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Natural radionuclides in trees grown on a uranium mill tailings waste pile Полный текст
2011
Štrok, Marko | Smodiš, B (Borut) | Eler, Klemen
Objective The purpose of the study was to investigate natural radionuclide uptake and allocation by trees. Materials and methods Samples from six Scots pines (P. sylvestris), six Norway spruces (Picea abies) and one sycamore maple (Acer pseudoplatanus) tree, growing on the Boršt uranium mill tailings waste pile in Slovenia were collected. ²³⁸U, ²³⁰Th, ²²⁶Ra and ²¹⁰Pb activity concentrations in wood, shoots and 1-year-old needles or leaves were determined. Particular radionuclides were separated from the samples by appropriate radiochemical procedures and their activity concentrations measured with an alpha spectrometry system. In addition, concentration ratios for different plant parts were calculated. Results and conclusions Results showed that for all radionuclides, the highest activity concentrations were found in foliage, followed by shoots and wood. The activity concentrations in trees were from 0.01 to 5.4 Bq kg⁻¹ for ²³⁸U, 0.03-11.3 Bq kg⁻¹ for ²³⁰Th, 2.7-2,728 Bq kg⁻¹ for ²²⁶Ra and 5.1-321 Bq kg⁻¹ for ²¹⁰Pb. All activity concentrations were calculated on dry weight basis. The calculated concentration ratios were from 1.05E-5 to 5.39E-3 for ²³⁸U, 7.65E-6-2.88E-3 for ²³⁰Th, 3.10E-4-3.16E-1 for ²²⁶Ra and 6.70E-4-4.22E-2 for ²¹⁰Pb.
Показать больше [+] Меньше [-]Monuments as sampling surfaces of recent traffic pollution Полный текст
2011
Rampazzi, Laura | Giussani, Barbara | Rizzo, Biagio | Corti, Cristina | Pozzi, Andrea | Dossi, Carlo
Background, aim and scope A new approach towards monuments, considering them as a passive sampler of pollution, is presented. Cultural Heritage objects suffer daily the damages of environmental pollution, especially in those areas interested by heavy traffic. Since monuments undergo only periodic conservation or maintenance works, surfaces are able to accumulate atmospheric deposit and to record changes in its composition. An optimised analytical protocol was developed in order to quantify platinum and rhodium at trace level on surfaces. The two elements have become tracers of automobile emissions in recent years, since the introduction of catalytic converters, and could have catalytic effects on the decay reactions of natural and artificial stone materials. As a first case study, the cement mortar surfaces of a twentieth century monument, the Camerlata Fountain, in Como (Italy) were investigated. Materials and methods The surfaces of the monument were scraped in areas both exposed to atmosphere and sheltered by the architectural elements of the building. The powders were dissolved by microwave-assisted mineralisation with a solution of HCl and HNO₃. The solution was filtered, irradiated and analysed by adsorptive cathodic stripping voltammetry. The powders were also analysed by infrared spectroscopy and X-ray diffraction in order to determine the chemical and mineralogical composition. Results and discussion An analysis protocol was set up considering the matrix effect and the expected low concentrations of the two metals. The results enlightened variable concentration values and distribution areas of platinum (0.013-45 μg/kg) and rhodium (0.55-274.4 μg/kg), suggesting the ability of artificial stone surfaces to accumulate the two elements. The sample chemical and mineralogical composition was consistent with a typical cement plaster interested by decay phenomena. Conclusions This work investigated the relation between Cultural Heritage and pollution by another point of view. The analytical protocol presented in this paper was effective in determining platinum and rhodium in traces on the investigated stone surfaces with negligible matrix effects. Recommendation and perspectives The presence of platinum and rhodium on monument surfaces should be of significant interest when planning Cultural Heritage conservation. A better knowledge of the role of the two metals in decay phenomena could impact in a positive way artwork conservation.
Показать больше [+] Меньше [-]Spectrofluorimetric study of the ageing of mixtions used in the gildings of mediaeval wall paintings Полный текст
2011
Mounier, Aurélie | Belin, Colette | Daniel, Floréal
Introduction In the Middle Ages, we could find gildings on mural paintings. Gold, silver or tin leaves were applied according to distemper or mixtion technique. For the first one, a binder as glue is necessary, and for the second, a lipidic binder is used to stick the metallic leaf. Studies of gildings materials characterization show that the mixtion technique, with a mordant, is the most common. Linseed oil seems to be the binder used. It is always mixed with a siccative agent as lead. Because of bad conditions of conservation, the gildings do not resist anymore, only remain traces of metal or the adhesive under-layer. Thanks to the binder fluorescence, we can nowadays detect ancient gildings. Objective The purpose of this paper is to study the degradation of the linseed oil, generally mixed with lead white to give a mordant for the metallic leaf, by spectrofluorimetry. Materials and methods To understand in situ fluorescence, gildings recreations, linseed oil and lead white are aged in hygro-thermal and ultraviolet (UV) light (313 nm) climatic rooms and under UV irradiation. Irradiation wavelengths are chosen according to the maximum of absorption of linseed oil and the bibliography (296, 313 and 366 nm = mercury bands). Results In comparison with results (in situ UV lamp, spectrofluorimetry), excitation wavelength chosen is 366 nm. Irradiations at 366 nm of linseed oil and linseed oil mixed with lead white show the most degrading effect in the fluorescence to the big wavelength. Lead white plays an important siccative role; it increases the intensity fluorescence and accelerates the drying of linseed oil. This study also allows to show that 366 nm wavelength is good for the in situ observation.
Показать больше [+] Меньше [-]Investigation of ZnO nanoparticles' ecotoxicological effects towards different soil organisms Полный текст
2011
Manzo, Sonia | Rocco, Annamaria | Carotenuto, Rita | De Luca Picione, Fabiano | Miglietta, Maria Lucia | Rametta, Gabriella | Di Francia, G (Girolamo)
Introduction Nanomaterials have widespread applications in several industrial sectors. ZnO nanoparticles (NPs) are among the most commonly used metal oxide NPs in personal care products, coating and paints. However, their potential toxicological impact on the environment is largely unexplored. Materials and methods The aim of this work was to evaluate whether ZnO nanoparticles exert toxic and genotoxic effects upon terrestrial organisms: plants (Lepidium sativum, Vicia faba), crustaceans (Heterocyipris incongruens), insects (Folsomia candida). To achieve this purpose, organisms pertaining to different trophic levels of the soil ecosystem have been exposed to ZnO NPs. In parallel, the selected soil organisms have been exposed to the same amount of Zn in its ionic form (Zn²⁺) and the effects have been compared. Results The most conspicuous effect, among the test battery organisms, was obtained with the ostracod H. incongruens, which was observed to be the most sensitive organism to ZnO NPs. The root elongation of L. sativum was also mainly affected by exposure to ZnO NPs with respect to ZnCl₂, while collembolan reproduction test produced similar results for both Zn compounds. Slight genotoxic effects with V. faba micronucleus test were observed with both soils. Conclusion Nanostructured ZnO seems to exert a higher toxic effect in insoluble form towards different terrestrial organisms with respect to similar amounts of zinc in ionic form.
Показать больше [+] Меньше [-]Simulation of the influence of industrial wastewater on a municipal sewage treatment plant--a case study Полный текст
2011
Rédey, Ákos | Somogyi, Viola | Ányos, József | Domokos, Endre | Thury, Péter | Yuzhakova, Tatiana
Purpose Industrial wastewater flow caused operational difficulties in the wastewater treatment plant in Debrecen, Hungary. Bioaugmentation was successfully applied to maintain effluent quality in the periods when wastewater of high starch content was accepted, but, at the end of 2008, the nitrification capacity of the plant decreased considerably due to improperly pre-treated pharmaceutical wastewater. Methods and material Dynamic simulations were carried out in a prototype programme developed by the Environmental Expert System Research Group at the University of Pannonia, Hungary. Several parameters for heterotrophic biomass were adjusted in function of time, and the specific growth rate of autotrophic biomass was altered in function of time and temperature in order to describe the effects of inoculation and toxic influence. Simulations were carried out with both constant and adjusted parameters. Results Though results on effluent COD of the different modelling versions were similar, the ammonia concentration fitted the measured data only when modified parameters were used. The study revealed that the autotrophic biomass had slowly adapted to the toxic compound. Different control strategies of aeration and decreased excess sludge removal rate were tested to enhance the nitrification in the critical time intervals. The amount of ammonia and inorganic nitrogen decreased in all cases while the oxygen demand increased to a maximum of 10.1%. Conclusions Reducing excess sludge removal rate gave satisfactory results even without changing aeration. Further improvement could be achieved by introducing aeration into the post-denitrification reactor. The combination of the two modifications can compensate for the effect caused by toxicity.
Показать больше [+] Меньше [-]Composition changes in the cuticular surface lipids of the helophytes Phragmites australis and Juncus effusus as result of pollutant exposure Полный текст
2011
Macherius, André | Kuschk, Peter | Haertig, Claus | Moeder, Monika | Shtemenko, Natalia I. | Bayona, Antonio Heredia | Guerrero, José A Heredia | Gey, Manfred
Aim of the study Helophytes like rush and reed are increasingly used for phytoremediation of contaminated water. This study characterises the response of rush and reed plants to chemical stressors such as chlorobenzene, benzene and methyl-tert-butyl ether. The extractable wax layer of the cuticle was chosen for detailed investigations due to its multiple, particularly, protective functions for plants and its easy availability for analysis. Methods The chemical composition of the cuticle wax layer of reed and rush was studied in dependence on chemical stress caused by contaminated water under wetland cultivation conditions. The lipid layer of leaves was extracted, derivatised and investigated by GC-MS using retention time locking and a plant-specific data base. Results In case of rush, a remarkable increase of the total lipid layer and a prolongation of the mean chain length resulted as response on a chlorobenzene exposure. The significant difference in the substance profiles of exposed plants and controls could be confirmed by multivariate data analysis. The lipid layer of reed was not changed significantly when the plants were exposed to water polluted with benzene and methyl-tert-butyl ether. However, scanning electron microscopic images of the exposed reed leaves indicated alterations in the crystal structure of their wax surface. Conclusion The composition and morphology of cuticular waxes indicated the plants' response to chemical stress very sensitively thus, changes in the wax layer could be used as an indication for growing in a contaminated area.
Показать больше [+] Меньше [-]Detection of naproxen and its metabolites in fish bile following intraperitoneal and aqueous exposure Полный текст
2011
Brozinski, Jenny-Maria | Lahti, Marja | Oikari, Aimo | Kronberg, Leif
Purpose The anti-inflammatory drug naproxen (NPX) has been found as a micropollutant in river water downstream the discharge points of wastewater treatment plants (WWTP). In this study, rainbow trout (Oncorhynchus mykiss) was exposed to NXP and the uptake and metabolism of the drug was studied. Methods Following exposure through intraperitoneal injection (i.p., 0.5 mg NPX/100 g fish biomass) and through water (1.6 μg L⁻¹), the bile was collected and analyzed with various LC-MS/MS methods. The identification of the formed metabolites in i.p. injected fish was based on the exact mass determinations by a time-of-flight mass analyzer (Q-TOF-MS) and on the studies of fragments and fragmentation patterns of precursor ions by an ion trap mass analyzer (IT-MS). Results No matter the exposure route, the main metabolites were found to be acyl glucuronides of NPX and of 6-O-desmethylnaproxen. Also, unmetabolized NPX was detected in the bile. The total bioconcentration factors (BCFtotal₋bile) of NPX and the metabolites in the bile of fish exposed through water ranged from 500 to 2,300. Conclusion The findings suggest that fish living downstream WWTPs may take up NPX and metabolize the compound. Consequently, NPX and its metabolites in bile can be used to monitor the exposure of fish to NPX.
Показать больше [+] Меньше [-]XAS study of lead speciation in a central Italy calcareous soil Полный текст
2011
Comaschi, Tatiana | Meneghini, Carlo | Businelli, Daniela | Mobilio, S. | Businelli, Mario
Purpose The Pb absorption processes on a heavy textured calcareous soil, typical of central Italy, were studied using synchrotron X-ray absorption spectroscopy (XAS) in order to probe, at molecular scale, the structure and chemical nature of Pb in contaminated soils and achieve precise description of Pb ions localization into these contaminated soils. Materials and methods In order to distinguish the role of the different components of soils in Pb retention, samples were prepared from the original soils removing the carbonate fractions, the organic matter, the metal oxides, or selecting the clay fractions. Then these samples were fortified with Pb simulating the natural interactions processes of heavy metal solutions with soils. The quantitative analysis of near edge (XANES) as well extended (EXAFS) regions of Pb LIII edge absorption spectra, in comparison with Pb XAS data of selected reference compounds, allowed the precise determination of local structure and chemical environment of Pb ions in these soil samples. Results Four components were individuated as the major responsible of Pb retention in calcareous soils: the carbonates, the metal oxide surfaces, the organic matter, and the colloidal inorganic surfaces containing clay components. The structural analysis suggests that, within these experimental conditions, the Pb adsorbed on the soil is generally present as Pb hydroxide with poor crystallization degree. However, the presence of carbonates (CaCO₃) induces the co-precipitation of PbCO₃-like phases with some degree of crystallinity.
Показать больше [+] Меньше [-]Genetic ecotoxicology of asbestos pollution in the house mouse Mus musculus domesticus Полный текст
2011
Ben-Shlomo, Rachel | Shanas, Uri
PURPOSE: We tested the genetic diversity in wild mice (Mus musculus domesticus) inhabiting the asbestos-polluted area as a model for the long-term mutagenic effect of asbestos. Hazardous effects of deposited asbestos persist in the environment because of low rate of fiber disintegration. The upper layers of the soil in the vicinity of a former asbestos factory are nearly “saturated” with asbestos fibers and dust. Natural populations of mice dwell in this area and are constantly exposed to asbestos fibers. METHODS: We measured the microsatellites genetic diversity of wild mice (Mus musculus domesticus) inhabiting the asbestos-polluted area as a model for the long-term mutagenic effect of this environmental toxin. RESULTS: The six tested microsatellites were highly polymorphic, revealing 111 different alleles for the two sampled populations. Effective number of alleles was slightly higher in the polluted population relative to the control population, while observed heterozygosity was lower. The chromatographic profile of the polluted population exhibited a significantly higher number of bands, probably resulting from somatic mutations, in addition to the ordinary microsatellite band profiles. CONCLUSIONS: Long-term exposure to asbestos fibers significantly elevates the level of somatic mutations. It also leads to a relatively high level of observed homozygosity, a phenomenon that may be associated with loss of heterozygosity. Based on the mice population, our data suggest elevated health risks for humans living in an asbestos-polluted area.
Показать больше [+] Меньше [-]Organic matter compounds as source indicators and tracers for marine pollution in a western Mediterranean coastal zone Полный текст
2011
Amorri, Jalila | Geffroy-Rodier, Claude | Boufahja, Fehmi | Mahmoudi, Ezzeddine | Aïssa, Patricia | Ksibi, Mohamed | Amblès, André
INTRODUCTION: Complex organic compounds found in oil and sediments linked with a particular source (such as algae, bacteria or vascular plants) are defined as biomarkers and are useful dating indicators in organic geochemistry. METHODS AND RESULTS: This paper presents the composition of the organic matter (OM) on marine surface sediments from a degraded Tunisian coast analysed by pyrolysis and gas chromatography–mass spectrometry (GC-MS). High total OM contents (0.3–4.2%) were detected with high levels of saturated linear hydrocarbons. The aliphatic lipids had contributed with up to 11.7% of the total OM, and their distribution had consisted of resolved compounds (n-alkanes and fatty acid (FAs)) and an unresolved complex mixture. Hydrocarbons, primarily n-alkanes, were ranged from 368 to 3,886 μg g−1. The FAs (674–2,568 μg g−1) were dominated by derived primary production, and the short chain FAs (C16 and C18) were the most abundant throughout. The ubiquitous presence of petroleum contamination, mainly from offshore oil exploration, discharge of pollutants from rivers, shipping activities and atmospheric deposition was found in all samples. The Gabès littoral seems to be quite to very polluted near the industrial zone of Ghannouch. The C/H ratio (generally around 5.9), the thermal analysis and GC-MS of n-alkanes and FAs showed that the OM in the studied area was composed of anthropogenic/petrogenic, marine and continental sources. CONCLUSIONS: Our study represents an innovative approach to assessing environmental pollution. The evaluation of organic matter by examination of sterols, alkanes and fatty acids allows the identification of source, both anthropogenic and natural.
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