Biofilms as bio-indicator for polluted waters?

The aim of this work was to investigate the heavy metal accumulation by natural biofilms living in the catchment area of the Tisza river in Hungary, as well as in biofilms cultivated in vitro. Laboratory tests have demonstrated that metals can be adsorbed on biofilms, depending on their concentration and on the availability of free sorptive places. Biofilms were cultivated in vitro in natural freshwater from the Saale river, Germany. After reaching the plateau phase, Cu was added to reach a concentration of 100 µg/L. An increase of its mass fraction in the biofilm was observed, which caused the decrease of the concentration in the water phase. Unfortunately, the reactor wall was also found to act as adsorbent for Cu. More detailed results of our in vitro experiments will be published in a forthcoming paper. Naturally grown biofilm samples from exposed as well as background places at the Hungarian rivers Szamos and Tisza were collected in 2000 and 2002 after the cyanide spill, and analysed using total reflection X-ray fluorescence analysis (TXRF). Metal mass fraction differences as high as two orders of magnitude were found between polluted and unpolluted (background) sampling points. Extremely high concentration values, e.g. 5600 µg/g Zn in biofilm, were found at highly polluted sampling points. This means an enrichment factor of ca. 10,000 compared to the water phase.     

Comparison of sediment pollution in the rivers of the Hungarian Upper Tisza Region using non-destructive analytical techniques

The rivers in the Hungarian Upper Tisza Region are frequently polluted mainly due to mining activities in the catchment area. At the beginning of 2000, two major mining accidents occurred in the Romanian part of the catchment area due to the failure of a tailings dam releasing huge amounts of cyanide and heavy metals to the rivers. Surface sediment as well as water samples were collected at six sites in the years 2000–2003, from the northeast-Hungarian section of the Tisza, Szamos and Túr rivers. The sediment pollution of the rivers was compared based on measurements of bulk material and selected single particles, in order to relate the observed compositions and chemical states of metals to the possible sources and weathering of pollution. Non-destructive X-ray analytical methods were applied in order to obtain different kinds of information from the same samples or particles. In order to identify the pollution sources, their magnitude and fate, complementary analyses were carried out. Heterogeneous particulate samples were analyzed from a large geographical territory and a 4-year time period. Individual particles were analyzed only from the “hot” samples that showed elevated concentrations of heavy metals. Particles that were classified as anthropogenic were finally analyzed to identify trace concentrations and chemical states of heavy metals.     

Isomerspecific determination of sorption/desorption,transformation and bioaccumulation of hexachlorocyclohexanes at the case site Bitterfeld with special regard to ageing effects

ABSTRACT

The production of hexachlorocyclohexanes (HCHs) at Bitterfeld, Germany, caused heavy contamination of sediments in the receiving waters and soils of riverbanks and floodplains of the Spittelwasser creek with adverse effects on the rivers Mulde and Elbe. This study was launched to investigate the isomer specific behaviour of aged and non-aged hexachlorocyclohexanes focusing on their transformation, sorption and bioaccumulation. Spiked residues of α- and γ-HCH were transformed in aerobic water/sediment systems, while no elimination was observed for β-, δ- and ε-HCH. In contrast, aged residues of all HCH isomers were entirely stable under these aerobic conditions, while under anaerobic conditions a significant transformation was found for all spiked HCH isomers. Desorption hysteresis was identified for all isomers. Ageing led to an increase in the binding strength of HCH isomers to sediment, indicated by elevated logK_OC-values and increased the persistence of HCH isomers in aerobic water/sediment systems. HCH bioaccumulated in benthic organisms of Spittelwasser creek and Schachtgraben canal. After their confluence the lipid normalised HCH concentrations in benthic organisms of Spittelwasser creek increased by a factor of 10, indicating the central role of HCH residues from the Schachtgraben canal for the HCH exposure of benthic biota in the aquatic system of the Spittelwasser creek.     

Determination and evaluation of natural radioactivity and heavy metal levels in the aquatic environment of trans-boundary rivers: Maritza,Tundja and Arda

The main problem in the trans-boundary river system is that heavy metal and radioactive pollution can cause long-term effects on ecosystems. Therefore the natural radioactivity and heavy metal levels in the Maritza, Tundja and Arda Rivers, common for Bulgaria and Turkey, were determined for 3 years period (2007–2010). Gross alpha, gross beta and total radium isotopes activities, uranium and heavy metal concentrations of the surface water of the rivers were investigated and also terrestrial gamma and gamma dose rate were measured. The results were compared with reported data from other countries of the world and the recommended international standards. The results gathered in this study may provide background data on the natural radioactive and heavy metal levels of these trans-boundary rivers.     

Characterization of anthropogenic sediment particles after a transboundary water pollution of river Tisza using synchrotron radiation

At the beginning of 2000, a major mining accident occurred in the Romanian part of the Tisza catchment area due to tailings dam failure releasing huge amounts of heavy metals to the river. Sediment samples were taken from the main riverbed at six sites in Hungary, on March 16, 2000. The objective of this work was to characterize the anthropogenic particles in river sediment previously selected by single-particle electron probe X-ray microanalysis (EPMA). The trace element composition, heterogeneity and heavy metal speciation of individual particles was studied using synchrotron radiation-based microbeam X-ray emission and absorption methods. Particles were selected only from samples regarded as polluted sediment. White-beam micro X-ray fluorescence (μ-XRF) allowed the quantitative determination of heavy metals such as cadmium in individual particles. The maximum observed concentration of cadmium (>700 μg/g) indicates that this highly toxic heavy metal is concentrated in individual anthropogenic particles. Using the combination of micro X-ray absorption near-edge structure and target-transformation principle component analysis, quantitative chemical speciation of copper and zinc was feasible on individual sediment particles. Heavy metals in most of the particles released from the pollution site remained in the sulfide form resulting in a limited mobility of these metals. Based on the information obtained using microanalytical methods, the estimation of the environmental mobility of heavy metals connected to microparticles becomes possible.     

Application of Thin-Window EPMA to Environmental Problems in Hungary

 The combination of single-particle analysis using thin-window EPMA and a reverse Monte Carlo quantification procedure has been proven to provide semi-quantitative elemental concentrations, including light elements. The capabilities of the method are demonstrated through three different environmental applications in Hungary. Lake Balaton is the largest lake in central Europe. It is suspected that the atmosphere is an important source of environmental deterioration of the Lake, relative to the pollutant supply by rivers and direct discharges. Thin-window EPMA results of around 25,000 individual particles indicated that the composition of the aerosol did not show characteristic seasonal variation, it was more correlated to the daily meteorological circumstances. A serious heavy metal pollution of the river Tisza occurred on 10 March 2000, from a mine-dumping site in Romania. Sediment samples were taken from the main riverbed at six sites, on 16 March 2000. In some of the samples, pyrite type particles were observed in high abundance, revealing their dumping-site origin. Biomass burning for energy production has been increased recently, mostly in households and for space heating. Fly-ash and bottom-ash samples were collected at a 600 kW heating plant at Sződliget during standard winter operation. Most particles contained over 65% of unburned organic substance. The concentrations of major elements were obtained for each individual particle using thin-window EPMA, providing accurate matrix composition for further μ-XRF investigations of the trace element composition.     

Polyethylene glycol functionalized Fe3O4@MIL-101(Cr) for the efficient removal of heavy metals from Ligusticum chuanxiong Hort

In recent years, the quality and safety issues of Chinese medicinal herbs have received great attention worldwide. Thereinto, heavy metal contamination has been one of the most serious concerns. Compared to the wide research in the analysis of heavy metals in medicinal herbs, the studies on the removal of heavy metals are relatively limited. In this study, polyethylene glycol functionalized Fe₃O₄@MIL-101(Cr) (Fe₃O₄@MIL-101(Cr)@PEG) was designed and synthesized to remove heavy metals from the decoction of Ligusticum chuanxiong Hort. The in-house fabricated Fe₃O₄@MIL-101(Cr)@PEG was characterized by a porous structure and a large specific surface area. Then, the efficiency of the material for the removal of five heavy metals was tested under optimal adsorption conditions. Meanwhile, the content of Senkyunolide A, Senkyunolide I, and Ferulic acid, the solid content, and the HPLC fingerprints similarity were used as the quality monitoring indicators of Ligusticum chuanxiong Hort decoction before and after the heavy metal removal. Results showed that the magnetic nanomaterial had excellent removal efficiency for As⁵⁺ (81.4 %), Cd²⁺ (88.19 %), and Pb²⁺ (83.79 %) and certain removal efficiency for Ni²⁺ (51.59 %) and Zn²⁺ (55.4 %) under the spiked concentration of 50 μg/mL. The content of Senkyunolide A, Senkyunolide I, and Ferulic acid were decreased by less than 8.00 % after the removal of heavy metals. Besides, the loss rate of solid content was only 0.18 %, and the fingerprints similarity was over 99.9 %. The results indicated that Fe₃O₄@MIL-101(Cr)@PEG could efficiently and selectively remove heavy metals from Ligusticum chuanxiong Hort without affecting its effective components. Due to the advantages of low-cost, simple manipulation, and good efficiency, the material can be recommended for heavy metals removal from the aqueous solutions of medicinal herbs, providing a new and promising application for the removal of exogenous contaminants in medicinal herbs.     

The anthropogenic transformation of the water bodies of the European North of Russia

Water bodies of the European North of Russia are classified according to the water contamination level. The high degree of contamination of particular river sections in the European North is shown to be caused by the accumulation of toxic heavy metal compounds and other pollutants. The values of the anthropogenicaltered natural background of water bodies were estimated. It was shown the content of phenol and of copper compounds, of iron and of nickel to exceed the maximum allowable concentrations dozens of times.     

Analysis of heavy metals and sulphur-rich compounds in the water moss Fontinalis antipyretica L. ex Hedw.

The water moss Fontinalis antipyretica has been investigated to estimate heavy metal pollution in the river Elbe (middle Germany). Procedures of plant separation, digestion as well as an analytical method for ICP-MS analyses have been evaluated. Reproducibility and accuracy have been demonstrated on BCR 61 (NIST) reference material and results have been compared with AAS and AES data. The distribution of heavy metals in different plant segments of indigenous material has been analyzed. Exposition of plant material in the river Elbe have shown no correlation between the heavy metal content in plants and that of water samples. Cd and Zn concentrations found in the plant material are significantly enriched relatively to control samples. To understand the sophisticated ‘real system’ experiments have been carried out under laboratory conditions to investigate induced sulphur-rich compounds in the presence of heavy metals using HPLC including on-line derivatization.     

Metal-metallothioneins like proteins investigation by heteroatom-tagged proteomics in two different snails as possible sentinel organisms of metal contamination in freshwater ecosystems

Metal speciation analysis in MLPs was carried out in two snails, Marisa cornuarietis and Pomacea bridgesi, in order to investigate them as possible sentinel organisms of heavy metal contamination. To carry out this study snails born in a non-contaminated environment were divided into two groups: a control group and a contaminated one with cadmium administered for 40 days. Subsequently, we investigated the speciation of the induced MLPs in exposed animals in relation to controls. In order to obtain the MLP fraction, cytosols from both snail species where subjected to size-exclusion fractionation, monitoring on-line the metal signal (Cd, Cu and Zn) by ICP-MS while protein elution was followed by on-line UV detection. MLP fraction was then separated by anion-exchange (AE)-FPLC using optimal chromatographic conditions for the separation of the different MLP isoforms in both snail species. Specific detection of separated metalloforms was carried out again by the hyphenation of the AE chromatographic system with ICP-MS. The determination of the amount of metal bound to MLPs was carried out by post-column isotope dilution analysis ICP-MS, finding that the snail M. cornuarietis accumulated higher concentrations of cadmium than P. bridgesi. Thus this first snail could therefore be a better candidate sentinel organism of pollution in natural waters. Identification and characterization of the isoforms separated in M. cornuarietis was carried out for the entire or intact isoforms by MALDI-TOF and then conventional triptic digestion was also carried out to identify the nature of the formed peptides. The presence identification of a MLP isoform of relatively low molecular weight in M. cornuarietis is reported.     

Analysis of total and dissolved heavy metals in surface water of a Mexican polluted river by total reflection X-ray fluorescence spectrometry

The present area of study is located in the Upper Course of the Lerma River (UCLR). The Lerma is one of the most important rivers of Mexico, where it drains highly populated and industrialized regions. The aim of the present study is to determine the heavy metal concentration of Cr, Mn, Fe, Cu and Pb in dissolved and total phases of the UCLR by means of Total Reflection X-ray Fluorescence Spectrometry (TXRF). The surface water samples were collected at 8 sites distributed following the stream flow direction of the river. Four sampling campaigns were carried out in each site in a 1-year period. A sample preparation method was applied in order to obtain the total and dissolved fraction and to destroy the organic matter. The total heavy metal average concentration decrease in the following order: Fe (2566 μg/L) > Mn (300 μg/L) > Cu (66 μg/L) > Cr (21 μg/L) > Pb (15 μg/L). In general, the heavy metal concentrations in water of the UCLR are below the maximum permissible limits.     

Heavy metal concentrations in soil and wild plants growing around Pb-Zn sulfide terrain in the Kohistan region, northern Pakistan

This study investigates the soil and wild plants of the Pb-Zn sulfide bearing mineralized zone of Indian plate (IP) in the Pazang and Lahor sites, Kohistan region, northern Pakistan. Soil and plants were analyzed for major cations (Na, K, Ca, Mg, Fe, Mn) and heavy metals (Pb, Zn, Cd, Cu, Cr, Ni, Co) concentrations by using atomic absorption spectrometer. Metal concentrations were used to quantify pollution contamination factors such as pollution load index (PLI) and plant bioaccumulation in soil and plants developed in mineralized zones in the Lahor and Pazang sites and an unmineralized zone (reference sites) of the Besham area. Soil and plants of the mineralized zone and surrounding areas have higher heavy metal (HM) contamination (P < 0.01) as compared to the reference site, which can be attributed to the dispersion of metals due to mining. Furthermore, in mineralized zones, the Lahor site was more contaminated than the Pazang site. This high HM contamination may pose potential threats to local communities of Kohistan region. The results also showed that plant species (Plectranthus rugosus, Rumex hastatus, Fimbristylis dichotoma, Heteropogon conturtus and Myrsine Africana) were the best HM accumulators.     

Transfer of selected heavy metals and radionuclides from calcareous peat to saw sedge (Cladium mariscus) in eastern Poland

Summary The level of artificial and natural radionuclide concentration as well as heavy metal content were determined in samples of saw sedge and peat collected in the Special Protection Area of peat bogs near Chelm (Poland). Gamma- and alpha-spectrometry with proper sample preparation were used to determine natural gamma-emitters, artificial ¹³⁷Cs and alpha-radiating plutonium (²³⁸Pu and ^239,240Pu). Non radioactive elements were determined by AAS. Rather low level of heavy metal concentration in all samples was found, however, the transfer factors were significant. Peat contamination with artificial radionuclides (¹³⁷Cs and plutonium) was low. Contrary, the concentration of these isotopes in saw sedge was higher than normally observed in non contaminated areas, what is a result of a significant transfer factor.     

Application of Short Sequential Extraction Procedure（SSEP） for the Determination of Zn, Cu, and Cd Contents in Riverbed Sludge in Hejiagou, Harbin, China

IntroductionThe environment is contaminated by high concen-trations of metals from different sources such as conta-minated soils[1—10], sediments[11—15], and sewage orindustrial sludge[16—20]. However, there has been noreport on the determination of he…     

Trace Metals in Microcrustaceans and Brazilian Waterweed from a Contaminated Chilean Wetland Using Total Reflection X-Ray Fluorescence Spectrometry

The trace element content of individual copepod specimens and of the Brazilian water weed (Egeria densa) from a metal-contaminated wetland in Southern Chile were determined using total reflection X-ray fluorescence spectrometry. Sampling of the water and the organisms was carried out at three sampling sites during 2004. Enhanced concentrations of dissolved Fe and Mn were found in the column water and in the pore water. The Fe content in the benthic copepods was significantly elevated compared to other aquatic organisms from different Chilean lakes. Regarding E. densa, healthy (green coloured) plants showed mass fractions of Fe, Mn, Ni, Cu and Zn which were typical for uncontaminated systems. In contrast, damaged (brownish coloured) plants exhibited very high Fe and Mn concentrations indicative of contamination or processes which changed the element load from the environment to the plant.     

The Analysis of Inorganic and Organic Pollutants in Soil with Special Regard to Their Bioavailability

Abstract

The most important inorganic pollutants in soil are the heavy metals. Problems related to the determination of the total and soluble content are discussed. Soluble contents are of interest in connection with studies about bioavailability. Because some of the heavy metals are essential for plant growth, most of the work about bioavailability has been done in the field of plant nutrition. Much less is known about the situation in polluted soils.

It was shown that neutral salt solutions which do not really change the pH of soil during the extraction procedure are best suited to define thresholds of excess. This is in contrast to much stronger extractants like EDTA or DTPA often proposed for the analysis of soils which are deficient in trace elements.

With three sets of experiments the correlation between the contents of cadmium, copper, nickel and zinc extracted by 0.1 M NaNO₃ (as an example of a neutral salt solution) and the plant response (phyto- or zootoxicity) are shown:

—pot experiments using soils which were contaminated by metal salt solutions

—pot experiments using soils from contaminated areas

—field studies in polluted areas. In these studies the aspect of heavy metal leaching was also considered.

The results were converted to indicative values in the Swiss Ordinance of Pollutants in the Soil. These indicative values derived from plant reactions were checked by the carbon mineralisation as an example of a soil microbiological process.

As it was found that organic pollutants are not easily taken up by plant roots the problem of bioavailability is much less important. However, the biodegradation and formation of metabolites has to be considered.     

Cadmium removal from single- and multi-metal (Cd + Pb + Zn + Cu) solutions by sorption on hydroxyapatite

Heavy metal contamination of waters and soils is particularly dangerous to the living organisms. Different studies have demonstrated that hydroxyapatite has a high removal capacity for divalent heavy metal ions in contaminated waters and soils. The removal of Cd from aqueous solutions by hydroxyapatite was investigated in batch conditions at 25+/-2 degrees C. Cadmium was applied both as single- or multi-metal (Cd + Pb + Zn + Cu) systems with initial concentrations from 0 to 8 mmol L(-1). The adsorption capacity of hydroxyapatite in single-metal system ranged from 0.058 to 1.681 mmol of Cd/g of hydroxyapatite. In the multi-metal system competitive metal sorption reduced the removal capacity by 63-83% compared to the single-metal system. The sorption of Cd by hydroxyapatite follows the Langmuir model. Cadmium immobilization occurs through a two-step mechanism: rapid surface complexation followed by partial dissolution of hydroxyapatite and ion exchange with Ca resulting in the formation of a cadmium-containing hydroxyapatite.     

The determination of heavy metal accumulation ratios in muscle, skin and gills of some migratory fish species by inductively coupled plasma-optical emission spectrometry (ICP-OES) in Beymelek Lagoon (Antalya/Turkey)

In this study, copper (Cu), zinc (Zn), manganese (Mn), iron (Fe), magnesium (mg), nickel (Ni), chrome (Cr), cobalt (Co) and boron (B) accumulation ratios of muscle, skin and gill of Striped seabream (Sparidae, Lithognathus mormyrus), Golden grey mullet (Mugilidae, Liza aurata), Thicklip grey mullet (Mugilidae, Chelon labrasus), Flathead mullet (Mugilidae, Mugil cephalus), Gilthead seabream (Sparidae, Sparus aurata) and Thinlip mullet (Mugilidae, Liza ramada) in Beymelek Lagoon (Antalya/Turkey) were investigated. The analyses of elements were performed with inductively coupled plasma-optic emission spectroscopy (ICP-OES) by using microwave digestion techniques. There were significant variations among heavy metal accumulation levels of the species and their tissues. The heavy metal concentrations found in tissues varied for Cu: 0.28-5.11, Zn: 4.27-339.76, Mn: 0.0-12.81, Fe: 3.25-117.73, Cr: 0.0-1.40, Co: 0.0-3.29 and Mg: 168.73-659.16 mg/kg wet weight. Ni and B were not detected in any tissues of the species. The heavy metal concentrations of fish in Beymelek Lagoon were lower than those of fish from other contaminated Mediterranean regions of Turkey. This research showed that heavy metal concentrations in muscles of investigated species were also lower than the maximum levels set by law.     

Heavy metal and trace element accumulation in muscle,liver and gills of the Pontic shad (Alosa immaculata Bennet 1835) from the Danube River (Serbia)

Pontic shad (Alosa immaculata Bennet 1835) is an anadromous species that lives in the heavily polluted north-western part of the Black Sea and migrates into the Danube River to spawn. To assess their heavy metal contamination levels, samples of Pontic shad were collected at 863 river kilometre of the Danube River. Muscle, liver and gill samples were prepared using microwave digestion, and the analysis of Al, As, Cd, Cu, B, Ba, Fe, Mg, Sr, Zn, Li, Co, Cr, Mn, Mo, Ni and Pb was performed with inductively-coupled plasma-optic emission spectroscopy (ICP-OES). Significant differences in concentrations of analyzed elements were observed among different tissues, as well as between the genders. Al, Sr, Ba, Mg, and Li had the highest concentrations in gills, while Cd, Cu, Zn, Fe and B were highest in the liver. While the muscle had the lowest concentrations of most of the analyzed elements, it had the highest concentration of As. This study has revealed that the concentrations of Cd and As in Pontic shad muscle tissue were above the maximum acceptable concentrations for human consumption, thus precautions need to be taken in order to prevent future heavy metal contamination.     

Microbial Sensing and Removal of Heavy Metals: Bioelectrochemical Detection and Removal of Chromium(VI) and Cadmium(II)

The presence of inorganic pollutants such as Cadmium(II) and Chromium(VI) could destroy our environment and ecosystem. To overcome this problem, much attention was directed to microbial technology, whereas some microorganisms could resist the toxic effects and decrease pollutants concentration while the microbial viability is sustained. Therefore, we built up a complementary strategy to study the biofilm formation of isolated strains under the stress of heavy metals. As target resistive organisms, Rhizobium-MAP7 and Rhodotorula ALT72 were identified. However, Pontoea agglumerans strains were exploited as the susceptible organism to the heavy metal exposure. Among the methods of sensing and analysis, bioelectrochemical measurements showed the most effective tools to study the susceptibility and resistivity to the heavy metals. The tested Rhizobium strain showed higher ability of removal of heavy metals and more resistive to metals ions since its cell viability was not strongly inhibited by the toxic metal ions over various concentrations. On the other hand, electrochemically active biofilm exhibited higher bioelectrochemical signals in presence of heavy metals ions. So by using the two strains, especially Rhizobium-MAP7, the detection and removal of heavy metals Cr(VI) and Cd(II) is highly supported and recommended.