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1.
Concentration of heavy metals and natural gross radioactivity were measured in the surface water and sediment of Hazar Lake (Elazi?, Turkey). Eight sampling sites were pre-defined in different locations of the lake. A preliminary study on heavy metals (Zn, Fe, Mn, Ni, Cu, Cr, Co and Pb), major elements (Na, K, Ca, Mg) concentrations and natural radioactivity related to 226Ra, gross-alpha and gross-beta radiations in the surface water and deep sediments were determined. The obtained results showed that, in general, the heavy metals (Zn, Fe, Mn, Ni, Cu and Pb) and major elements (Na, K, Ca, Mg) concentrations in water did not exceed WHO (World Health Organization, 1999), EC (Europe Community, 1998), EPA (Environment Protection Agency, 2002) and TSE-266 (Turkish Standard, 1997) guidelines. Generally, heavy metals and major elements concentration of the sediments were found decrease in sequence of Fe>Mg>Ca>Mn>Zn>Ni>Cr>Cu>Co>Pb. The results of this study indicated that a general absence of serious pollution in the Hazar Lake. The results obtained from the radioactivity determination indicate that the surface water radioactivity concentration of 226Ra, gross-alpha and gross-beta were ranging from 0.52+/-0.02 to 2.02+/-0.06 Bq/l and from 0.65+/-0.03 to 2.52+/-0.07 Bq/l and from 0.01+/-0.01 to 0.14+/-0.01 Bq/l, respectively. Deep sediment radioactivity concentrations of 226Ra is ranging from 0.07+/-0.03 to 0.32+/-0.07 Bq/g.  相似文献   

2.
Abstract

The binding site interactions of IHSS humic substances, Suwannee River Humic Acid, Suwannee River Fulvic Acid, Nordic Fulvic Acid, and Aldrich Humic Acid with various metals ions and a herbicide, methyl viologen were investigated using fluorescence emission and synchronous‐scan spectroscopy. The metal ions used were, Fe(III), Cr(III), Cr(VI), Pb(II), Cu(II) and Ni(II). Stern‐Volmer constants, KSV for these quenchers were determined at pH 4 and 8 using an ionic strength of 0.1M. For all four humic substances, and at both pH studied, Fe(III) was found to be the most efficient quencher. Quenching efficiency was found to be 3–10 times higher at pH 8. The bimolecular quenching rate constants were found to exceed the maximum considered for diffusion controlled interactions, and indicate that the fluorophore and quencher are in close physical association. Synchronous‐scan spectra were found to change with pH and provided useful information on binding site interactions between humic substances and these quenchers.  相似文献   

3.
Environmental Science and Pollution Research - Metal–organic frameworks (MOFs) are a polymer hybrid family of compounds comprising metal ions that have been deliberately incorporated in...  相似文献   

4.
Background, aim, and scope  Dye pollutants are a major class of environmental contaminants. Over 100,000 dyes have been synthesized worldwide and more than 700,000 tons are produced annually and over 5% are discharged into aquatic environments. The adsorption or sorption is one of the most efficient methods to remove dye and heavy metal pollutants from wastewater. However, most of the present sorbents often bear some disadvantages, e.g. low sorption capacity, difficult separation of spoil, complex reproduction, or secondary pollution. Development of novel sorbents that can overcome these limitations is desirable. Materials and methods  On the basis of the chemical coprecipitation of calcium oxalate (CaC2O4), bromopyrogallol red (BPR) was embedded during the growing of CaC2O4 particles. The ternary C2O4 2––BPR–Ca2+ sorbent was yielded by the centrifugation. Its composition was determined by spectrophotometry and AAS, and its structure and morphology were characterized by powder X-ray diffraction (XRD), laser particle-size analysis, and scanning electron microscopy (SEM). The adsorption of ethyl violet (EV) and heavy metals, e.g. Cu(II), Cd(II), Ni(II), Zn(II), and Pb(II) were carried out and their removal rate determined by spectrophotometry and ICP-OES. The adsorption performance of the sorbent was compared with powder activated carbon. The Langmuir isothermal model was applied to fit the embedment of BPR and adsorption of EV. Results  The saturation number of BPR binding to CaC2O4 reached 0.0105 mol/mol and the adsorption constant of the complex was 4.70 × 105 M–1. Over 80% of the sorbent particles are between 0.7 and 1.02 μm, formed by the aggregation of the global CaC2O4/BPR inclusion grains of 30–50 nm size. Such a material was found to adsorb cationic dyes selectively and sensitively. Ethyl violet (EV) was used to investigate the adsorption mechanism of the material. One BPR molecule may just bind with one EV molecule. The CaC2O4/BPR inclusion material adsorbed EV over two times more efficiently than the activated carbon. The adsorption of EV on the CaC2O4/BPR inclusion sorbent was complete in only 5 min and the sedimentation complete in 1 h. However, those of EV onto activated carbon took more than 1.5 and 5 h, respectively. The treatment of methylene blue and malachite green dye wastewaters indicated that only 0.4% of the sorbent adsorbed over 80% of color substances. Besides, the material can also adsorb heavy metals by complexation with BPR. Over 90% of Pb2+, and approximately 50% of Cd2+ and Cu2+, were removed in a high Zn2+-electroplating wastewater when 3% of the material was added. Eighty-six percent of Cu2+, and 60% of Ni2+ and Cd2+, were removed in a high Cd2+-electroplating wastewater. Discussion  The embedment of BPR into CaC2O4 particles responded to the Langmuir isothermal adsorption. As the affinity ligand of Ca2+, BPR with sulfonic groups may be adsorbed into the temporary electric double layer during the growing of CaC2O4 particles. Immediately, C2O4 2– captured the Ca2+ to form the CaC2O4 outer enclosed sphere. Thus, BPR may be released and embedded as a sandwich between CaC2O4 layers. The adsorption of EV on the sorbent obeyed the Langmuir isothermal equation and adsorption is mainly due to the ion-pair attraction between EV and BPR. Different from the inclusion sorbent, the activated carbon depended on the specific surface area to adsorb organic substances. Therefore, the adsorption capacity, equilibrium, and sedimentation time of the sorbent are much better than activated carbon. The interaction of heavy metals with the inclusion sorbent responded to their coordination. Conclusions  By characterizing the C2O4 2––BPR–Ca2+ inclusion material using various modern instruments, the ternary in situ embedment particle, [(CaC2O4)95(BPR)] n 2n, an electronegative, micron-sized adsorbent was synthesized. It is selective, rapid, and highly effective for adsorbing cationic dyes and heavy metals. Moreover, the adsorption is hardly subject to the impact of electrolytes. Recommendations and perspectives  The present work provides a simple and valuable method for preparing the highly effective adsorbent. If a concentrated BPR wastewater was reused as the inclusion reactant, the sorbent will be low cost. By selecting the inclusion ligand with a special structure, we may prepare some particular functional materials to recover the valuable substances from seriously polluted wastewaters. The recommended method will play a significant role in development of advanced adsorption materials. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

5.
Environmental Science and Pollution Research - Long-term exposure to environmental neurotoxic metals is implicated in the induction of dementia and cognitive decline. The present study aims to...  相似文献   

6.
Lake M?laren is the water supply and recreation area for more than 1 million people in central Sweden and subject to considerable environmental concern. To establish background data for assessments of contemporary levels of trophy and heavy metal pollution, sediment cores from the lake were analyzed. Diatom-inferred lake-water phosphorus concentrations suggest that pre-20th century nutrient levels in S?dra Bj?rkfj?rden, a basin in the eastern part of M?laren, were higher (c. 10-20 micrograms TP L-1) than previously assumed (c. 6 micrograms TP L-1). Stable lead isotope and lead concentration analyses from 3 basins (S. Bj?rkfj?rden, Gisselfj?rden and Ask?fj?rden) show that the lake was polluted in the 19th century and earlier from extensive metal production and processing in the catchment, particularly in the Bergslagen region. The lake has experienced a substantial improvement of the lead pollution situation in the 20th century following closure of the mining and metal industry. The lead pollution from the old mining industry was large compared to late-20th century pollution from car emissions, burning of fossil fuels and modern industries.  相似文献   

7.
Environmental Science and Pollution Research - Heavy metals is a collective term describing metals and metalloids with a density higher than 5 g/cm3. Some of them are essential...  相似文献   

8.
9.
Waste electrical and electronic equipment (e-waste) is the most rapidly growing waste stream in the world, and the majority of the residues are openly disposed of in developing countries. Waste printed circuit boards (WPCBs) make up the major portion of e-waste, and their informal recycling can cause environmental pollution and health risks. Furthermore, the conventional disposal and recycling techniques—mechanical treatments used to recover valuable metals, including copper—are not sustainable in the long term. Chemical leaching is rapid and efficient but causes secondary pollution. Bioleaching is a promising approach, eco-friendly and economically feasible, but it is slower process. This review considers the recycling potential of microbes and suggests an integrated bioleaching approach for Cu extraction and recovery from WPCBs. The proposed recycling system should be more effective, efficient and both technically and economically feasible.  相似文献   

10.
In this paper the time evolution of heavy metal concentration of Pb, Zn, Cd and Hg, in the sediments of the Bay of Cádiz (southwest of Spain) is studied during the past century, as a result of the industrial influence in the zone. The study has been performed using sedimentary profiles that have been extracted from the seabed. The measurement of 210Pb and 137Cs radionuclides has provided the dating of the sediment layers, up to a depth corresponding to the age of 115 years. The relative sedimentation rates obtained are around 0.2 cm/year. The 137Cs activity profile reflects the concentration of this radionuclide in the atmosphere and into aquatic systems during the second half of the twentieth century. This profile has been used to ratify the results provided by the 210Pb dating method.  相似文献   

11.
The impact of heavy metal levels (Cd, Cu, and Zn) on the reproductive parameters in natural populations of the Mediterranean killifish Aphanius fasciatus was monitored in four sites of the Tunisian coast. Our study covered a period of the reproductive cycle, from April to November 2009. The significantly higher levels of Cd, Cu, and Zn in the liver and gonads for both sexes (p?<?0.05) were observed in the most polluted site (Sfax coast). During the reproductive cycle of A. fasciatus, an unbalanced sex ratio in favor to females was observed for all the studied populations. The progression of the hepato- (HSI), gonadosomatic (GSI), and K-factor revealed a spatio-temporal variation between populations during the sampling period. Estradiol-17β amounts in the gonad tissues of females captured from the studied sites showed a significant difference, and the highest concentrations were noticed in the control site (Luza). Taking together, our data provide the first evidence of a physiologically stress and a disturbance of the reproductive status in natural populations of A. fasciatus.  相似文献   

12.
Environmental Science and Pollution Research - The heavy metal contamination of soil and groundwater is a serious threat to environment worldwide. The survival of human being primarily relies upon...  相似文献   

13.
Stream sediments from the mining and smelting district of Príbram, Czech Republic, were studied to determine the degree, sources and dispersal of metal contamination using a combination of bulk metal and mineralogical determinations, sequential extractions and Pb isotopic analyses. The highest metal concentrations were found 3-4 km downstream from the main polymetallic mining site (9800 mg Pb kg(-1), 26 039 mg Zn kg(-1), 316.4 mg Cd kg(-1), 256.9 mg Cu kg(-1)). The calculated enrichment factors (EFs) confirmed the extreme degree of contamination by Pb, Zn and Cd (EF>40). Lead, Zn and Cd are bound mainly to Fe oxides and hydroxides. In the most contaminated samples Pb is also present as Pb carbonates and litharge (PbO). Lead isotopic analysis indicates that the predominant source of stream sediment contamination is historic Pb-Ag mining and primary Pb smelting (206Pb/207Pb=1.16), while the role of secondary smelting (car battery processing) is negligible.  相似文献   

14.

Transition metal sulphide-loaded fly ash–based EU-12 photocatalysts were synthesized by sono-hydrothermal method followed by ion exchange. The composites were characterized by XRD, FESEM, DSC-TGA, Raman spectroscopy, and BET surface area analysis. The XRD results imply 76.39% crystallinity of EU-12 and morphological studies by FESEM, and TEM revealed the shape and size of EU-12, i.e. rod-shaped with size ranging from 5 to 200 nm. Band gap of all synthesized photocatalysts were found to be?≤?3.44 eV. The photoactivities of the photocatalysts were examined by degrading rhodamine B (RhB). The results indicated that metal sulphide/EU-12 composite had the strong photoactivity under visible light compared to dark environment. Furthermore, the efficiency of photocatalysts was determined in terms of degradation efficiency towards RhB which was found to be maximum of 98.62% for 0.2 M CdS/EU-12 at 2 gL?1 of catalyst dosage and 10 ppm of dye concentration within 3 h under visible light source of 200 W.

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15.
Plant communities on plots with different metal pollution levels were compared in a field study in order to select the most suitable plant species for the direction of secondary succession toward the targeted grassland vegetation. The vegetational succession showed a gradual increase in plant cover and the number of plant species on the less polluted locations. Two predominant grass species Calamagrostis varia and Sesleria caerulea were selected for phytostabilisation, but a severely reduced seed germination capacity obstructed their use in practice. The mycorrhizal succession showed a gradual replacement of non-mycorrhizal with mycorrhizal plant species. Similar levels of arbuscular mycorrhizal colonisation of a particular plant species may be developed within each growing season regardless of the levels of pollution, with the exception of vesicle/intraradical spore formation. The results suggest that lower overall mycorrhizal colonisation levels and increased vesicle/spore formation may be a part of a mycorrhizal strategy at the most polluted locations.  相似文献   

16.
Environmental Science and Pollution Research - Remediation materials are the most critical factors for in situ immobilization of soil contaminated by heavy metals. In this study, in order to...  相似文献   

17.
Environmental Science and Pollution Research - As an energy-intensive industry in China, it is critical to promote energy conservation and carbon emission reduction in the nonferrous metal industry...  相似文献   

18.
Concentrations of Fe, Mn, Ni, Cu, Cr and Zn in their total, silicate, organic, reactive and pyrite fractions were determined in soils collected from the Ortigueira saltmarshes (Esteiro, Ladrido and Mera, NW Iberian Peninsula), from sediments of the Landoi and Esteiro Rivers, and from sludge generated by a nearby dunite mine. The Esteiro saltmarsh presented clear enrichments of the four metals studied (first 10 cm), especially of Ni and Cr, whose concentrations were among the highest. It is proposed that the elevated Cr and Ni levels found in the Esteiro saltmarsh were derived from recent contributions of the mine, which are partially discharged into the Landoi River. Total Cu and Zn concentrations were lower than the corresponding ones for Cr and Ni. Under suboxic conditions, Ni, Cr, Cu and Zn were mainly associated with the reactive fraction. Under anoxic conditions, Cu and Ni were associated mainly with the pyrite phase. Pyritic Zn and Cr concentrations were relatively low and similar in all three saltmarshes; however, where anoxic-sulfidic conditions prevailed these two metals were mainly associated with the reactive and organic fractions.  相似文献   

19.
Uptake of Al, Cu, Fe, Mn, Ni, Ca, K, Mg, P, and S in Empetrum nigrum L. ssp. hermaphroditum Hagerup and Vaccinium myrtillus L. from Ni, Cu and SO2 contaminated sites in S?r-Varanger, northern Norway, were investigated. The primary objective was to study the effect of airborne heavy metal pollution on foliar element composition of these two dwarf shrubs. Ni distribution and availability in soils clearly indicate atmospheric deposition of Ni particulates in S?r-Varanger. Foliar Ni concentrations in E. hermaphroditum and V. myrtillus increased in relation to plant available Ni in corresponding soils. Leaves of E. hermaphroditum generally contained higher concentrations of Ni than leaves of V. myrtillus. Emissions influenced some features of leaf elemental composition of the two species in very different ways. In leaves of V. myrtillus, S increased in proportion to Ni and Cu, while levels of Mn decreased. In leaves of E. hermaphroditum, Fe increased in proportion to Ni and Cu, while levels of Ca decreased.  相似文献   

20.
Altindağ A  Yiğit S 《Chemosphere》2005,60(4):552-556
The accumulation of heavy metals (Cd, Pb, Hg and Cr) was measured by atomic absorption spectrophotometry in water, sediment, plankton and fish samples collected from Lake Bey?ehir, which is important bird nesting and visiting areas, and irrigation and drinking water sources. In Lake Bey?ehir, the accumulation orders of heavy metals were Cd>Pb>Cr>Hg in water, Pb>Cd>Cr>Hg in sediment, Pb>Cd>Cr>Hg in plankton, and Cd>Pb>Cr>Hg in the muscles and gills of chub, carp, tench, except for the muscle of pikeperch, in which it was Pb>Cd>Cr>Hg (P<0.05). In addition to this, accumulation orders of heavy metals in the food web was also found to be water>plankton>sediment>fish tissues, except for Cr. According to international criterias and Turkish regulations, heavy metal concentrations especially Cd and Pb in Lake Bey?ehir were markedly above the permissible levels for drinking water.  相似文献   

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