metal sensitivity and bioconcentration in oribatid mites (Acari, Oribatida)

    Energy Technology Data Exchange (ETDEWEB)

    Skubala, Piotr, E-mail: [Department of Ecology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland); Zaleski, Tomasz [Department of Soil Science and Soil Protection, Agricultural University in Krakow, Mickiewicza 21, 31-120 Cracow (Poland)


    In this study we aimed to identify different reactions of oribatid species to heavy metal pollution and to measure concentrations of cadmium, zinc and copper in oribatid species sampled along a gradient. Oribatid mites were sampled seasonally during two years in five meadows located at different distances from the zinc smelter in the Olkusz District, southern Poland. Oribatids were shown to withstand critical metal concentration and established comparatively abundant and diverse communities. The highest abundance and species richness of oribatids were recorded in soils with moderate concentrations of heavy metals. Four different responses of oribatid species to heavy metal pollution were recognized. Heavy metals (Zn, Pb, Cd, Ni) and various physical (bulk density, field capacity, total porosity) and chemical (K{sub av}, P{sub av}, N, C, pH) factors were recognized as the structuring forces that influence the distribution of oribatid species. Analysis by atomic absorption spectrophotometry revealed large differences in metal body burdens among species. None of the species can be categorized as accumulators or non-accumulators of the heavy metals - the pattern depends on the metal. The process of bioconcentration of the toxic metal (regulated) and essential elements (accumulated) was generally different in the five oribatid species studied. - Highlights: Black-Right-Pointing-Pointer Responses of oribatid mites to metal contamination along a gradient in meadow soils were studied. Black-Right-Pointing-Pointer Small concentrations of heavy metals positively influenced the abundance of oribatid mites. Black-Right-Pointing-Pointer Four different responses of oribatid species to heavy metal pollution were recognised. Black-Right-Pointing-Pointer Bioaccumulation of the toxic metal and essential elements proceeded differently in oribatid species. Black-Right-Pointing-Pointer Five studied oribatid species were deconcentrators of cadmium.

  12. Heavy metals in vegetables and potential risk for human health

    Directory of Open Access Journals (Sweden)

    Fernando Guerra


    Full Text Available Ingestion of vegetables containing heavy metals is one of the main ways in which these elements enter the human body. Once entered, heavy metals are deposited in bone and fat tissues, overlapping noble minerals. Slowly released into the body, heavy metals can cause an array of diseases. This study aimed to investigate the concentrations of cadmium, nickel, lead, cobalt and chromium in the most frequently consumed foodstuff in the São Paulo State, Brazil and to compare the heavy metal contents with the permissible limits established by the Brazilian legislation. A value of intake of heavy metals in human diets was also calculated to estimate the risk to human health. Vegetable samples were collected at the São Paulo General Warehousing and Centers Company, and the heavy metal content was determined by atomic absorption spectrophotometry. All sampled vegetables presented average concentrations of Cd and Ni lower than the permissible limits established by the Brazilian legislation. Pb and Cr exceeded the limits in 44 % of the analyzed samples. The Brazilian legislation does not establish a permissible limit for Co contents. Regarding the consumption habit of the population in the São Paulo State, the daily ingestion of heavy metals was below the oral dose of reference, therefore, consumption of these vegetables can be considered safe and without risk to human health.

  13. Microalgae - A promising tool for heavy metal remediation. (United States)

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


    Biotechnology of microalgae has gained popularity due to the growing need for novel environmental technologies and the development of innovative mass-production. Inexpensive growth requirements (solar light and CO2), and, the advantage of being utilized simultaneously for multiple technologies (e.g. carbon mitigation, biofuel production, and bioremediation) make microalgae suitable candidates for several ecofriendly technologies. Microalgae have developed an extensive spectrum of mechanisms (extracellular and intracellular) to cope with heavy metal toxicity. Their wide-spread occurrence along with their ability to grow and concentrate heavy metals, ascertains their suitability in practical applications of waste-water bioremediation. Heavy metal uptake by microalgae is affirmed to be superior to the prevalent physicochemical processes employed in the removal of toxic heavy metals. In order to evaluate their potential and to fill in the loopholes, it is essential to carry out a critical assessment of the existing microalgal technologies, and realize the need for development of commercially viable technologies involving strategic multidisciplinary approaches. This review summarizes several areas of heavy metal remediation from a microalgal perspective and provides an overview of various practical avenues of this technology. It particularly details heavy metals and microalgae which have been extensively studied, and provides a schematic representation of the mechanisms of heavy metal remediation in microalgae. Copyright © 2014 Elsevier Inc. All rights reserved.


    Directory of Open Access Journals (Sweden)



    Full Text Available Results of examinations on the amount, and spatial distribution of heavy metal compounds in the soil of Debrecen, their geographic, pedologic and ecologic aspects are presented in this study. The effects of the differences in traffic conditions, build-up/land use and the density of vegetation on the heavy metal content of the soils have been examined in city of Debrecen and its closer environment.Cadmium-, cobalt-, nickel-, lead-, and copper-contents of the soil samples taken from 88 sites of the sample area have been studied after acidic extraction, using atomic absorption spectrometer with the flame technique. Close-to-background concentrations of heavy metals in unpolluted soils of the forested area of the Nagyerd were determined. Spatial differences in the heavy metal content of the soils for the whole area of Debrecen have been studied. Influence of soil properties (humus, Calcium- Carbonate content, pH and grain-size distribution on the binding and mobility of heavy metals in the soil has been examined. Vertical distribution and mobility of heavy metal compounds in acid sandy soils was determined. Heavy metal content of soil in the most sensitive areas, playgrounds, recreational areas, urban gardens and grazing fields along busy roads has been surveyed.

  15. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild


    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test...... organism. Stormwater and pond water from a catchment with light industry showed high levels of heavy metals, especially zinc and copper. The pond water showed high toxic effects and copper were found to be the main toxicant. Additionally, a large part of the copper was suspected to be complex bound......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...

  16. Assessment of factors related to heavy metals distribution in abandoned mining soils in Madrid, central Spain (United States)

    Torres, Manuel; Carral, Pilar; Alvarez, Ana M.; Hernández, Zulimar; Lorena, Recio-Vázquez; Marques, Maria J.; Almendros, Gonzalo


    Exploitation of metallic mineral deposits and its subsequent abandonment in last decades has lead to significant environmental hazard for natural systems. The present study concerns the distribution and mobility of heavy metals and trace elements mainly As, Cu, Cd, Co, Mn and V, in sulphide-rich soils. The site studied (Sierra de Guadarrama, Garganta de los Montes, Madrid) is at 1200 m asl. Soils are Humic and Dystric Cambisols (WRB) developed on gneisses; the main minerals consist of sulphides and include chalcopyrite, pyrite, marcasite, galena and arsenopyrite. Concentration data of the different species of heavy metals as dependent variables in addition to a series of independent variables mainly soil organic matter were subjected to multivariate chemometric treatments including multidimensional scaling (MDS), principal component analysis (PCA) and support vector machine (SVM) for a preliminary survey on the possible role of soil organic matter in the distribution and speciation of heavy metals in soils. The soil heavy metals speciation was determined using the BCR (Community Bureau of Reference, European Commission) sequential extraction procedure and analysed by ICP-MS. The total contents of these elements were calculated as the sum of the four BCR fractions. The results showed element concentrations decreasing with the distance from the source of pollution. The highest amounts of As and Mn, and Cu, Cd, Co and V were found at 10 and 100 m respectively. These values exceed the allowed limits of the environmental regulation. The percentages of extractable elements (step one of BCR) in relation to total elements show that Cu and Cd were significantly more easily extractable than the other elements. Metal availability in soils was generally controlled by total metal concentration. Data processing techniques coincided in pointing out the association of high levels of organic matter with the concentrations of elements extracted just in the most available forms: i

  17. Heavy Metal Contents in Some Commonly Consumed Vegetables

    African Journals Online (AJOL)


    effects on consumers of the vegetables. The regulations on food quality have lowered the maximum permissible levels of toxic metals in human food and this call for a good and vigorous food quality control on the concentrations of trace metals in food. The mean and range of heavy metals concentrations in eight green ...

  18. Heavy metal content of selected African leafy vegetables planted in ...

    African Journals Online (AJOL)


    Data analysis. Data on metal content obtained from the AAS was analyzed for variance using ANOVA and multiple mean comparisons were done using Tukeys at 5% level. Pearson's Product Moment was used to correlate the amount of metal in soil to that in the plant. RESULTS AND DISCUSSION. Heavy metals in soils.

  19. Steam Gasification of Sawdust Biochar Influenced by Chemical Speciation of Alkali and Alkaline Earth Metallic Species

    Directory of Open Access Journals (Sweden)

    Dongdong Feng


    Full Text Available The effect of chemical speciation (H2O/NH4Ac/HCl-soluble and insoluble of alkali and alkaline earth metallic species on the steam gasification of sawdust biochar was investigated in a lab-scale, fixed-bed reactor, with the method of chemical fractionation analysis. The changes in biochar structures and the evolution of biochar reactivity are discussed, with a focus on the contributions of the chemical speciation of alkali and alkaline earth metallic species (AAEMs on the steam gasification of biochar. The results indicate that H2O/NH4Ac/HCl-soluble AAEMs have a significant effect on biochar gasification rates. The release of K occurs mainly in the form of inorganic salts and hydrated ions, while that of Ca occurs mainly as organic ones. The sp3-rich or sp2-sp3 structures and different chemical-speciation AAEMs function together as the preferred active sites during steam gasification. H2O/HCl-soluble AAEMs could promote the transformation of biochar surface functional groups, from ether/alkene C-O-C to carboxylate COO− in biochar, while they may both be improved by NH4Ac-soluble AAEMs. H2O-soluble AAEMs play a crucial catalytic role in biochar reactivity. The effect of NH4Ac-soluble AAEMs is mainly concentrated in the high-conversion stage (biochar conversion >30%, while that of HCl-soluble AAEMs is reflected in the whole activity-testing stage.

  20. Heavy metal music and adolescent suicidality: an empirical investigation. (United States)

    Scheel, K R; Westefeld, J S


    This study investigated the relationship between preference for heavy metal music and vulnerability to suicide among 121 high school students. Heavy metal fans had less strong reasons for living (especially male fans) and had more thoughts of suicide (especially female fans). For a large majority, listening to music (all types) had a positive effect on mood. Overall, the results indicate that preference for heavy metal music among adolescents may be a "red flag" for increased suicidal vulnerability, but also suggest that the source of the problem may lie more in personal and familial characteristics than in any direct effects of the music. Implications for intervention and for future research are discussed.

  1. Variegate porphyria and heavy metal poisoning from ingestion of "moonshine". (United States)

    Hughes, G S; Davis, L


    A patient with cavitary tuberculosis, hepatic cirrhosis, bullous skin lesions over sun-exposed surfaces, disorientation, and a chronic, as well as recent, history of illicit alcohol consumption was found to have acute variegate porphyria by characteristic fecal and urinary porphyrin studies. Elevated levels of lead and arsenic were found in serum and urine without evidence of heavy metal storage in hair and liver. We suspect that the variegate porphyria was precipitated by the ingestion of heavy metals contained in illicit alcohol. In a patient with disorientation, bullous skin lesions, and a history of illicit alcohol ingestion, one must consider heavy metal intoxication and secondary porphyrin abnormalities.

  2. Speciation and leaching of trace metal contaminants from e-waste contaminated soils. (United States)

    Cui, Jin-Li; Luo, Chun-Ling; Tang, Chloe Wing-Yee; Chan, Ting-Shan; Li, Xiang-Dong


    Primitive electrical and electronic waste (e-waste) recycling activities have caused serious environmental problems. However, little is known about the speciation and leaching behaviors of metal contaminants at e-waste contaminated sites. This study investigated trace metal speciation/mobilization from e-waste polluted soil through column leaching experiments involving irrigation with rainwater for almost 2.5 years. Over the experimental period, Cu and Zn levels in the porewater were 0.14±0.08mg/L, and 0.16±0.08mg/L, respectively, increasing to 0.33±0.16mg/L, and 0.69±0.28mg/L with plant growth. The amounts of Cu, Zn, and Pb released in surface soil (0-2cm) contributed 43.8%, 22.5%, and 13.8%, respectively, to the original levels. The released Cu and Zn were primarily caused by the mobilization of the carbonate species of metals, including Cu(OH) 2 , CuCO 3 , and Zn 5 (CO 3 ) 2 (OH) 6 , and amorphous Fe/Mn oxides associated fractions characterized by sequential extraction coupling with X-ray absorption spectroscopy. During the experiments, trace metals were not detected in the effluent, and the re-sequestration of trace metals was mainly attributed to the adsorption on the abundant Fe/Mn oxides in the sub-layer soil. This study quantitatively elucidated the molecular speciation of Cu and Zn in e-waste contaminated soil during the column leaching process. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Leaching behavior and immobilization of heavy metals in solidified/stabilized products. (United States)

    Malviya, Rachana; Chaudhary, Rubina


    Solidification/stabilization (S/S) of hazardous sludge from steel processing plant has been studied. Mechanical strength and leaching behavior test of solidified/stabilized product was performed. Mechanical strength decreases with increase in waste content. Pb, Zn, Cu, Fe and Mn could be considerably immobilized by the solidification/stabilization process. The elements least immobilized were Na, K, and Cl. Leaching of heavy metals in the S/S matrix can be considered as pH dependent and corresponding metal hydroxide solubility controlled process. Geochemical modeling was performed for the prediction of speciation. On the basis of test results, mobility and mechanism of leaching was assessed. Dominant leaching mechanism was surface wash off in the initial stages followed by diffusion for Pb, Zn, Cu, Fe and Mn. Diffusion coefficient was above 11.5 indicating low mobility in the cement matrix.

  4. Coupling bioleaching and electrokinetics to remediate heavy metal contaminated soils. (United States)

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


    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 (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.

  5. Selection of ectomycorrhizal willow genotype in phytoextraction of heavy metals. (United States)

    Hrynkiewicz, Katarzyna; Baum, Christel


    Willow clones are used for the phytoextraction of heavy metals from contaminated soils and are usually mycorrhizal. The receptiveness of willow clones for mycorrhizal inoculum varies specific to genotype; however, it is unknown if this might have a significant impact on their efficiency in phytoextraction of heavy metals. Therefore, a model system with mycorrhizal and non-mycorrhizal willows of two different genotypes--one with usually stronger natural mycorrhizal colonization (Salix dasyclados), and one with lower natural mycorrhizal colonization (S. viminalis)--was investigated for its efficiency of phytoextraction of heavy metals (Cd, Pb, Cu, Zn) from contaminated soil. Inoculation with the ectomycorrhizal fungus Amanita muscaria significantly decreased the biomass of leaves of both inoculated willow clones, and increased or had no effect on the biomass of trunks and roots of S. dasyclados and S. viminalis, respectively. The concentrations of heavy metals in the biomass of S. dasyclados were in general higher than in S. viminalis irrespective of inoculation with the ectomycorrhizal fungus. Inoculation with A. muscaria significantly decreased the concentration of Cu in the trunks of both Salix taxa, but did not affected the concentrations of other heavy metals in the biomass. In conclusion, stronger receptiveness of willow clones for mycorrhizal inoculum was correlated with an increased total extraction of heavy metals from contaminated soils. Therefore, this seems to be a suitable criterion for effective willow clone selection for phytoremediation. Increased biomass production with relatively constant metal concentrations seems to be a major advantage of mycorrhizal formation of willows in phytoremediation of contaminated soils.

  6. Heavy metal contamination of groundwater resources in a Nigerian ...

    African Journals Online (AJOL)

    conductivity meter (Jenway model), while the concentrations of the heavy metals (Co, Fe, Pb and Cu) were determined using atomic absorption spectrophotometer (AAS). The trend of dispersion of each variable was demonstrated on Landsat ETM+ ...

  7. Seasonal variation in heavy metal concentration in mangrove foliage

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A; Wafar, S.; Bhosle, N

    Seasonal variation in the concentration of some heavy metals in the leaves of seven species of mangrove vegetation from Goa, revealed that maximum concentration of iron and manganese occurs during the monsoon season without any significant toxic...

  8. Adsorption of heavy metals by agroforestry waste derived activated ...

    African Journals Online (AJOL)

    Adsorption of heavy metals by agroforestry waste derived activated carbons applied to aqueous solutions. Jane M Misihairabgwi, Abisha Kasiyamhuru, Peter Anderson, Colin J Cunningham, Tanya A Peshkur, Ignatious Ncube ...

  9. Heavy metal pollution of vegetable crops irrigated with wastewater ...

    African Journals Online (AJOL)

    144) and edible parts of both exotic and traditional vegetables (samples = 240) irrigated with wastewater from some parts of Accra were studied. The concentrations of heavy metals in mg/l were quantified in wastewater from Accra and ...

  10. De novo transcriptome assembly of heavy metal tolerant Silene dioica

    Czech Academy of Sciences Publication Activity Database

    Čegan, R.; Hudzieczek, V.; Hobza, Roman


    Roč. 11, MAR (2017), s. 118-119 ISSN 2213-5960 Institutional support: RVO:61389030 Keywords : genome * Silene dioica * RNA-Seq * Transcriptome * Heavy metal tolerance * Sex chromosomes Subject RIV: EB - Genetics ; Molecular Biology

  11. Baby Teeth Link Autism and Heavy Metals, NIH Study Suggests (United States)

    ... Release Thursday, June 1, 2017 Baby teeth link autism and heavy metals, NIH study suggests Cross-section ... Sinai Health System Baby teeth from children with autism contain more toxic lead and less of the ...

  12. Polysiloxane based CHEMFETs for the detection of heavy metal ions

    NARCIS (Netherlands)

    Lugtenberg, R.J.W.; Antonisse, M.M.G.; Egberink, Richard J.M.; Engbersen, Johannes F.J.; Reinhoudt, David


    The development of polysiloxane based chemically modified field effect transistors (CHEMFETs) for heavy metal ions is described. Different polar siloxane copolymers have been synthesized via an anionic copolymerization of hexamethylcyclotrisiloxane,

  13. Estimation of Heavy Metals in Neem Tree Leaves along Katsina ...

    African Journals Online (AJOL)

    Michael Horsfall

    Garcia and Millan, 1998). The Nigerian situation is further exacerbated by the reality of increasing large-scale importation of old/fairly used vehicles for use on the Nigerian highways (Alo, 2008). Heavy metals are important group of pollutants.

  14. Antimicrobial, heavy metal resistance and plasmid profile of ...

    African Journals Online (AJOL)

    The antimicrobial, heavy metal resistance patterns and plasmid profiles of Coliforms (Enterobacteriacea) isolated from nosocomial infections and healthy human faeces were compared. Fifteen of the 25 isolates from nosocomial infections were identified as Escherichia coli, and remaining as Kelebsiella pneumoniae.

  15. 255 effects of some heavy metal pollutants on fertility characteristics

    African Journals Online (AJOL)



    ) and Zinc (Zn). As Aydinalp and Marinova (2003) observe, a precise knowledge of heavy metals concentration and the forms in which they are found, their dependence on soil's physico-chemical properties provide a basis.

  16. Phycoremediation of Wastewater: Heavy Metal and Nutrient Removal Processes

    Directory of Open Access Journals (Sweden)

    Kwarciak-Kozłowska Anna


    Full Text Available Phycoremediation is the use of algae for the removal or biotrans-formation of pollutants from wastewater. The study is a novel at-tempt to integrate nutrient (N and P removal and some heavy met-als (iron, manganese and zinc bioaccumulation from municipal wastewater using two microalgae species: Chlorella vulgaris and Scenedesmus armatus. The Chlorella vulgaris showed higher re-moval of total nitrogen (TN both in influent and effluent waste water than Scenedesmus armatus. Nevertheless, more than 51% of total phosphorus (TP in effluent and 36% in influent wastewaters were removed by Scenedesmus armatus. More efficient microalga in heavy metal removal in influent wastewater was Scenedesmus armatus. The results showed that Chlorella vulgaris was appropriate for TN removal and bioaccumulation of heavy metals from effluent wastewater. Nevertheless, Scenedesmus armatus was highly pref-erable for heavy metals removal from influent wastewater.

  17. Removal of nutrient and heavy metal loads from sewage effluent ...

    African Journals Online (AJOL)


    Jul 4, 2015 ... tial of vetiver grass in removing nutrient and heavy metal loads from wastewater ... retention using the methods of water analysis described by. Sauter and ..... forming an immobilised microbial biomass on supporting surfaces ...

  18. Study of Correlation Between Heavy Metal Concentration, Street ...

    African Journals Online (AJOL)

    ABSTRACT: This study was aimed at evaluating heavy metal contents in street dust of five major roads within the trunk of Kano metropolis. The dust were collected from heavy traffic roads of the city which include Zaria road (ZR), Maiduguri road (MR), Katsina road (KR), Hadejia road (HR) and Bayero University Kano road ...

  19. Effect of irrigation on heavy metals content of wastewater irrigated ...

    African Journals Online (AJOL)

    There is an urgent need to educate farmers on the dangers of the presence of heavy metals in soils as well as the quality of irrigation water especially if it comes from tanning industries for increased crop production. Accordingly, soil and irrigation wastewater study was conducted to assess the concentrations of heavy ...

  20. Studies of heavy metal contents and microbial composition of ...

    African Journals Online (AJOL)


    Waste engine oil in soil creates unsatisfactory conditions for plant growth ranging from heavy metal toxicity to ... perennial which grows best in warm frost-free areas. Guinea grass can withstood continuous heavy grazing .... These identified as active members ofbioremediation microbial consortia by Ekundayo and Obuekwe.

  1. Heavy metal contamination of amaranthus grown along major ...

    African Journals Online (AJOL)

    Consumption of food contaminated with heavy metals is a major source of health problems for man and animals. Vegetable cropping along major highways with heavy vehicular movement has been a serious concern to food safety experts in large cities. A study was, therefore, carried out in two major highways in Lagos, ...

  2. Assessment of heavy metal pollution in soils along major roadside ...

    African Journals Online (AJOL)


    1Department of Agricultural Engineering and Land Planning, Botswana College of Agriculture, Private Bag 0027,. Gaborone, Botswana. 2Department of Basic Sciences, Botswana College of ... residents along roads with heavy traffic loads are subjected to increasing levels of contamination with heavy metals (Ghrefat and ...

  3. Study of Correlation Between Heavy Metal Concentration, Street ...

    African Journals Online (AJOL)

    This study was aimed at evaluating heavy metal contents in street dust of five major roads within the trunk of Kano metropolis. The dust were collected from heavy traffic roads of the city which include Zaria road (ZR), Maiduguri road (MR), Katsina road (KR), Hadejia road (HR) and Bayero University Kano road (BR).

  4. Atmospheric heavy metal deposition in the Copenhagen area

    DEFF Research Database (Denmark)

    Andersen, Allan; Hovmand, Mads Frederik; Johnsen, Ib


    Atmospheric dry and wet deposition (bulk precipitation) of the heavy metals Cu, Pb, Zn, Ni, V and Fe over the Copenhagen area was measured by sampling in plastic funnels from 17 stations during a twelve-month period. Epigeic bryophytes from 100 stations in the area were analysed for the heavy met...


    African Journals Online (AJOL)


    metals in O. sativa grains harvested locally as well as to set the baseline levels of some heavy ... Machiwa – Heavy Metal Levels in Paddy Soils and Rice … .... where 0.5 g of dried soil or rice (polished rice and paddy rice) samples were weighed in 50 ml volumetric flasks. De-ionized water. (1 ml) was added, the flasks were ...

  6. Heavy metal adsorption by montmorillonites modified with natural organic cations


    Cruz-Guzmán Alcalá, M.; Celis, R.; Hermosín, M.C.; Koskinen, W. C.; Nater, E. A.; Cornejo, J.


    Agricultural and industrial pollution release large amounts of heavy metals into the atmosphere, surface water, soil, and plants. The protection and restoration of soils and water contaminated with heavy metals generate a great need to develop efficient adsorbents for these pollutants. This study reports the adsorption of Pb(II) and Hg(II) by two reference montmorillonites, Wyoming (SWy-2) and Arizona (SAz-1), that were pretreated with various natural organic cations containing different func...

  7. Antibiogram and heavy metal tolerance of bullfrog bacteria in Malaysia


    M. Najiah; Tee, L.W.


    Bacterial isolates from 30 farmed bullfrogs (Lithobates catesbeianus) weighing 500-600 g at Johore, Malaysia with external clinical signs of ulcer, red leg and torticollis were tested for their antibiograms and heavy metal tolerance patterns. A total of 17 bacterial species with 77 strains were successfully isolated and assigned to 21 antibiotics and 4 types of heavy metal (Hg2+, Cr6+, Cd2+, Cu2+). Results revealed that bacteria were resistant against lincomycin (92%), oleandomycin (72.7%) an...

  8. Spatiotemporal Analysis of Heavy Metal Water Pollution in Transitional China


    Huixuan Li; Yingru Li; Ming-Kuo Lee; Zhongwei Liu; Changhong Miao


    China’s socioeconomic transitions have dramatically accelerated its economic growth in last three decades, but also companioned with continuous environmental degradation. This study will advance the knowledge of heavy metal water pollution in China from a spatial–temporal perspective. Specifically, this study addressed the following: (1) spatial patterns of heavy metal water pollution levels were analyzed using data of prefecture-level cities from 2004 to 2011; and (2) spatial statistical met...

  9. Phytochelatin biosynthesis and function in heavy-metal detoxification. (United States)

    Cobbett, C S


    Plants respond to heavy-metal toxicity via a number of mechanisms. One such mechanism involves the chelation of heavy metals by a family of peptide ligands, the phytochelatins. Molecular genetic approaches have resulted in important advances in our understanding of phytochelatin biosynthesis. In particular, genes encoding the enzyme phytochelatin synthase have been isolated from plant and yeast species. Unexpectedly, genes with similar sequences to those encoding phytochelatin synthase have been identified in some animal species.

  10. Heavy Metals in Soils of auto- mechanic shops and refuse ...

    African Journals Online (AJOL)

    Atomic Absorption Spectrophotometer (UnicamSolaar32 model) was used for analyzing the digested soil samples for heavy metal content. Mean concentrations of the selected heavy metals in the dumpsite soil at Apir were 0.003 mg/Kg, 0.2414 mg/Kg, 0.2552 mg/Kg, 0.1882 mg/Kg and 0.0210 mg/Kg for Cd, Cr, Cu, Pb and ...

  11. Distribution of heavy metals from flue gas in algal bioreactor (United States)

    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.

  12. Research on heavy metal pollution of river Ganga: A review

    Directory of Open Access Journals (Sweden)

    Dipak Paul


    Full Text Available River Ganga is considered sacred by people of India for providing life sustenance to environment and ecology. Anthropogenic activities have generated important transformations in aquatic environments during the last few decades. Advancement of human civilization has put serious questions to the safe use of river water for drinking and other purposes. The river water pollution due to heavy metals is one of the major concerns in most of the metropolitan cities of developing countries. These toxic heavy metals entering the environment may lead to bioaccumulation and biomagnifications. These heavy metals are not readily degradable in nature and accumulate in the animal as well as human bodies to a very high toxic amount leading to undesirable effects beyond a certain limit. Heavy metals in riverine environment represent an abiding threat to human health. Exposure to heavy metals has been linked to developmental retardation, kidney damage, various cancers, and even death in instances of very high exposure. The following review article presents the findings of the work carried out by the various researchers in the past on the heavy metal pollution of river Ganga.

  13. Content of some heavy metals in soil and corn grain

    Energy Technology Data Exchange (ETDEWEB)

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


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

  14. Comparison of Eleven Heavy Metals in Moringa Oleifera Lam. Products. (United States)

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


    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.


    Directory of Open Access Journals (Sweden)

    D. Bulgariu


    Full Text Available In this paper are presented the results of mineralogical and geochemical studies, realized for few soils from Giurgeu Mountains, which have as main purpose the distribution and mobility interpretation of minor elements (Cd, Cu, Pb, Zn, Bi in studied soil samples. The determination of fixed fractions and mobile fractions weight, at total contents of studied elements, and relative association of these elements with main mineral and organic components of soil samples, was realized on the basis of results obtained by sequential solid/ liquid extraction. The same, we try to use the correlation establish between metallic ions contents, as indicators of mineral paragenesis (the genetic type and formation conditions. The obtained results are agree with the results of similar studies from literature and they, underline of some interesting aspects about of distribution and migration of heavy metals in soils: (1 exist of some selectivity in heavy metals distribution in mineral components from soils, correlated with reciprocals geochemical affinities between speciation forms of metals and mineral components, in a given pedogeochemical context; (2 the heavy metals distribution between solid phases and soil solution are realized in competitive regime, and the inter-phases equilibrium evolution are thermodynamic and kinetics controlled by the solid/ liquid interfaces processes; (3 the fast elementary processes and local fluctuations of physic-chemical parameters are the main factors which controlled the inter-phases transfer ratio and the evolution direction of equilibriums of heavy metals distribution.

  16. Factors Affecting the Binding of a Recombinant Heavy Metal-Binding Domain (CXXC motif Protein to Heavy Metals

    Directory of Open Access Journals (Sweden)

    Kamala Boonyodying


    Full Text Available A number of heavy metal-binding proteins have been used to study bioremediation. CXXC motif, a metal binding domain containing Cys-X-X-Cys motif, has been identified in various organisms. These proteins are capable of binding various types of heavy metals. In this study, heavy metal binding domain (CXXC motif recombinant protein encoded from mcsA gene of S. aureus were cloned and overexpressed in Escherichia coli. The factors involved in the metal-binding activity were determined in order to analyze the potential of recombinant protein for bioremediation. A recombinant protein can be bound to Cd2+, Co2+, Cu2+ and Zn2+. The thermal stability of a recombinant protein was tested, and the results showed that the metal binding activity to Cu2+ and Zn2+ still exist after treating the protein at 85ºC for 30 min. The temperature and pH that affected the metal binding activity was tested and the results showed that recombinant protein was still bound to Cu2+ at 65ºC, whereas a pH of 3-7 did not affect the metal binding E. coli harboring a pRset with a heavy metal-binding domain CXXC motif increased the resistance of heavy metals against CuCl2 and CdCl2. This study shows that metal binding domain (CXXC motif recombinant protein can be effectively bound to various types of heavy metals and may be used as a potential tool for studying bioremediation.

  17. Heavy metals in five Sabellidae species (Annelida, Polychaeta): ecological implications. (United States)

    Giangrande, Adriana; Licciano, Margherita; Del Pasqua, Michela; Fanizzi, Francesco Paolo; Migoni, Danilo; Stabili, Loredana


    The present work analyzed three hard-bottom and two soft-bottom species of sabellid polychaetes to determine the content of several heavy metals in their branchial crown and body. The highest concentrations of heavy metals were recorded in the hard-bottom species Branchiomma bairdi, a recent Mediterranean introduction. Differences in the metal concentrations were most notable in the high trace metal levels of the branchial crown for all the studied species. Statistical analysis showed that the Mediterranean hard-bottom species were similar each other in their heavy metal content in the body as well as in the branchial crown and appeared separated from all the other species. Arsenic and vanadium hyperaccumulation in the branchial crowns of the considered sabellid species probably acts as a deterrent for predation. The observed differences among the examined species were discussed not only at the light of habitat colonization but also in terms of the phylogeny.

  18. Electrokinetic treatment of an agricultural soil contaminated with heavy metals. (United States)

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


    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.

  19. Phytoremediation of heavy metals--concepts and applications. (United States)

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


    The mobilization of heavy metals by man through extraction from ores and processing for different applications has led to the release of these elements into the environment. Since heavy metals are nonbiodegradable, they accumulate in the environment and subsequently contaminate the food chain. This contamination poses a risk to environmental and human health. Some heavy metals are carcinogenic, mutagenic, teratogenic and endocrine disruptors while others cause neurological and behavioral changes especially in children. Thus remediation of heavy metal pollution deserves due attention. Different physical and chemical methods used for this purpose suffer from serious limitations like high cost, intensive labor, alteration of soil properties and disturbance of soil native microflora. In contrast, phytoremediation is a better solution to the problem. Phytoremediation is the use of plants and associated soil microbes to reduce the concentrations or toxic effects of contaminants in the environments. It is a relatively recent technology and is perceived as cost-effective, efficient, novel, eco-friendly, and solar-driven technology with good public acceptance. Phytoremediation is an area of active current research. New efficient metal hyperaccumulators are being explored for applications in phytoremediation and phytomining. Molecular tools are being used to better understand the mechanisms of metal uptake, translocation, sequestration and tolerance in plants. This review article comprehensively discusses the background, concepts and future trends in phytoremediation of heavy metals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Heavy metal music meets complexity and sustainability science. (United States)

    Angeler, David G


    This paper builds a bridge between heavy metal music, complexity theory and sustainability science to show the potential of the (auditory) arts to inform different aspects of complex systems of people and nature. The links are described along different dimensions. This first dimension focuses on the scientific aspect of heavy metal. It uses complex adaptive systems theory to show that the rapid diversification and evolution of heavy metal into multiple subgenres leads to a self-organizing and resilient socio-musicological system. The second dimension builds on the recent use of heavy metal as a critical thinking model and educational tool, emphasizing the artistic component of heavy metal and its potential to increase people's awareness of environmental sustainability challenges. The relationships between metal, complexity theory and sustainability are first discussed independently to specifically show mechanistic links and the reciprocal potential to inform one domain (science) by the other (metal) within these dimensions. The paper concludes by highlighting that these dimensions entrain each other within a broader social-cultural-environmental system that cannot be explained simply by the sum of independent, individual dimensions. Such a unified view embraces the inherent complexity with which systems of people and nature interact. These lines of exploration suggest that the arts and the sciences form a logical partnership. Such a partnership might help in endeavors to envision, understand and cope with the broad ramifications of sustainability challenges in times of rapid social, cultural, and environmental change.

  1. Heavy metal adsorption of Streptomyces chromofuscus K101

    Directory of Open Access Journals (Sweden)

    Said Mohamed Daboor


    Full Text Available Objective: To find the best actinomycete that has potential application value in the heavy metal remediation due to its special morphological and physiological metabolism. Methods: In some areas of River Nile, Egypt, a total of 67 actinomycete isolates (17 isolates from surface water and 50 from sediment were identified. In addition, the studied area was characterized by a large amount of submerged macrophyte species Ceratophyllum demersum, one free floating species Eichhornia crassipes and two emergent species Polygonum tomentosum and Saccharum spontaneum with the highest biomass production values. Many methods are used in this research like qualitative evaluation of heavy metals, minimum inhibitory concentration of heavy metal determination, metal binding assay, heavy metal assessment, etc. Results: Many actinomycetes isolates were isolated from River Nile, Egypt, the absorbent efficiency of one isolate Streptomyces chromofuscusK101 showed the most efficient metal binding activity. The adsorption process of Zn2+ , Pb2+ and Fe 2+ single or mixture metal ions was investigated, where the order of adsorption potential ( Zn2+ >Pb2+ >Fe 2+ was observed in single metal reaction. The adsorption in mixed metal reactions was the same order as in single-metal ion with a significant decrease in Fe 2+ and Pb2+ adsorption. Conclusions: In conclusion the metal adsorption reactions were very fast, pH dependent and culture age-independent, suggestive of a physicochemical reaction between cell wall components and heavy metal ions. The absorbent removal efficiency was determined as a function of ion concentration, pH and temperature.

  2. Hyphenated techniques as tools for speciation analysis of metal-based pharmaceuticals: developments and applications. (United States)

    Meermann, Björn; Sperling, Michael


    Method development and applications of hyphenated techniques as tools for speciation analysis of metal-based pharmaceuticals are summarized within this review. Advantages and limitations of the separation modes-high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), and gas chromatography (GC)-as well as the detection modes-inductively coupled plasma-mass spectrometry (ICP-MS) and electrospray ionization-mass spectrometry (ESI-MS)-are discussed. ICP-MS detection is found to be advantageous for the quantification of drugs containing metals and other heteroatoms. The species-independent sensitivity and multielement capabilities of ICP-MS allow it to be used for quantification even when species-specific standards are not available, as well as to determine the stoichiometry in metallodrug-biomolecule interactions. Molecular information that is totally destroyed when ICP is applied as ionization source and is therefore not obtainable via ICP-MS detection can be accessed by the complementary technique of ESI-MS. Speciation analysis combining both elemental and molecular information is therefore a powerful tool for the analysis of metal-based pharmaceuticals and their metabolites in body fluids and other relevant matrices.

  3. Assessment of heavy metal removal technologies for biowaste by physico-chemical fractionation

    NARCIS (Netherlands)

    Veeken, A.H.M.; Hamelers, H.V.M.


    In the Netherlands, the heavy metal content of biowaste-compost frequently exceeds the legal standards for heavy metals. In order to assess heavy metal removal technologies, a physico-chemical fractionation scheme was developed to gain insight into the distribution of heavy metals (Cd, Cu, Pb and

  4. Body burdens of heavy metals in Lake Michigan wetland turtles. (United States)

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


    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.

  5. A Review on Recent Applications of High-Performance Liquid Chromatography in Metal Determination and Speciation Analysis. (United States)

    Rekhi, Heena; Rani, Susheela; Sharma, Neha; Malik, Ashok Kumar


    High-performance liquid chromatography (HPLC) has several advantages over the conventional methods due to their operational simplicity. It is a vital tool to determine metal ions having same mass but different electronic configuration, to separate complex mixtures and to resolve ions that may be indistinguishable by mass spectrometry alone. Metal ions play vital role in many biological processes and involved in setting up of many diseases. Therefore, the development of simple methods for the detection and quantification of metals in real samples might serve as diagnostic tools for various diseases. This review article focuses on the recent main feature of this technique, i.e. speciation of metal ions and their applications to series of problem of metal ion chemistry in different environmental matrixes. Speciation of metals is of increasing interest and has a great importance because of bioavailability, environmental mobility, toxicity and potential risk of metals. With the capability of partitioning the complex species of different metal ions, HPLC is an efficient technique for this task. This review summarizes recent advances in the development of HPLC to the fundamental understanding of metal ion chemistry in the environment and discusses all the issues that still need a lot of consideration. It has been classified into different sections depending on the role of HPLC in separation used and metal speciation; furthermore, the underlying sample preconcentration techniques and detection systems involved for the determination of metal ions and their applications were discussed.

  6. Determination of trace heavy metals in some textile products ...

    African Journals Online (AJOL)

    The concentrations of trace heavy metals in textile samples collected from Tokat, Turkey, were determined by flame and/or graphite furnace atomic absorption spectrometry after microwave digestion. The relative standard deviations for the determinations were found to be lower than 10 %. The concentrations of trace metals ...

  7. Assessment of heavy metals concentration in water, soil sediment ...

    African Journals Online (AJOL)

    The term heavy metal refers to any metallic chemical element that has a relatively high density and is toxic at low concentrations. This study was conducted in four eastern Rift Valley lakes which included Lakes Oloidien, Crater, Elementaita and Nakuru, to determine the presence and levels of lead, arsenic, cadmium and ...

  8. Study of Correlation Between Heavy Metal Concentration, Street ...

    African Journals Online (AJOL)

    needs to evaluate heavy metal content of water and food, the metal content of street has to be evaluated ... were recorded. The samples (dust) were transferred to clean labeled polyethylene bags and were directly ..... cell membranes via anion transport system in to the cell, the compounds are readily reduced to trivalent.

  9. Potential Human Health Risk Assessment of Heavy Metals Intake via ...

    African Journals Online (AJOL)


    Key Words: Heavy Metals, leafy vegetable, daily intake of metals, health risk index, target hazard quotient. (THQ), zinc, lead .... Family. Parts used/ consumed. 1. Telferia occidentalis. Fluted pumpkin. Ugu. Cucurbitaceae ..... Characterization and functional properties. .... Science and Total Environment, 350: 28–37. Zhou, H ...

  10. Bioaccumulation of heavy metals in water, sediment and fish ...

    African Journals Online (AJOL)

    The highest levels of heavy metal accumulated in the liver of C. anguillaris were Fe, Cu, Pb, Cd and Zn than accumulated in O. niloticus. In gills of C. anguillaris, the highest accumulation of metal levels were Zn, Fe, Pb, Cd and Cu than accumulation in gills of O. niloticus. In muscles of C. anguillaris, the highest accumulation ...

  11. Biomonitoring of heavy metals pollution in Lake Burullus, Northern ...

    African Journals Online (AJOL)


    Aquatic macrophytes and benthos are unchangeable biological filters and they carry out purification of the water bodies by accumulating dissolved metals and toxins in their tissues. In view of their potential to entrap several toxic heavy metals, 3 groups of benthos and 6 macrophytes (submerged species: Potamogeton.

  12. Assessment of Heavy Metal Content of Branded Pakistani Herbal ...

    African Journals Online (AJOL)


    The plants imbibe toxic metals in various ways including the environment they grow in, contaminated water, agricultural expedients, storage environment and manufacturing processes [7]. The purpose of this study was to evaluate the heavy metals contents of some selected herbal products available in the Pakistani market.

  13. Tolerance and Accumulation of Heavy Metals by Descurainia sophia L.

    Directory of Open Access Journals (Sweden)

    Hoda Karamooz


    Full Text Available Today, biosphere pollution has accelerated strongly with start of industrial revolution by toxicity of heavy metals. One of existing pollution is soil pollution. Unfortunately, soil pollution by metals is as intensive environmental stress for plant hence for human. Plants, which are able to store heavy metals in their organs, can be used for phytoremediation of polluted soils and utilization of these plants is effective for phytoremediation as a cheap and economic method. In this research, the absorption rate of Cd (II, Ni (II by Descurainia sophia was considered in hydroponic conditions. Plants were grown in Hoagland media containing different concentrations of Cd (II, Ni (II. An experiment in a completely randomized design with three replications was conducted. Two weeks after treatment of plants the sample were gathered and metal concentration was measured by atomic absorption spectroscopy. Besides, the content of chlorophyll and proline was measured. The results showed the chlorophyll content in high concentrations of the metals (Cd (II, Ni (II was decreased in plants that were sign of pigment degradation in presence of heavy metals. Similarly, the proline content in plants was increased under stress which was sign of damage of heavy metal stress on plant and activation of defensive mechanisms in this condition. The effects of toxic concentration of nickel and cadmium on metal accumulation in these plants showed that roots were able to absorb more than shoots, which is sign of elements connection to root cell wall.

  14. Assessment of Heavy Metal Contamination in Soils around Cassava ...

    African Journals Online (AJOL)

    Wageningen, the Netherlands. Sheppard, D.S., Claridge, G.G.C. and Campbell,. I.B.(2000). Metal contribution of soil at Scott urban-rural land use gradients. Applied. Geochemistry, 15: 513-530. Umoren, I.U. and Onianwa, P.C. (2005). Concentrations and distribution of some heavy metals in urban soils of Ibadan, Nigeria.

  15. Modeling effluent heavy metal concentrations in a bioleaching ...

    African Journals Online (AJOL)


    Artifical neural networks practices were used to predict the recovery of heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) from dewatered metal plating sludge (with no sulfide or sulfate compounds) using bioleaching process involving Acidithiobacillus ferrooxidans. The bioleaching process was operated as a completely mixed batch ...


    African Journals Online (AJOL)


    People want to be able to buy clothing, bedding and household textiles that have been tested and are not dyed in any way with harmful substances [6-8]. Textile products contain some organic and inorganic substance including trace metal ions. Especially, reactive and pigment dyes contain trace heavy metals at high level.

  17. Toxic effect of heavy metals on aquatic environment | Baby ...

    African Journals Online (AJOL)

    The indiscriminate discharge of industrial effluents, raw sewage wastes and other waste pollute most of the environments and affect survival and physiological activities of target organisms. Metals in particular have a tendency to accumulate and undergo food chain magnification. Heavy metals affect all groups of organisms ...

  18. Nutrients and heavy metal distribution in thermally treated pig manure

    DEFF Research Database (Denmark)

    Kuligowski, Ksawery; Poulsen, Tjalfe G.; Stoholm, Peder


    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...

  19. Determination of Some Heavy Metals Levels in Funaria ...

    African Journals Online (AJOL)

    This was attributed to the concentrations of motor vehicles and some industries that have increased in the town over time. Other heavy metals (Cd and Ni) were found in relatively smaller concentrations. The absorption of these metals was related to their concentrations in the atmosphere as a result of industrial and ...

  20. Determination of essential and heavy metals in Kenyan honey by ...

    African Journals Online (AJOL)

    In this project, honey samples collected from different parts of Kenya, namely, Laikipia, Baringo, Nairobi, Ngong, Mbeere, Embu, Kitui, Kibwezi and Lamu were analysed to determine the levels of selected heavy metals (Pb, Cd, Zn, Cu, As) and essential metals (K, Na, Ca, Mg, Fe). The samples were analysed using flame ...

  1. Electrochemical activity of heavy metal oxides in the process of ...

    Indian Academy of Sciences (India)

    The influence of heavy metal oxides on the chloride induced corrosion of steel reinforcement in concrete was studied. Significant inhibition and stimulation of chloride induced corrosion have been observed. Basicity and acidity of the relevant metal ions, and their ability to form complexes are considered as the main factors ...

  2. Determination of some heavy metals in spinach and lettuce from ...

    African Journals Online (AJOL)

    Heavy metals such as copper, zinc, cadmium and lead were analyzed in vegetable samples (lettuce and spinach) obtained from ten major markets within Kaduna ... From the stipulated limits set by WHO/FAO, consumers of vegetables from this study areas were likely to be liable to copper toxicity and some few metals as ...

  3. Analysis of Some Heavy Metals in Grass ( Paspalum Orbiculare ...

    African Journals Online (AJOL)

    The increased deposition of trace metals from vehicle exhausts on plants has raised concerns about the risks of the quality of food consumed by humans since the heavy metals emitted through the exhaust by vehicles can enter food chain through deposition on grass grazed by animals. Grass (Paspalum Orbiculare) and ...

  4. Heavy metals burden in Kidney and heart tissues of Scarus ...

    African Journals Online (AJOL)

    Levels of selected heavy metals (Pb, Co, Cu, Ni, Zn, Mn and Cd) in the heart and kidney tissues of parrot fish, collected from the Arabian Gulf, Eastern Province of Saudi Arabia, were determined by wet-digestion based atomic absorption method. The results showed that accumulation pattern of analyzed metals in the kidney ...


    African Journals Online (AJOL)



    Feb 13, 2012 ... transported as either dissolved species in water or as an integral part ... In addition, to a small extent, the metals enter the human bodies via food, drinking water and air. Though, some heavy metals. (e.g. copper, selenium, zinc) are essential to maintain the .... The values of total suspended solids. (TSS) and ...

  6. Bioaccumulation of heavy metals in Amaranthus sp. L sold at ...

    African Journals Online (AJOL)

    The study was design to assess the bioaccumulation of heavy metals in spinach sold at vegetable farms at Katsina metropolis, using Atomic absorption spectrometer VPG 210 model for the metals analysis.The study reveals that cadmium has recorded highest concentration followed by chromium and zinc, at Kofar ...

  7. Concentration of heavy metals from traffic emissions on plant ...

    African Journals Online (AJOL)

    In recent years, emission and combustion of fossils and fuels have been identified as primary sources of atmospheric metallic burden. Detailed information about this is not readily available in Nigeria. This study was therefore carried out to determine the concentration of heavy metals (e.g. lead, mercury and cadmium} ...

  8. Levels of Petroleum Hydrocarbons and some Heavy Metals in ...

    African Journals Online (AJOL)

    Michael Horsfall

    water bodies receiving effluents is emphasized in order to forestall cumulative effects of pollutants which may lead to sub-lethal consequences in the aquatic ... heavy metal pollution (Osibanjo and Ajayi, 1980,. Foulkes. 1990). Bioaccumulation in ... Soluble metallic soaps were hydrolyzed by acidification. Oils and solids or ...

  9. Geospatial analyses in support of heavy metal contamination ...

    African Journals Online (AJOL)

    The results showed that NDVI values increased with distance from roads (R2 0.508-0.965; p < 0.05), indicating that proximity to roads reduced grass vigour. Metal concentrations in grass tissue were lower than in soil by an average factor of nine, but varied as the soil concentrations. The concentrations of the heavy metals ...

  10. Removal Of Heavy Metals From Industrial Wastewaters Using Local ...

    African Journals Online (AJOL)

    Wastewater samples from battery, paint and textile industries were treated with different doses of locally available alum, aluminum sulphate and ferric chloride in order to determine and compare their effectiveness in removing heavy metal contents from the wastewaters. The percentage removal of the metals from the ...

  11. Effect of Transport and Aging Processes on Metal Speciation in Iron Oxyhydroxide Aggregates, Tar Creek Superfund Site, Oklahoma (United States)

    Estes, E. R.; Schaider, L. A.; Shine, J. P.; Brabander, D. J.


    Following the cessation of mining activity in the late 20th century, Tar Creek Superfund Site was left highly contaminated by Pb, Zn, and Cd. Tar Creek, which flows through the site and into the Neosho River, has been studied extensively because of its potential to transport metals from the mining site to downstream communities. Previous research identified aggregated iron oxyhydroxide material, which forms when mine seepage mixes with Tar Creek surface water, as a major transport vector of metals. Frequent flooding in Tar Creek deposits aggregates on downstream floodplains, where wetting and drying processes alter the speciation of iron and other metals. This study seeks to better quantify those changes and to determine how transport and aging affects the human and ecological health risk. Sequential extractions of aggregate samples collected from the creek demonstrate that Fe is present in both amorphous (10-35% of Fe extracted) and more crystalline (8-23% of Fe extracted) phases. Substantial portions of heavy metals sorb to amorphous iron oxyhydroxide phases (accounting for 10-30% of Pb and Zn extracted) but are not associated with more crystalline iron oxide phases (representing only 1% or less of the Pb and Zn extracted). Samples have a high organic matter content (18-25% mass loss on ignition), but only Fe was significantly extracted by the oxidizing step targeting organic matter (1-2% of Pb and Zn extracted, but 10-26% of Fe extracted). The majority of metals were extracted by the soluble or residual steps. If metals and organic matter inhibit transformation of amorphous iron oxyhydroxide material to nano and crystalline iron oxides, then a steady-state volume of amorphous iron oxyhydroxide material with a high total sorption capacity may exist within Tar Creek, enhancing the metal flux accommodated by this transport mechanism. Once transported downstream and deposited on floodplains, however, it is hypothesized that repeated changes in soil matrix

  12. Assessment of heavy metal contents of green leafy vegetables

    Directory of Open Access Journals (Sweden)

    V. Jena


    Full Text Available Vegetables are rich sources of vitamins, minerals, and fibers, and have beneficial antioxidative effects. Ingestion of vegetables containing heavy metals is one of the main routes through which these elements enter the human body. Slowly released into the body, however, heavy metals can cause an array of diseases. In this study we investigated the concentrations of copper, chromium, zinc, and lead in the most frequently consumed vegetables including Pimpinella anisum, Spinacia oleracea, Amaranthus viridis, Coriandrum sativum, and Trigonella foenum graecum in various sites in Raipur city, India. Atomic absorption spectrophotometry was used to estimate the levels of these metals in vegetables. The mean concentration for each heavy metal in the samples was calculated and compared with the permissible levels set by the Food and Agriculture Organization and World Health Organization. The intake of heavy metals in the human diet was also calculated to estimate the risk to human health. Our findings indicated the presence of heavy metals in vegetables in the order of Cr > Zn > Cu > Pb. Based on these findings, we conclude that the vegetables grown in this region are a health hazard for human consumption.

  13. Heavy Metals Contamination of Table Salt Consumed in Iran (United States)

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


    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

  14. Mosses accumulate heavy metals from the substrata of coal ash

    Directory of Open Access Journals (Sweden)

    Vukojević Vanja


    Full Text Available Plants that are able to accumulate and tolerate extraordinarily high concentrations of heavy metals (hyperaccumulators can be used for phytoremediation (removal of contaminants from soils or phytomining (growing a crop of plants to harvest the metals. Two moss species, Bryum capillare Hedw. and Ceratodon purpureus Hedw., were tested as potential phytoremedies under in vivo conditions on a coal ash disposal site in the surroundings of Obrenovac (NW Serbia. The content of various heavy metals (iron, manganese zinc, lead, nickel, cadmium, and copper in the mosses and substrata were investigated over a period of three years. Iron and zinc were found to have the highest concentration in the mosses.

  15. Ecotoxicology of heavy metals: Liquid-phase extraction by nanosorbents (United States)

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


    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.

  16. Heavy metals contamination of Chrysichthys nigrodigitatus and ...

    African Journals Online (AJOL)

    In each case, four tissues; gills, bone, intestine and muscle were compared with the level of metals in the water. Lower concentrations of metals were recorded in water than in fish. Lower concentration of the metals found in fish and water was less than that recommended by the World Health Organisation (WHO) guideline ...

  17. Critical loads of heavy metals for soils

    NARCIS (Netherlands)

    Vries, de W.; Groenenberg, J.E.; Lofts, S.; Tipping, E.; Posch, M.


    To enable a precautionary risk assessment for future inputs of metals, steady-state methods have been developed to assess critical loads of metals avoiding long-term risks to food quality and eco-toxicological effects on organisms in soils and surface waters. A critical load for metals equals the

  18. Predatory insects as bioindicators of heavy metal pollution

    Energy Technology Data Exchange (ETDEWEB)

    Nummelin, Matti [Department of Biological and Environmental Sciences, P.O. Box 65, University of Helsinki, FIN-00014 (Finland)]. E-mail:; Lodenius, Martin [Department of Biological and Environmental Sciences, P.O. Box 65, University of Helsinki, FIN-00014 (Finland); Tulisalo, Esa [Department of Biological and Environmental Sciences, P.O. Box 65, University of Helsinki, FIN-00014 (Finland); Hirvonen, Heikki [Department of Biological and Environmental Sciences, P.O. Box 65, University of Helsinki, FIN-00014 (Finland); Alanko, Timo [Statistics Finland, FIN-00022 (Finland)


    Heavy metal concentrations of different predatory insects were studied near by a steel factory and from control sites. Waterstriders (Gerridae), dragon fly larvae (Odonata), antlion larvae (Myrmeleontidae) and ants (Formicidae) were analyzed by AAS. In most cases the metal concentrations were higher near the factory, but e.g. waterstriders had higher cadmium concentrations in control area. Discriminant analysis clearly reveals that all these insect groups can be used as heavy metal indicators. However, the commonly used ants were the least effective in indicating the differences between the factory and control sites. Waterstriders are good in detecting differences in iron and manganese, but seem to be poor in accumulating nickel and lead. Antlions are efficient in detecting differences in iron. Antlions and ants are effective in accumulating manganese; as well antlions are efficient in accumulating cadmium. Waterstriders are poor in accumulating lead, but antlions and ants are effective. - Waterstriders, dragon fly larvae, antlion larvae, and ants can be used as heavy metal indicators.

  19. Preparation of Dithizone Functionalized Polystyrene for Detecting Heavy Metal Ion

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hyeon Ho; Kim, Younghun [Kwangwoon University, Seoul (Korea, Republic of)


    Colorimetric sensors were usually used to detect specific metal ions using selective color change of solutions. While almost organic dye in colorimetric sensors detected single molecule, dithizone (DTZ) solution could be separately detected above 5 kinds of heavy metal ions by the change of clear color. Namely, DTZ could be used as multicolorimetric sensors. However, DTZ was generally used as aqueous type and paper/pellet-type DTZ was not reported yet. Therefore, in this work, polystyrene (PS) was prepared to composite with DTZ and then DTZ/PS pellet was obtained, which was used to selectively detect 10 kinds of heavy metal ions. When 10 ppm of Hg and Co ions was exposed in DTZ/PS pellets, clear color change was revealed. It is noted that DTZ/PS pellet could be used in detecting of heavy metal ion as dry type.

  20. Heavy metal pollution and genetic adaptations in ectomycorrhizal fungi




    Heavy metal toxicity is a strong trigger for evolutionary adaptation in terrestrial biota that colonise metalliferous soils. Here, I will focus on the occurrence of metal tolerance in ectomycorrhizal fungi, the predominant group of root symbionts of pioneer trees that try to colonise severely polluted sites. A considerable amount of literature exists on metal-tolerant plants, which is in sharp contrast to what we know about the tolerance in the fungal symbiotic partners that associate with th...

  1. Heavy Metals in ToxCast: Relevance to Food Safety (SOT) (United States)

    Human exposure to heavy metals occurs through food contamination due to industrial processes, vehicle emissions and farming methods. Specific toxicity endpoints have been associated with metal exposures, e.g. lead and neurotoxicity; however, numerous varieties of heavy metals hav...

  2. Perspectives in endocrine toxicity of heavy metals--a review. (United States)

    Rana, S V S


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

  3. Heavy metal contamination in the Western Indian Ocean (a review) (United States)

    Mamboya, F. A.; Pratap, H. B.; Björk, M.


    Western Indian Ocean Coast has many potential marine ecosystems such as mangrove, seagrass meadows, macroalgae, and coral reefs. It is largely unspoiled environment however, tourism and population growth in coastal urban centres, industrialization, are presenting a risk of pollutants input to the marine environment of the Western Indian Ocean. Mining, shipping and agricultural activities also input contaminants into the marine environment via runoff, vessel operations and accidental spillage. Heavy metals are among the pollutants that are expected to increase in the marine environment of the Western Indian Ocean. The increase in heavy metal pollution can pose a serious health problem to marine organism and human through food chain. This paper reviews studies on heavy metal contamination in the Western Indian Ocean. It covers heavy metal studies in the sediments, biota, particulates and seawater collected in different sites. In comparison to other regions, only few studies have been conducted in the Western Indian Ocean and are localized in some certain areas. Most of these studies were conducted in Kenyan and Tanzanian coasts while few of them were conducted in Mauritius, Somalia and Reunion. No standard or common method has been reported for the analysis or monitoring of heavy metals in the Western Indian Ocean.

  4. Heavy metal accumulation by carrageenan and agar producing algae

    Energy Technology Data Exchange (ETDEWEB)

    Burdin, K.S. [Moscow State Univ. (Russian Federation). Faculty of Biology; Bird, K.T. [North Carolina Univ., Wilmington, NC (United States). Center for Marine Science Research


    The accumulation of six heavy metals Cu, Cd, Ni, Zn, Mn and Pb was measured in living and lzophilized algal thalli. The agar producing algae were Gracilaria tikvahiae and Gelidium pusillum. The carrageenan producing macroalgae were Agardhiella subulata and the gametophyte and tetrasporophyte phases of Chondrus crispus. These produce primarily iota, kappa and lambda carrageenans, respectively. At heavy metal concentrations of 0.5 mg L{sup -1}, living thalli of Gracilaria tikvahiae generally showed the greatest amount of accumulation of the 6 heavy metals tested. The accumulation of Pb was greater in the living thalli of all four species than in the lyophilized thalli. Except for Agardhiella subulata, lyophilized thalli showed greater accumulation of Ni, Cu and Zn. There was no difference in heavy metal accumulation between living and lyophilized thalli in the accumulation of Cd. Manganese showed no accumulation at the tested concentration. There did not appear to be a relationship between algal hydrocolloid characteristics and the amounts of heavy metals accumulated. (orig.)

  5. New trends in removing heavy metals from wastewater. (United States)

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


    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.

  6. Roles of dynamic metal speciation and membrane permeability in metal flux through lipophilic membranes: General theory and experimental validation with nonlabile complexes

    NARCIS (Netherlands)

    Zeshi, Zhang; Buffle, J.; Leeuwen, van H.P.


    The study of the role of dynamic metal speciation in lipophilic membrane permeability in aqueous solution requires accurate interpretation of experimental data. To meet this goal, a general theory is derived for describing 1:1 metal complex flux, under steady-state and ligand excess conditions,

  7. Toxicity and metal speciation in acid mine drainage treated by passive bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Neculita, C.M.; Vigneaul, B.; Zagury, G.J. [Ecole Polytechnic, Montreal, PQ (Canada)


    Sulfate-reducing passive bioreactors treat acid mine drainage (AMD) by increasing its pH and alkalinity and by removing metals as metal sulfide precipitates. In addition to discharge limits based on physicochemical parameters, however, treated effluent is required to be nontoxic. Acute and sublethal toxicity was assessed for effluent from 3.5-L column bioreactors filled with mixtures of natural organic carbon sources and operated at different hydraulic retention times (HRTs) for the treatment of a highly contaminated AMD. Effluent was first tested for acute (Daphnia magna and Oncorhynchus mykiss) and sublethal (Pseudokirchneriella subcapitata, Ceriodaphnia dabia, and Lemna minor) toxicity. Acute toxicity was observed for D. magna, and a toxicity identification evaluation (TIE) procedure was then performed to identify potential toxicants. Finally, metal speciation in the effluent was determined using ultrafiltration and geochemical modeling for the interpretation of the toxicity results. The 10-d HRT effluent was nonacutely lethal for 0. mykiss but acutely lethal for D. magna. The toxicity to D. magna, however, was removed by 2 h of aeration, and the TIE procedure suggested iron as a cause of toxicity. Sublethal toxicity of the 10-d HRT effluent was observed for all test species, but it was reduced compared to the raw AMD and to a 7.3-d HRT effluent. Data regarding metal speciation indicated instability of both effluents during aeration and were consistent with the toxicity being caused by iron. Column bioreactors in operation for more than nine months efficiently improved the physicochemical quality of highly contaminated AMD at different HRTs.

  8. Precipitation of heavy metals in waste waters; Precipitacion de metales pesados en las aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Stutzel, K.; Peldszus, R.


    Heavy metals content in effluents is regulated due to their toxicity. To minimized them different precipitating agents are used. A comparison between some precipitating agents (the most common is H{sub 2}S) wit trimercapto-s-triazine (TMT 15) is shown. Solubility products of TMT 15 with divalent metals are very low: the precipitation with TMT 15 gives a heavy metal concentration in effluents below regulated levels. (Author)

  9. Removal of heavy metals from synthetic solution by electrocoagulation

    Directory of Open Access Journals (Sweden)

    Mohamed Ilou


    Full Text Available The objective of this work concerns the optimization of the operating conditions for the removal of heavy metals from synthetic solution by Electrocoagulation (EC. To reach this purpose, we prepared a synthetic wastewater containing certain heavy metals (Ni, Cu, Zn, Fe and Pb to study the influence of various parameters (conductivity, pH, time of electrolysis, current density and the initial concentration of the metal on the rate of removal of these metals. The results show that this rate of removal can reach 99.9 % in the following optimal conditions: pH included between 6 and 8 and a density of the current of 1~1.5A / dm2. This study shows that it is possible to remove metals in aqueous solution by the technique of electrocoagulation. 

  10. Magnetic fluctuations in heavy-fermion metals

    DEFF Research Database (Denmark)

    Mason, T.E.; Petersen, T.; Aeppli, G.


    Elastic and inelastic neutron scattering have been used to study the antiferromagnetic ordering and magnetic excitations of the U heavy-fermion superconductors UPd2Al3 and URu2Si2 above and below T-N. While both materials exhibit the coexistence of superconductivity and antiferromagnetic order, t...

  11. 100 - 107_Funtua_Heavy metals

    African Journals Online (AJOL)


    were washed with soap and rinsed with distilled water to avoid sample contamination(Awofolu,2005) . Five soil samples from each sampling location and depths were randomly collected and pooled together to form a composite from each of the sampling locations. The control samples were collected to validate the heavy.

  12. Heavy metal biosorption by bacterial cells

    NARCIS (Netherlands)

    Vecchio, A; Finoli, C; Di Simine, D; Andreoni, [No Value

    Microbial biomass provides available ligand groups on which metal ions bind by different mechanisms. Biosorption of these elements from aqueous solutions represents a remediation technology suitable for the treatment of metal-contaminated effluents. The purpose of the present investigation was the

  13. The environmental impact of gold mines: pollution by heavy metals (United States)

    Abdul-Wahab, Sabah; Marikar, Fouzul


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

  14. Clostridia initiate heavy metal bioremoval in mixed sulfidogenic cultures. (United States)

    Alexandrino, Maria; Costa, Rodrigo; Canário, Adelino V M; Costa, Maria C


    Sulfate reducing bacteria (SRB) are widely used for attenuating heavy metal pollution by means of sulfide generation. Due to their low metal tolerance, several SRB species depend on associated bacteria in mixed cultures to cope with metal-induced stress. Yet the identity of the SRB protecting bacteria is largely unknown. We aimed to identify these associated bacteria and their potential role in two highly metal-resistant mixed SRB cultures by comparing bacterial community composition and SRB activity between these cultures and two sensitive ones. The SRB composition in the resistant and sensitive consortia was similar. However, whereas the SRB in the sensitive cultures were strongly inhibited by a mixture of copper, zinc, and iron, no influence of these metals was detected on SRB growth and activity in the resistant cultures. In the latter, a Gram-positive population mostly assigned to Clostridium spp. initiated heavy metal bioremoval based on sulfide generation from components of the medium (mainly sulfite) but not from sulfate. After metal levels were lowered by the Clostridium spp. populations, SRB started sulfate reduction and raised the pH of the medium. The combination of sulfite reducing Clostridium spp. with SRB may improve green technologies for removal of heavy metals.

  15. Fluorescent and Colorimetric Electrospun Nanofibers for Heavy-Metal Sensing

    Directory of Open Access Journals (Sweden)

    Idelma A. A. Terra


    Full Text Available The accumulation of heavy metals in the human body and/or in the environment can be highly deleterious for mankind, and currently, considerable efforts have been made to develop reliable and sensitive techniques for their detection. Among the detection methods, chemical sensors appear as a promising technology, with emphasis on systems employing optically active nanofibers. Such nanofibers can be obtained by the electrospinning technique, and further functionalized with optically active chromophores such as dyes, conjugated polymers, carbon-based nanomaterials and nanoparticles, in order to produce fluorescent and colorimetric nanofibers. In this review we survey recent investigations reporting the use of optically active electrospun nanofibers in sensors aiming at the specific detection of heavy metals using colorimetry and fluorescence methods. The examples given in this review article provide sufficient evidence of the potential of optically electrospun nanofibers as a valid approach to fabricate highly selective and sensitive optical sensors for fast and low-cost detection of heavy metals.

  16. Dustfall Heavy Metal Pollution During Winter in North China. (United States)

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


    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.

  17. Phytochelatins and metallothioneins: roles in heavy metal detoxification and homeostasis. (United States)

    Cobbett, Christopher; Goldsbrough, Peter


    Among the heavy metal-binding ligands in plant cells the phytochelatins (PCs) and metallothioneins (MTs) are the best characterized. PCs and MTs are different classes of cysteine-rich, heavy metal-binding protein molecules. PCs are enzymatically synthesized peptides, whereas MTs are gene-encoded polypeptides. Recently, genes encoding the enzyme PC synthase have been identified in plants and other species while the completion of the Arabidopsis genome sequence has allowed the identification of the entire suite of MT genes in a higher plant. Recent advances in understanding the regulation of PC biosynthesis and MT gene expression and the possible roles of PCs and MTs in heavy metal detoxification and homeostasis are reviewed.

  18. Deena Weinstein, Heavy Metal: The Music and Its Culture


    Grassy, Elsa


    Au moment où la sociologue Deena Weinstein publie Heavy Metal : The Music and Its Culture, en 1991, le heavy metal fait l’objet de controverses très médiatisées aux États-Unis. Le procès de Judas Priest pour incitation au suicide vient de faire les gros titres, et tous les conservateurs du pays passent leurs journées à écouter des disques à l’envers, à la recherche de paroles sataniques. Le livre de Weinstein s’inspire de ce climat sulfureux qui entoure le heavy metal depuis ses débuts mais a...

  19. Electrodialytic Removal of Heavy Metals from Different Solid Waste Products

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Christensen, Iben Vernegren; Pedersen, Anne Juul


    A variety of heavy metal polluted waste products must be handled today. Electrochemical methods have been developed for remediation of polluted soil. One of the methods is the electrodialytic remediation method that is based on electromigration of heavy metal ions and ionic species within the soil...... matrix, and a separation of the soil and the process solutions, where the heavy metals are concentrated, with ion exchange membranes. For remediation of some soils, such as calcareous soils, it is necessary to add an enhancement solution. It was shown in a laboratory experiment that ammonium citrate...... could be used when removing Cu and Cr from a soil with 25% carbonates. The final concentrations of the elements were below the target values after the remediation. A question of whether the electrodialytic remediation method can be used for other waste products arose. Preliminary experiments showed...

  20. Effect of Heavy Metals in Plants of the Genus Brassica. (United States)

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


    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.

  1. Effect of heavy metals on growth and heavy metal content of Allium porrum L. and Pisum sativum L

    Energy Technology Data Exchange (ETDEWEB)

    Gruenhage, L.; Jaeger, H.J.


    The effects of cadmium, lead, zinc and copper, singly and in combination, on yield, heavy metal content and the mineral composition of Allium porrum L. and Pisum sativum L. have been investigated. The Cd, Pb, Zn and Cu concentrations of shoots and roots of Allium porrum increased with increasing heavy metal contamination of soil. However, no visible symptoms of heavy metal toxicity were recognized. The dry matter production was reduced as a function of heavy metal concentration and combination. The mechanisms of combinations were mostly synergistic. The correlation between pollutant contents (nmol/shoot) and yield was higher than the correlation between heavy metal concentrations of soil or shoots (ppm) and yield. Results of regression analyses showed that the inhibition of copper translocation caused by Cd, Pb and Zn was responsible for the yield depressions. The antagonism between Cd and N-deficiency showed that the level of N-supply was without negative effects on yield depressions of Pisum sativum caused by Cd. In contrast to this, the N-form played an important role in Cd-toxicity as the synergism between Cd and NH4 illustrated. K-deficiency as well as acidic nutrient solution (pH=4) diminished the root/shoot-barrier for Cd and therefore Cd-translocation from roots to shoots increased. Concerning calcium, magnesium and iron the decrease of ion uptake caused by Cd was statistically significant higher than yield depression.

  2. Characterization of a heavy metal translocating P-type ATPase gene from an environmental heavy metal resistance Enterobacter sp. isolate. (United States)

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


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

  3. Heavy metal pollution in coastal areas of South China: a review. (United States)

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


    Coastal areas of South China face great challenges due to heavy metal contamination caused by rapid urbanization and industrialization. In this paper, more than 90 articles on levels, distributions, and sources of heavy metals in sediments and organisms were collected to review the status of heavy metal pollution along coastal regions of South China. The results show that heavy metal levels were closely associated with local economic development. Hong Kong and the Pearl River Estuary were severely contaminated by heavy metals. However, concentrations of heavy metals in sediments from Hong Kong have continually decreased since the early 1990 s. High levels of heavy metals were found in biota from Lingdingyang in Guangdong province. Mollusks had higher concentrations of heavy metals than other species. Human health risk assessments suggested that levels of heavy metals in some seafood from coastal areas of South China exceeded the safety limit. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Using microbiological leaching method to remove heavy metals from sludge

    Directory of Open Access Journals (Sweden)

    Zhuyu Gu


    Full Text Available Microbial leaching is one of the most effective methods to remove heavy metals from sludge. In the conducted researches, the sludge samples were processed with Thiobacillus ferrooxidans and Thiobacillus thiooxidans obtained via cultivation, extraction and purification processes. Heavy metals such as Pb, Cd, Cu and Ni were leached from sludge by Thiobacillus ferrooxidans and Thiobacillus thiooxidans within different substrate concentration and pH value conditions. It is defined that from the point of view of economy and efficiency the optimal concentration of FeSO4.7H2O and sulfur for bio-leaching process was 0.2 g. The leaching rates of heavy metals such as Pb, Cd, Cu and Ni of the same concentration were 74.72%, 81.54%, 70.46% and 77.35% respectively. However, no significant differences depending on the pH value among the leaching rates were defined, even for the pH value of 1.5. Along with the removal of heavy metals from sludge, the organic matter, N, P, K were also leached to some extent. The losing rate of phosphorus was the highest and reached 38.44%. However, the content of organic matter, N, P, K in the processed sludge were higher in comparison with level I of the National Soil Quality Standards of China. Ecological risk of heavy metals in sludge before and after leaching was assessed by Index of Geo-accumulation (Igeo and comprehensive potential risk (RI. The results of research defined that the content of heavy metals in sludge meets the level of low ecological risk after leaching and their contents is lower in comparison with the National Agricultural Sludge Standard of China. Sludge leached by biological methods is possible to use for treatment for increasing soil fertility.

  5. Heavy metals accumulation affects bone microarchitecture in osteoporotic patients. (United States)

    Scimeca, Manuel; Feola, Maurizio; Romano, Lorenzo; Rao, Cecilia; Gasbarra, Elena; Bonanno, Elena; Brandi, Maria Luisa; Tarantino, Umberto


    Bone metabolism is affected by mechanical, genetic, and environmental factors and plays a major role in osteoporosis. Nevertheless, the influence of environmental pollution on the occurrence of osteoporosis is still unclear and controversial. In this context, heavy metals are the most important pollutants capable to affect bone mass. The aim of this study was to investigate whether heavy metals accumulation in bone tissues could be related to the altered bone metabolism and architecture of osteoporotic patients. To this end, we analyzed 25 bone head biopsies osteoporotic patients and 25 bone head biopsies of osteoarthritic patients. Moreover we enrolled 15 patients underwent hip arthroplasty for high-energy hip fracture or osteonecrosis of the femoral head as a control group. Bone head biopsies were studied by BioQuant-osteo software, scanning electron microscopy and Energy Dispersive X-ray microanalysis. We found a prevalence of lead, cadmium and chromium accumulation in osteoporotic patients. Noteworthy, high levels of sclerostin, detected by immunohistochemistry, correlate with the accumulation of heavy metal found in the bone of osteoporotic patients, suggesting a molecular link between heavy metal accumulation and bone metabolism impairment. In conclusion, the presence of heavy metals into bone shed new light on the comprehension of the pathogenesis of osteoporosis since these elements could play a non redundant role in the development of osteoporosis at cellular/molecular and epigenetic level. Nevertheless, in vivo and in vitro studies need to better elucidate the molecular mechanism in which heavy metals can participate to osteoporosis. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1333-1342, 2017. © 2016 Wiley Periodicals, Inc.

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

    Directory of Open Access Journals (Sweden)

    Ranhao Sun

    Full Text Available 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.

  7. Assessment of Heavy Metal Pollution in Topsoil around Beijing Metropolis (United States)

    Sun, Ranhao; Chen, Liding


    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

  8. Novel forward osmosis process to effectively remove heavy metal ions

    KAUST Repository

    Cui, Yue


    In this study, a novel forward osmosis (FO) process for the removal of heavy metal ions from wastewater was demonstrated for the first time. The proposed FO process consists of a thin-film composite (TFC) FO membrane made from interfacial polymerization on a macrovoid-free polyimide support and a novel bulky hydroacid complex Na4[Co(C6H4O7)2]·r2H2O (Na-Co-CA) as the draw solute to minimize the reverse solute flux. The removal of six heavy metal solutions, i.e., Na2Cr2O7, Na2HAsO4, Pb(NO3)2, CdCl2, CuSO4, Hg(NO3)2, were successfully demonstrated. Water fluxes around 11L/m2/h (LMH) were harvested with heavy metals rejections of more than 99.5% when employing 1M Na-Co-CA as the draw solution to process 2000ppm(1 ppm=1 mg/L) heavy metal solutions at room temperature. This FO performance outperforms most nanofiltration (NF) processes. In addition, the high rejections were maintained at 99.5% when a more concentrated draw solution (1.5M) or feed solution (5000ppm) was utilized. Furthermore, rejections greater than 99.7% were still achieved with an enhanced water flux of 16.5LMH by operating the FO process at 60°C. The impressive heavy metal rejections and satisfactory water flux under various conditions suggest great potential of the newly developed FO system for the treatment of heavy metal wastewater. © 2014 Elsevier B.V.

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  10. Geopolymer as an adsorbent of heavy metal: A review (United States)

    Ariffin, Nurliyana; Abdullah, Mohamad Mustafa Al Bakri; Zainol, Remy Rozainy Mohd Arif; Murshed, Mohd Fared


    This paper reviews about geopolymer based adsorbent focusing in the removal of heavy metal. The reviews include fundamental and types of material used in the formation of adsorbents. Geopolymer based adsorbent got attention recently due to its unique three-dimensional network structure, with fixed size pores and paths that allow certain heavy metal to pass through. Most materials that applied as adsorbent such as fly ash, metakaolin, kaolin and dolomite. A lot of sludge nowadays only dumped in the landfill which can be used as one of new materials as geopolymer based adsorbent.

  11. Improved inventory for heavy metal emissions from stationary combustion plants

    DEFF Research Database (Denmark)

    Nielsen, Malene; Nielsen, Ole-Kenneth; Hoffmann, Leif

    On behalf of the Ministry of the Environment DCE at Aarhus University annually reports heavy metals (HM) emissions to the UNECE CLRTAP (United Nations Economic Commission for Europe Convention on Long-Range Transboundary Air Pollution). This report presents updated heavy metal emission factors...... for stationary combustion plants and the corresponding improved emission inventories for the following HMs: Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pb), Selenium (Se) and Zinc (Zn). The report presents data for the year 2009 and time series for 1990...

  12. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    DEFF Research Database (Denmark)

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.


    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through...... the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even...

  13. Photoelectrochemical detection of toxic heavy metals

    CSIR Research Space (South Africa)

    Chamier, J


    Full Text Available atomic fluorescence spectroscopy (CVAFS). These techniques are sensitive and accurate in their detection of metals in the environment but are expensive to maintain, immobile and require sample preparation. Immobilisation of cation-selective flourophores...

  14. Heavy metal biosorption by bacterial cells

    Energy Technology Data Exchange (ETDEWEB)

    Vecchio, A.; Finoli, C.; Di Simine, D.; Andreoni, V. [Department of Food Science and Microbiology, State University, Milan (Italy)


    Microbial biomass provides available ligand groups on which metal ions bind by different mechanisms. Biosorption of these elements from aqueous solutions represents a remediation technology suitable for the treatment of metal-contaminated effluents. The purpose of the present investigation was the assessment of the capability of Brevibacterium sp. cells to remove bivalent ions, when present alone or in pairs, from aqueous solutions, using immobilized polyacrylamide cells of the microorganism in a flow-through system. The biosorption capacity of Brevibacterium cells was studied for lead, cadmium and copper. The metal cell binding capacity followed the order Cu > Pb > Cd, based on estimated q{sub max}. These values, expressed as mmol metal/g dry weight cells, were 0.54 for Cu, 0.36 for Pb and 0.14 for Cd. Polyacrylamide-gel immobilized cells were effective in Pb, Cu and Cd removal. Lead removal was not affected by the presence of Cd and Cu; lead instead inhibited Cd and Cu removal. The desorption of the metal, by fluxing a chelating solution, restored the metal binding capacity of the cells, thus affording the multiple use of the same biomass in the remediation treatment. (orig.) (orig.) With 5 figs., 4 tabs., 23 refs.

  15. Toxicity assessment of heavy metal mixtures by Lemna minor L. (United States)

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


    The discharge of untreated electroplating wastewaters directly into the environment is a certain source of heavy metals in surface waters. Even though heavy metal discharge is regulated by environmental laws many small-scale electroplating facilities do not apply adequate protective measures. Electroplating wastewaters contain large amounts of various heavy metals (the composition depending on the facility) and the pH value often bellow 2. Such pollution diminishes the biodiversity of aquatic ecosystems and also endangers human health. The aim of our study was to observe/measure the toxic effects induced by a mixture of seven heavy metals on a bioindicator species Lemna minor L. Since artificial laboratory metal mixtures cannot entirely predict behaviour of metal mixtures nor provide us with informations relating to the specific conditions in the realistic environment we have used an actual electroplating wastewater sample discharged from a small electroplating facility. In order to obtain three more samples with the same composition of heavy metals but at different concentrations, the original electroplating wastewater sample has undergone a purification process. The purification process used was developed by Orescanin et al. [Orescanin V, Mikelić L, Lulić S, Nad K, Rubcić M, Pavlović G. Purification of electroplating wastewaters utilizing waste by-product ferrous sulphate and wood fly ash. J Environ Sci Health A 2004; 39 (9): 2437-2446.] in order to remove the heavy metals and adjust the pH value to acceptable values for discharge into the environment. Studies involving plants and multielemental waters are very rare because of the difficulty in explaining interactions of the combined toxicities. Regardless of the complexity in interpretation, Lemna bioassay can be efficiently used to assess combined effects of multimetal samples. Such realistic samples should not be avoided because they can provide us with a wide range of information which can help explain

  16. Rhizobacteria of Populus euphratica Promoting Plant Growth Against Heavy Metals. (United States)

    Zhu, Donglin; Ouyang, Liming; Xu, Zhaohui; Zhang, Lili


    The heavy metal-resistant bacteria from rhizospheric soils of wild Populus euphratica forest growing in arid and saline area of northwestern China were investigated by cultivation-dependent methods. After screening on medium sparked with zinc, copper, nickel and lead, 146 bacteria strains with different morphology were isolated and most of them were found to be resistant to at least two kinds of heavy metals. Significant increase in fresh weight and leaf surface area of Arabidopsis thaliana seedlings under metal stress were noticed after inoculated with strains especially those having multiple-resistance to heavy metals such as Phyllobacterium sp. strain C65. Investigation on relationship between auxin production and exogenous zinc concentration revealed that Phyllobacterium sp. strain C65 produced auxin, and production decreased as the concentration of zinc in medium increased. For wheat seedlings treated with zinc of 2 mM, zinc contents in roots of inoculated plants decreased by 27% (P < 0.05) compared to the uninoculated control. Meanwhile, zinc accumulation in the above-ground tissues increased by 22% (P < 0.05). The translocation of zinc from root to above-ground tissues induced by Phyllobacterium sp. strain C65 helped host plants extract zinc from contaminated environments more efficiently thus alleviated the growth inhibition caused by heavy metals.

  17. Normal concentrations of heavy metals in autistic spectrum disorders. (United States)

    Albizzati, A; Morè, L; Di Candia, D; Saccani, M; Lenti, C


    Autism is a neurological-psychiatric disease. In the last 20 years we witnessed a strong increase of autism diagnoses. To explain this increase, some scientists put forward the hypothesis that heavy metal intoxication may be one of the causes of autism. The origin of such an intoxication was hypothesised to be vaccines containing thimerosal as antimicrobic preservative. This preservative is mainly made up of mercury. The aim of our research was to investigate the correlation between autism and high biological concentrations of heavy metals. Seventeen autistic patients, between 6 and 16 years old (average: 11.52 DS: 3.20) (15 males and 2 females), were investigated, as well as 20 non autistic subjects from neuropsychiatric service between 6 and 16 years (average: 10.41 DS: 3.20) (15 males and 2 females). In both groups blood, urine and hair samples were analysed trough means of a semiquantitative analysis of heavy metal dosing. The metals analysed were Lead, mercury, cadmium and aluminium, since their build-up may give both neurological and psychiatric symptoms. The comparison of the mean values of the concentrations between the groups, performed with ANOVA test, has shown no statistically relevant differences. There wasn't correlation between autism and heavy metal concentration.

  18. Albatross as Sentinels of Heavy Metal Pollution: Local and Global Factors (United States)

    Sentman, W.; Edwards, S. V.; Vo, A. E.; Bank, M. S.


    Heavy metal pollution in the Pacific Ocean has garnered significant attention in recent years, especially with regard to rising mercury emissions from Asia. Uncertainty exists over the extent to which mercury in biota may have resulted from increases in anthropogenic emissions over time. Albatrosses, including those inhabiting the North Pacific, are wide-ranging, long-lived, keystone, avian predators. Consequently, they serve as ideal sentinel species for investigating the effects of historical and contemporary pollution as well as local and global factors related to heavy metal bioaccumulation, exposure, and ecotoxicological risk. To date, high levels of mercury and lead have been documented in albatross species throughout the Pacific. To address biotic exposure to these multiple stressors, here we synthesize and conduct meta-analyses of total mercury, methylmercury, and lead exposure data in Black-footed albatross (Phoebastria nigripes) and Laysan albatross (Phoebastria immutabilis). Our approach uses data from the field and literature and for methyl mercury uses museum feathers spanning the past 130 years for Black-Footed albatross. We discuss the use and application of stable isotopes (δ15N and δ13C) as a way to control for temporal changes in trophic structure and diet and the importance of conducting speciation analyses, for mercury, to account for curator mediated inorganic mercury in older specimens. Our data showed higher levels of inorganic mercury in older specimens of Black-Footed albatross as well as two non-pelagic species (control samples) lacking historical sources of bioavailable mercury exposure, which suggests that studies on bioaccumulation should measure methylmercury rather than total mercury when utilizing museum collections. Additionally, at the local scale, previous research has reported that lead paint exposure from buildings was also an important environmental stressor for Laysan albatross, suggesting that albatross species face heavy

  19. Phytoremediation of heavy metal contaminated soil by Jatropha curcas. (United States)

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


    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.

  20. Using thermal evolution profiles to infer tritium speciation in nuclear site metals: an aid to decommissioning. (United States)

    Croudace, Ian W; Warwick, Phil E; Kim, Daeji


    Understanding the association and retention of tritium in metals has significance in nuclear decommissioning programs and can lead to cost benefits through waste reduction and recycling of materials. To develop insights, a range of metals from two nuclear sites and one non-nuclear site were investigated which had different exposure histories. Tritium speciation in metals was inferred through incremental heating experiments over the range of 20-900 °C using a Raddec Pyrolyser instrument. Systematic differences in thermal desorption profiles were found for nonirradiated and irradiated metals. In nonirradiated metals (e.g., stainless steel and copper), it was found that significant tritium had become incorporated following prolonged exposure to tritiated water vapor (HTO) or tritium/hydrogen gas (HT) in nuclear facilities. This externally derived tritium enters metals by diffusion with a rate controlled by the metal composition and whether the surface of the metal had been sealed or coated prior to exposure. The tritium is normally trapped in hydrated oxides lying along grain boundaries. In irradiated metals, an additional type of tritium can form internally through neutron capture reactions. The amount formed depends on the concentration and distribution of trace lithium and boron in the metal as well as the integrated neutron flux. Liberating this kind of tritium typically requires temperatures above 800 °C. The pattern of tritium evolution derived from simple thermal desorption experiments allows reliable inferences to be drawn on the likely origin, location, and phases that trap tritium. Any weakly bound tritium liberated at temperatures of ~100 °C is indicative of mostly HTO interactions in the metal. Any strongly bound tritium liberated over the range of 600-900 °C is indicative of neutrogenic tritium formed via neutron capture by trace Li and B. Neutron capture by lithium is likely to be more significant than for boron based on lithium's higher trace

  1. In situ reactive zone with modified Mg(OH)2 for remediation of heavy metal polluted groundwater: Immobilization and interaction of Cr(III), Pb(II) and Cd(II) (United States)

    Dong, Jun; Li, Bowen; Bao, Qiburi


    Mg(OH)2 dissolves slowly and can provide a long-term source of alkalinity, thus a promising alternative reagent for the in situ remediation of heavy metal polluted groundwater. However, the application of Mg(OH)2 on in situ reactive zone (IRZ) for heavy metal polluted groundwater has never been investigated. In this study, the behaviors of heavy metals in a Mg(OH)2 IRZ were monitored for 45 d. The heavy metals show a sequential precipitation by modified Mg(OH)2 due to the difference of Ksp. Column tests were conducted to investigate the temporal and spatial distribution of heavy metals in Mg(OH)2 IRZ and evaluate the stabilization effect for multi-heavy metal polluted groundwater. Experimental results indicate that there exist interactions between different heavy metals, and their zoning distribution is attributed either to the competitive adsorption onto porous media (control column) or to the sequential precipitation of heavy metal ions (IRZ column). In contrast with the control column, heavy metal contaminated area in Mg(OH)2 IRZ significantly shrinks. According to the chemical speciation analysis, when water containing Pb(II), Cd(II) and Cr(III) flows through Mg(OH)2 IRZ, exchangeable fraction of total concentration significantly reduce and the proportion of carbonate and Fe/Mn oxides fraction increase, indicating the decrease of their mobility and toxicity.

  2. Nanopolysaccharides for adsorption of heavy metal ions from water


    Liu, Peng


    With population expansion and industrialization, heavy metal has become one of the biggest and most toxic water pollutants, which is a serious problem for human society today. The aim of this work is to explore the potential of nanopolysaccharides including nanocellulose and nanochitin to remove metal ions from contaminated water. The above nano-polysaccharides are of interest in water purification technologies due to their high surface area, high mechanical properties, and versatile surface ...

  3. Heavy metals status of street roaming ruminants in north western ...

    African Journals Online (AJOL)

    The metals (Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn) levels were determined using atomic absorption spectroscopy (Alpha Star Model 4, Chem Tech Analytical) after acid digestion. The results showed that heavy metals concentration in cow blood ranged from 1.53+1.20 to 29.92+2.60 mg/L, goats from 3.11+0.02 to 17.57+0.05 ...

  4. Evidence of heavy metal accumulations in sooty terns

    Energy Technology Data Exchange (ETDEWEB)

    Stoneburner, D.L.; Patty, P.C.; Robertson, W.B.


    Research report: Sooty terns nesting at Dry Tortugas, Fla., were analyzed to determine levels of heavy metal bioaccumulation. Tissues, feces, and eggs were analyzed by neutron activation techniques. The highest levels of mercury were found in eggs, feathers, and blood; of cadmium in kidney and bone; and of selenium in kidney, liver, and feathers. The concentrations of metals found in the eggs indicate that they are being transmitted to succeeding generations. (29 references, 1 table)

  5. Heavy Metal Contaminated Soil Treatment: Conceptual Development (United States)


    scrubbers . Metal containing dusts may be recoveredý and could require landfill disposal’ or further treatment. 3.3.5 Flexibility. T,.sts have c:learly...extract metals from soils. The following are brief descriptions of these methods. Acids/ NH3 . Both strong and weak acid solutions have been...ammonia leaching and solvent extraction. The basic reactions are as follows.’ Cu + Cu(NH 3 )4 2 + 4NH40H- b2Ca( NH3 )* + 4H 2 O 4Cu( NH3 )* + Oz + H20

  6. Removal of heavy metal from industrial effluents using Baker's yeast (United States)

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


    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.

  7. Intraparticulate Metal Speciation Analysis of Soft Complexing Nanoparticles. The Intrinsic Chemical Heterogeneity of Metal-Humic Acid Complexes. (United States)

    Town, Raewyn M; van Leeuwen, Herman P


    The counterion condensation-Donnan (CCD) model for the electrostatic features of soft, charged nanoparticles (NPs) is applied to the determination of the intrinsic stability constants, K̅int, for inner-sphere Cd(II) and Cu(II) complexes with humic acid NPs. The novel CCD model accounts for the strong ion condensation potential for higher valency counterions within the intraparticulate double layer zone of the soft NP. The approach offers new insights into the intrinsic heterogeneity of the HA complexes, as revealed by the intraparticulate speciation as a function of the true degree of inner-sphere complexation, θM. The ensuing intrinsic heterogeneity parameters, Γ, for CdHA and CuHA complexes are in very good agreement with those obtained from dynamic electrochemical stripping chronopotentiometric measurements. The overall intraparticulate metal ion speciation is found to depend on θM: at low θM the strong inner-sphere complexes predominate whereas at higher θM values, electrically condensed M may be an equally significant or even larger fraction of the particle-associated M.

  8. Use of cestodes as indicator of heavy-metal pollution. (United States)

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


    Thirty snakehead fish, Channa micropeltes (Cuvier, 1831) were collected at Lake Kenyir, Malaysia. Muscle, liver, intestine and kidney tissues were removed from each fish and the intestine was opened to reveal cestodes. In order to assess the concentration of heavy metal in the environment, samples of water in the surface layer and sediment were also collected. Tissues were digested and the concentrations of manganese (Mn), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) were analysed by using inductively-coupled plasma mass-spectrometry (ICP-MS) equipment. The results demonstrated that the cestode Senga parva (Fernando and Furtado, 1964) from fish hosts accumulated some heavy metals to a greater extent than the water and some fish tissues, but less than the sediment. In three (Pb, Zn and Mn) of the five elements measured, cestodes accumulated the highest metal concentrations, and in remaining two (Cu and Cd), the second highest metal accumulation was recorded in the cestodes when compared to host tissues. Therefore, the present study indicated that Senga parva accumulated metals and might have potential as a bioindicator of heavy-metal pollution. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Donnan membrane speciation of Al, Fe, trace metals and REEs in coastal lowland acid sulfate soil-impacted drainage waters

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Adele M.; Xue, Youjia [School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Kinsela, Andrew S. [School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia); Institute for Environmental Research (IER), Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234 (Australia); Wilcken, Klaus M. [Institute for Environmental Research (IER), Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234 (Australia); Collins, Richard N., E-mail: [School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052 (Australia)


    Donnan dialysis has been applied to forty filtered drainage waters collected from five coastal lowland acid sulfate soil (CLASS) catchments across north-eastern NSW, Australia. Despite having average pH values < 3.9, 78 and 58% of Al and total Fe, respectively, were present as neutral or negatively-charged species. Complementary isotope dilution experiments with {sup 55}Fe and {sup 26}Al demonstrated that only soluble (i.e. no colloidal) species were present. Trivalent rare earth elements (REEs) were also mainly present (> 70%) as negatively-charged complexes. In contrast, the speciation of the divalent trace metals Co, Mn, Ni and Zn was dominated by positively-charged complexes and was strongly correlated with the alkaline earth metals Ca and Mg. Thermodynamic equilibrium speciation calculations indicated that natural organic matter (NOM) complexes dominated Fe(III) speciation in agreement with that obtained by Donnan dialysis. In the case of Fe(II), however, the free cation was predicted to dominate under thermodynamic equilibrium, whilst our results indicated that Fe(II) was mainly present as neutral or negatively-charged complexes (most likely with sulfate). For all other divalent metals thermodynamic equilibrium speciation calculations agreed well with the Donnan dialysis results. The proportion of Al and REEs predicted to be negatively-charged was also grossly underestimated, relative to the experimental results, highlighting possible inaccuracies in the stability constants developed for these trivalent Me(SO{sub 4}){sub 2}{sup −} and/or Me–NOM complexes and difficulties in modeling complex environmental samples. These results will help improve metal mobility and toxicity models developed for CLASS-affected environments, and also demonstrate that Australian CLASS environments can discharge REEs at concentrations an order of magnitude greater than previously reported. - Highlights: • CLASS discharge large amounts of metals and their speciation is poorly

  10. Elimination of heavy metals from leachates by membrane electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, R. [Technische Universitaet Dresden, Institut fuer Siedlungs- und Industriewasserwirtschaft, Mommsenstrasse 13, 01062 Dresden (Germany); Seidel, H. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Department Bioremediation, Permoserstrasse 15, D-04318 Leipzig (Germany); Rahner, D. [Technische Universitaet Dresden, Institut fuer Physikalische Chemie und Eektrochemie, Mommsenstrasse 13, D-01062 Dresden (Germany); Morgenstern, P. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Department Analytik, Permoserstrasse 15, D-04318 Leipzig (Germany); Loeser, C. [Technische Universitaet Dresden, Institut fuer Lebensmittel- und Bioverfahrenstechnik, Bergstrasse 120, D-01062 Dresden (Germany)


    The elimination of heavy metals from bioleaching process waters (leachates) by electrolysis was studied in the anode and cathode region of a membrane electrolysis cell at current densities of 5-20 mA/cm{sup 2} using various electrode materials. The leaching waters containing a wide range of dissolved heavy metals, were high in sulfate, and had pH values of approx. 3. In preliminary tests using a rotating disc electrode the current density-potential curve (CPK) was recorded at a rotation velocity of 0, 1000 and 2000 rpm and a scan rate of 10 mV/s in order to collect information on the influence of transport processes on the electrochemical processes taking place at the electrodes. The electrochemical deposition-dissolution processes at the cathode are strongly dependent on the hydrodynamics. Detailed examination of the anodic oxidation of dissolved Mn(II) indicated that the manganese dioxide which formed adhered well to the electrode surface but in the cathodic return run it was again reduced. Electrode pairs of high-grade steel, lead and coal as well as material combinations were used to investigate heavy metal elimination in a membrane electrolysis cell. Using high-grade steel, lead and carbon electrode pairs, the reduction and deposition of Cu, Zn, Cr, Ni and some Cd in metallic or hydroxide form were observed in an order of 10-40 % in the cathode chamber. The dominant process in the anode chamber was the precipitation of manganese dioxide owing to the oxidation of dissolved Mn(II). Large amounts of heavy metals were co-precipitated by adsorption onto the insoluble MnO{sub 2}. High-grade steel and to some extent lead anodes were dissolved and hence were proven unsuitable as an anode material. These findings were largely confirmed by experiments using combination electrodes of coal and platinized titanium as an anode material and steel as a cathode material.The results indicate that electrochemical metal separation in the membrane electrolysis cell can represent a

  11. Concentrations of heavy metals in effluent discharges downstream ...

    African Journals Online (AJOL)



    Jan 18, 2010 ... Various effluent samples were collected from their sources of discharge to the Ikpoba river in Benin. City, Edo State between September and October, 2008. Six heavy metals (cadmium, chromium, copper, nickel, lead and zinc) in the effluents and receiving water were analyzed by atomic absorption.

  12. Tree Leaves as Bioindicator of Heavy Metal Pollution in Mechanic ...

    African Journals Online (AJOL)

    Heavy metal accumulation in soils is of concern in agricultural production due to the adverse effects on food safety and marketability, crop growth due to phytotoxicity, and environmental health of soil organisms. Soil and plant samples were collected from mechanic village in Odeda local Government of Ogun State. The soil ...

  13. Assessment of Leaching of some Heavy Metals from Domestic ...

    African Journals Online (AJOL)

    The aim of this study is to assess the possible leaching of heavy metals from ceramic wares into different solutions. Ceramic spoon, pot, soup bowl, plate, mug and cup were leached in batch process using hot water and 4 % solutions of glacial acetic acid, HCl acid, NaOH and Na2CO3 respectively. Chromium, manganese ...

  14. Levels of heavy metals, total hydrocarbon and organic carbon ...

    African Journals Online (AJOL)

    The sediment samples of River Ethiope and Ikpoba River were collected and extracted using n-hexane (BDH, England) and the resulting extracts were read at 460nm with a spectrophotometer. The heavy metal analysis was carried out by using atomic absorption spectroscopy. The organic carbon was determined by ...

  15. Trend of Heavy Metal Concentrations in Lagos Lagoon Ecosystem ...

    African Journals Online (AJOL)


    of Physical and Chemical Oceanography, Bar Beach, Victoria Island, Lagos,. Nigeria. *Corresponding author. Email: Abstract. The distribution and occurrence of heavy metals in the sediment, water and benthic animals of the Lagos lagoon during the dry and rainy seasons were investigated over a ...

  16. Removal of nutrient and heavy metal loads from sewage effluent ...

    African Journals Online (AJOL)

    A deliberate lowering of effluent pH may increase root uptake thereby possibly reducing the clean-up time and improving effluent quality. There is potential for application of this technology in cities struggling with the cost of conventional sewage treatment. Keywords: bio-accumulation, bio-sorption, heavy metals, hydroponic, ...


    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...

  18. Determination of Some Heavy Metals in Selected Beauty and ...

    African Journals Online (AJOL)

    Determination of Some Heavy Metals in Selected Beauty and African Black Soaps Commonly Used in Kano – Nigeria. ... HNO3 and HCl (5:5:1 ratio) and analyzed for Ni, Cu, Fe, Co, Pb and Mn contents using air-acetylene flame atomic absorption spectrophotometer (Alpha 4) model by the standard calibration technique.

  19. Bait preference in basket trap fishing operation and heavy metal ...

    African Journals Online (AJOL)

    The bait preference of basket traps fishing operation and heavy metal contamination in the trap catches from Lagos Lagoon were carried out between January and June 2011. Sixty baskets traps were used for the fishing operation, twenty basket traps were baited each with soap, coconut and maize. Clibanarius africanus ...

  20. Safety Evaluation of Osun River Water Containing Heavy Metals and ...

    African Journals Online (AJOL)


    1Environmental, Analytical and Nutritional Chemistry Research Laboratory, Department of Chemical Sciences,. Osun State University ... Summary: This study evaluated the pH, heavy metals and volatile organic compounds (VOCs) in Osun river water. It also evaluated its ..... toxicity of pollutants. ALT and AST are markers of.

  1. Variations in the mineral composition and heavy metals content of ...

    African Journals Online (AJOL)

    The parts of Moringa oleifera were assessed for mineral composition and some heavy metal contents in this study, which included Ca, Mg, K, Na, Mn, Fe, Zn, Co, Se, Pb and Cd. Parts of the plant were obtained from Badagry in Lagos State, Nigeria. The samples were digested with HNO3 and analysed for the mineral ...

  2. INTRODUCTION Heavy metal pollution of water has become a ...

    African Journals Online (AJOL)

    major environmental problem almost since the advent of agricultural ... Nations state that monitoring eight elements in fish Hg, Cd, Pb, As, Cu, ..... Research J. Environ. Science, 3 (5):522-529. Staniskiene, B.; Matusevicius, P.; Budreckiene, R. and Skibniewska, K.A. 2006. Distribution of heavy metals in tissues of freshwater.

  3. A Review of Polycyclic Aromatic Hydrocarbons and Heavy Metal ...

    African Journals Online (AJOL)

    Michael Horsfall

    attention is focused on the reduction of anthropogenic pollutants such as industrial effluents, domestic sewage and mining wastes which are the main sources of heavy metal contaminants in the ocean. Concordantly, most of the human aquaculture activities such as the use of chemicals like feed additives, antibiotics, soil ...

  4. levels of heavy metals in gubi dam water bauchi, nigeria

    African Journals Online (AJOL)


    rivers to the ocean is in the form of particulate ... B.M. Wufem, Chemistry Programme, Abubakar Tafawa Balewa University, P.M.B. 0248, Bauchi. A.Q. Ibrahim ..... Chemistry. Wiley Interscience NY, p. 780. Sukiman, S.B., 1989. The determination of heavy metals in water, suspended materials and sediments from Langat River,.

  5. Heavy Metal Concentrations around a Hospital ...

    African Journals Online (AJOL)


    Basorun market Dumpsite and UI football field (Mean ± Standard deviation) and USEPA Upper Limit for Heavy Metals in Soil. Parameter. UCH. Bottom Ash. BASORUN. U.I.. USEPA. (Incinerator) ... unconnected with the fact that wastes are not allowed to be decomposed at the UCH incinerator, the point only serves as a ...

  6. Heavy Metals Levels in Fish Samples from North Central Nigerian ...

    African Journals Online (AJOL)



    Dec 24, 2014 ... liver of Tilapia zilli has the highest level of heavy metals with the concentration of ... This indicates that the fish samples could be used to monitor Mn and Cr pollution levels ... Many studies have implicated industrial or human.

  7. Heavy Metals Accumulation In Roadside Soil And Vegetation Along ...

    African Journals Online (AJOL)

    Levels of some heavy metals in soil and vegetation along a major highway in Libya were determined by Atomic Absorption Spectrophotometry. The concentrations of Pb, Cd, Ni, Zn, Cu, Cr and Mn in soil and vegetation all decreased with distance from the road, indicating their relation to traffic. The concentrations of the ...

  8. Heavy metal contamination of Clarias gariepinus from a lake and ...

    African Journals Online (AJOL)

    Heavy metal contamination of Clarias gariepinus from a lake and fish farm in Ibadan, Nigeria. FE Olaifa, AK Olaifa, AA Adelaja, AG Owolabi. Abstract. Adult Clarias gariepinus (African Catfish) were purchased from Eleiyele Lake and Zartech fish farm in Ibadan. Water samples were also collected in February (dry season) ...

  9. Determination of some heavy metals concentration in the tissues of ...

    African Journals Online (AJOL)

    Lead (Pb), Cobalt (Co), and Copper (Cu) concentrations were determined in bone, muscle and gill of two fish species (tilapia fish and cat-fish) collected from Tiga dam Kano, Nigeria during October, 2010. The mean concentrations of the heavy metals varied depending on the type of the tissue and fish species. Generally ...

  10. Assessment of heavy metals leachability from traditional clay pots ...

    African Journals Online (AJOL)

    The clay pots may transfer ones of their constituents into foodstuffs when they are coated with glazes which are said to contain heavy metals like Pb and Cd. This study was conducted to determine if traditional clay pots (unglazed) can also behave the same way. Leachate from the clay raw pulp material was initially ...

  11. Assessment of heavy metals leachability from traditional clay pots ...

    African Journals Online (AJOL)

    Abstract. The clay pots may transfer ones of their constituents into foodstuffs when they are coated with glazes which are said to contain heavy metals like Pb and Cd. This study was conducted to determine if traditional clay pots (unglazed) can also behave the same way. Leachate from the clay raw pulp material was initially ...

  12. Heavy Metals and Microbial Contaminants in a Commercial ...

    African Journals Online (AJOL)

    The heavy metal and microbial contaminants levels were evaluated in a commercial polyherbal product against the backdrop of reports of high levels of such contaminants in similar herbal products elsewhere in Nigeria, India and China. Atomic absorption spctrophotometric technique was used for the analysis of the herbal ...

  13. Microbial and heavy metal contamination of pineapple products ...

    African Journals Online (AJOL)

    The samples were tested for yeasts and moulds, total plate counts, Faecal coliforms, total coliforms, Escherichia coli, Salmonella, Shigella and Staphylococcus aureus using tested International Organization for Standardization (ISO) microbial determination methods. Quantitative determination of heavy metals: zinc, iron, ...

  14. Microbial and heavy metal contamination of pineapple products ...

    African Journals Online (AJOL)


    plate counts, Faecal coliforms, total coliforms, Escherichia coli, Salmonella, Shigella and Staphylococcus aureus using tested International Organization for Standardization (ISO) microbial determination methods. Quantitative determination of heavy metals: zinc, iron, lead, copper, cadmium and aluminium was carried out by ...

  15. Comparative study of Heavy Metals Distribution in a Mechanic ...

    African Journals Online (AJOL)

    A comparative study of heavy metals; Lead, Chromium, Arsenic, Nickel, Cadmium and Mercury distribution was carried out in Oluku and Otofure both in Metropolitan Benin City, Edo State Nigeria with the view to determine the level of concentration and contribution of each site investigated. Thirty eight (38) soil samples were ...

  16. Water quality characteristics and pollution levels of heavy metals in ...

    African Journals Online (AJOL)

    The main aim of this study was to assess the level of water quality of Lake Haiq, Ethiopia with respect to selected physical parameters and heavy metals. Parameters such as temperature, pH, turbidity, electrical conductivity and total dissolved solids were measured in situ. While total alkalinity, chloride, ammonia, nitrate and ...


    African Journals Online (AJOL)


    and minerals which is required for human health. They are made up of chiefly cellulose, hemicelluloses and pectin substances that give them their texture and ..... heavy Metals from Long-Range. Transboundary Air Pollution. Joint. Task Force on the Health Aspects of Long-Range Transboundary Air. Pollution, Geneva. 8.

  18. Assessment of Heavy Metal Content of Branded Pakistani Herbal ...

    African Journals Online (AJOL)

    Purpose: To investigate the heavy metals present in branded Pakistani herbal medicines used in the management of various human ailments. Method: The herbal dosage forms assessed were tablets, capsules and syrups. The samples were prepared for analysis by wet digestion method using nitric acid and perchloric acid ...

  19. Distribution of Heavy Metals in Organs of Freshwater Fishes from ...

    African Journals Online (AJOL)



    Dec 24, 2015 ... ABSTRACT. This work was carried out to investigate the accumulation profile of heavy metals in three fish species namely;. Albula vulpe, Clarias gariepinus and Tilapia zilli. The maximum mean concentration, 53.95 mg/kg was recorded for Mn in the liver. Cd, Cr and Pb, measured relatively lower ...

  20. heavy metal pollution asse al pollution assessment in the sediments

    African Journals Online (AJOL)


    ABSTRACT. Sediments were collected from Dumba and to assess the pollution statusof the sedim. Cadmium (Cd), Chromium (Cr), Copper (Cu. (Zn) and Arsenic (As) were analysed using concentration of heavy metals varies bet with standard average shale to assess pollution in Dumba and KwataYobe sedi assessed ...

  1. Heavy metal analyses and nutritional composition of raw and ...

    African Journals Online (AJOL)

    In view of this study and the importance of fish in human diet, it is recommended that biological monitoring of fishes meant for consumption from these two water bodies be carried out regularly to ensure human safety. Keywords: Nutritional composition, heavy metals, fresh water fishes, marine water fishes, lagoons ...

  2. Problem of landfilling environments pollution by heavy metals (United States)

    Zilenina, V. G.; Ulanova, O. V.; Begunova, L. A.


    The article discusses the problems of snow and soil pollution by heavy metals. The results of physical and chemical special features of the deposit environment are given. Also, the results of snow mantle research in Irkutsk are described. The problem of manganese degradation from electrochemical cells disposed in the SMW areas is being discussed.

  3. Electrodialytic Remediation of Heavy Metal Polluted Soil. An Innovative Technique

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik; Karlsmose, Bodil


    Electrodialytic remediationof heavy metal polluted soil is a newly developed method which combines the electrokinetic movement of ions in soil with the principle of electrodialysis. The method has prowen to work in laboratorscale and at presnet two types of pilot plants are build....

  4. Heavy metal pollution assessment in the sediments of lake Chad ...

    African Journals Online (AJOL)

    Sediments were collected from Dumba and KwataYobe of Lake Chad, Nigerian Sector.The aim was to assess the pollution statusof the sediments of the lake. The concentration of heavy metals, Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni), lead (Pb), Z (Zn) and Arsenic (As) were ...

  5. Heavy metals pollution at municipal solid waste dumpsites in Kano ...

    African Journals Online (AJOL)

    Soil samples collected from two major dumpsites each in Kano and Kaduna states were investigated for heavy metals pollution. Each of the dumpsite was divided into north, south, east and west. Four soil samples were collected at a depth of 0-15 cm from each part and pooled to form a composite sample. Soil samples from ...

  6. Phytoremediation of heavy metal contaminated soil using different ...

    African Journals Online (AJOL)

    A pot experiment was conducted to compare the plant biomass accumulation and heavy metal (HM) uptake by plant species grown in HM contaminated soils. The shoot dry weights of Eucalyptus camaldeulensis, Medicago sativum, and Brassica juncea grown in contaminated soils were reduced by 8, 5, and 3-fold, ...

  7. Suppressing Heavy Metal Leaching through Ball Milling of Fly Ash

    Directory of Open Access Journals (Sweden)

    Zhiliang Chen


    Full Text Available Ball milling is investigated as a method of reducing the leaching concentration (often termed stablilization of heavy metals in municipal solid waste incineration (MSWI fly ash. Three heavy metals (Cu, Cr, Pb loose much of their solubility in leachate by treating fly ash in a planetary ball mill, in which collisions between balls and fly ash drive various physical processes, as well as chemical reactions. The efficiency of stabilization is evaluated by analysing heavy metals in the leachable fraction from treated fly ash. Ball milling reduces the leaching concentration of Cu, Cr, and Pb, and water washing effectively promotes stabilization efficiency by removing soluble salts. Size distribution and morphology of particles were analysed by laser particle diameter analysis and scanning electron microscopy. X-ray diffraction analysis reveals significant reduction of the crystallinity of fly ash by milling. Fly ash particles can be activated through this ball milling, leading to a significant decrease in particle size, a rise in its BET-surface, and turning basic crystals therein into amorphous structures. The dissolution rate of acid buffering materials present in activated particles is enhanced, resulting in a rising pH value of the leachate, reducing the leaching out of some heavy metals.

  8. Bioaccumulation of Heavy Metals in Soil Invertebrates: Part 2 ...

    African Journals Online (AJOL)

    Bioaccumulation of Heavy Metals in Soil Invertebrates: Part 2: Uptake and Accumulation of Lead and Chromium by Achatina marginata (Linnaeus) and Lymnaea ... On the basis of elimination factors, the gut tissues of A. marginata gave low elimination factors, implying that these tissues in this species accumulated these ...

  9. Assessment of heavy metals in chicken feeds available in Sokoto ...

    African Journals Online (AJOL)



    Dec 8, 2014 ... Abstract. In the present work six metals (Cu, Pb, Zn, Cd, Mn and Ni) were analyzed for, using atomic absorption ... been detected in liver, kidney and muscle of broilers. (Coleman et al., 1992). Evidence of nickel deficiencies in chicks has been reported (NAS, 1980) ..... pollution on the levels of some heavy.

  10. Concentration of Heavy Metals in Drinking Water from Urban Areas ...

    African Journals Online (AJOL)


    such as temperature, conductivity, total dissolved solids (TDS), salinity, pH, and turbidity and ten heavy metals ... highlighted recently in Bangladesh where natural levels of arsenic in groundwater were found to be causing ... could be soil erosion, domestic waste from urban and rural areas and industrial wastes. So far, no ...

  11. Heavy Metal uptake Potentials of Pseudomonas aeruginosa and ...

    African Journals Online (AJOL)

    Uptake of heavy metals, silver and cadmium by Pseudomonas aeruginosa (a Gram negative bacterium) and Micrococcus luteus (a Gram positive bacterium) was investigated in Cadmium and Silver stock solution using ion selective electrodes. Silver and cadmium uptake by the two organisms was described by Langmuir ...

  12. Distribution of Heavy Metals in the Coastal Marine Surficial ...

    African Journals Online (AJOL)

    Concentrations of. Cd, Ni, and Pb in sediments above background level indicate that these sediments are polluted. Although the current concentration of most heavy metals in sediments is low, suggesting low levels of pollution in the study area, the increasing trend in dumping untreated wastes, driven by the demographic ...

  13. Heavy metal and proximate composition associated with the ...

    African Journals Online (AJOL)



    May 8, 2014 ... Changes in the heavy metal content and proximate composition during the 28 day composting of cassava peels used in the cultivation of the oyster mushrooms Pleurotus ostreatus strain EM-1 was studied. Significant dry weight variations of cellulose, hemicellulose and fat contents were observed from day ...

  14. Spatiotemporal Analysis of Heavy Metal Water Pollution in Transitional China

    Directory of Open Access Journals (Sweden)

    Huixuan Li


    Full Text Available China’s socioeconomic transitions have dramatically accelerated its economic growth in last three decades, but also companioned with continuous environmental degradation. This study will advance the knowledge of heavy metal water pollution in China from a spatial–temporal perspective. Specifically, this study addressed the following: (1 spatial patterns of heavy metal water pollution levels were analyzed using data of prefecture-level cities from 2004 to 2011; and (2 spatial statistical methods were used to examine the underlying socioeconomic and physical factors behind water pollution including socioeconomic transitions (industrialization, urbanization, globalization and economic development, and environmental characteristic (natural resources, hydrology and vegetation coverage. The results show that only Cr pollution levels increased over the years. The individual pollution levels of the other four heavy metals, As, Cd, Hg, and Pb, declined. High heavy metal water pollution levels are closely associated with both anthropogenic activities and physical environments, in particular abundant mineral resources and industrialization prosperity. On the other hand, economic development and urbanization play important roles in controlling water pollution problems. The analytical findings will provide valuable information for policy-makers to initiate and adjust protocols and strategies for protecting water sources and controlling water pollution; thus improving the quality of living environments.

  15. Determination of heavy metals in chinese prickly ash from different ...

    African Journals Online (AJOL)

    Purpose: To determine the heavy metal content of Chinese prickly ash (CPA) produced in various areas of China. Methods: CPA samples collected from different production areas in China were subjected to microwave digestion, and the contents of copper (Cu), nickel (Ni), chromium (Cr), lead (Pb), cadmium (Cd), arsenic.

  16. Physico-chemical parameters and heavy metal contents of Ibuya ...

    African Journals Online (AJOL)

    The physico-chemical parameters and heavy metal contents of Ibuya River were investigated between September 2012 and August 2013 from four stations using standard methods to etermine acceptable water quality standards and evaluate possible sustainability of a thriving fisheries cum tourist sport fishing venture.

  17. Isolation and characterization of heavy metal tolerant bacteria from ...

    African Journals Online (AJOL)

    Panteka stream is a flowing stream polluted with wastes from the activities of mechanics. Water samples collected at different points of the stream were analysed in order to determine the level of heavy metal contamination and bacteria diversity with the view to elucidating the bioremediating potentials of the bacteria isolates ...

  18. Environmental study of heavy metals influence on soil and Tansy ...

    African Journals Online (AJOL)

    ... work was to define the correlation between heavy metal (mercury, lead, cadmium, chrome and nickel) concentration changes (in soil, leaf, stem, root and essential oil in Tansy) and type and distance from source pollution. The concentration was monitored on different locations: 1) Chemical industry panevo (with accident ...

  19. Growth response and heavy metals tolerance of Axonopus affinis ...

    African Journals Online (AJOL)



    Dec 20, 2010 ... Different microorganisms have been used for bioremediation based on their resistance and ability to sequester heavy metals. ... agrochemicals and sewage sludge poses a major threat to the soil environment. ... DNA, the molecular target gene 16S rRNA was amplified using the universal primers set, fD1 ...

  20. Biomonitoring of some heavy metal contaminations from a steel ...

    African Journals Online (AJOL)

    Soil and plants growing in the vicinity of industrial areas display increased concentrations of heavy metals and give an indication of the environmental quality. The contamination source for aluminum, iron, nickel and lead in the Botanical garden of Mobarakeh Steel Company was recognized by analyzing the leaves and ...