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1.
Environ Sci Pollut Res Int ; 23(14): 14087-101, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27044293

RESUMEN

Rare earth elements (REEs) are typically conservative elements that are scarcely derived from anthropogenic sources. The mobilization of REEs in the environment requires the monitoring of these elements in environmental matrices, in which they are present at trace level. The determination of 11 REEs in carpet-forming moss species (Hypnum cupressiforme) collected from 44 sampling sites over the whole territory of the country were done by using epithermal neutron activation analysis (ENAA) at IBR-2 fast pulsed reactor in Dubna. This paper is focused on REEs (lanthanides) and Sc. Fe as typical consistent element and Th that appeared good correlations between the elements of lanthanides are included in this paper. Th, Sc, and REEs were never previously determined in the air deposition of Albania. Descriptive statistics were used for data treatment using MINITAB 17 software package. The median values of the elements under investigation were compared with those of the neighboring countries such as Bulgaria, Macedonia, Romania, and Serbia, as well as Norway which is selected as a clean area. Geographical distribution maps of the elements over the sampled territory were constructed using geographic information system (GIS) technology. Geochemical behavior of REEs in moss samples has been studied by using the ternary diagram of Sc-La-Th, Spider diagrams and multivariate analysis. It was revealed that the accumulation of REEs in current mosses is associated with the wind-blowing metal-enriched soils that is pointed out as the main emitting factor of the elements under investigation.


Asunto(s)
Briófitas/química , Monitoreo del Ambiente/métodos , Metales de Tierras Raras/análisis , Contaminantes Atmosféricos/análisis , Albania , Bryopsida , Sistemas de Información Geográfica , Análisis Multivariante , Análisis de Activación de Neutrones
2.
J Environ Radioact ; 117: 9-12, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22664381

RESUMEN

The results of the low-background gamma-spectrometric measurements of sediments from three Western Carpathian mountain rivers during a three year term (2006-2009) are presented. These sediments are dynamic and very informative for environmental monitoring of a large watershed. Distances between the river sample points were 10-20 km and the total change of the altitude was 200-400 m. The proposed sampling scheme allows to investigate the changes of seasonal and spatial distributions of the radionuclides in sediment. The statistical correlations between the sampling points, the water level of the river and the contents of natural or anthropogenic radionuclides in sediment were studied. The effect of the intensive leaching of radionuclides from sediments during the flood season is shown and this can be considered as the principal self-purification mechanism.


Asunto(s)
Sedimentos Geológicos/análisis , Radioisótopos/análisis , Monitoreo del Ambiente , Ríos
3.
J Environ Radioact ; 117: 19-24, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22326019

RESUMEN

In the present work, moss samples collected in Slovakia and Belarus were assayed with respect to gamma-emitting radionuclides. The results for (137)Cs and (210)Pb are discussed. Moss was used for the first time in Belarus, as a biological indicator of radioactive environmental pollution in consequence of the Chernobyl accident in 1986. In Belarus, the maximum activity of (137)Cs was observed in the Gomel region near Mazyr (6830 Bq/kg) and the minimum activity in the Vitebsyevsk Region near Luzhki-Yazno (5 Bq/kg). "Hot spots" were also observed near the towns Borisow and Yuratsishki. The results of measurements of (137)Cs in moss samples collected in 2000, 2006 and 2009 in the same localities of Slovakia are presented and compared with the results of air monitoring of (137)Cs carried out in Slovakia from 1977 until 2010. Measurements of the (210)Pb concentration in moss samples collected over the territory of Slovakia showed, that the median value exceed 2.3 times median value of (210)Pb obtained for Belarus moss. For that reason, the inhalation dose for man from (210)Pb and (137)Cs in Slovakia is more than twice as high as in Belarus, in spite of the initially very high (137)Cs exposure in the latter country.


Asunto(s)
Briófitas/metabolismo , Radioisótopos de Cesio/metabolismo , Radioisótopos de Plomo/metabolismo , Monitoreo de Radiación/métodos , República de Belarús , Eslovaquia
4.
Environ Monit Assess ; 185(1): 955-68, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22488660

RESUMEN

The well-known moss bags technique was applied in the heavily polluted Thriasion Plain region, Attica, Greece, in order to study the spatiotemporal distribution, in the atmosphere, of the following 32 elements: Na, Al, Cl, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni, Co, Zn, As, Se, Br, Sr, Mo, Sb, I, Ba, La, Ce, Sm, Tb, Dy, Yb, Hf, Ta, Hg, Th, and U. The moss bags were constituted of Sphagnum girgensohnii materials. The bags were exposed to ambient air in a network of 12 monitoring stations scattered throughout the monitoring area. In order to explore the temporal variation of the pollutants, four sets of moss bags were exposed for 3, 6, 9, and 12 months. Instrumental neutral activation analysis was used for the determinations of the elements. The data were analyzed using the Pearson correlations, the partial redundancy analysis, and the biplot statistical methods. Some pairs of elements were highly correlated indicating a probable common source of origin. The levels of the measured pollutants were unevenly distributed throughout the area and different pollutants exhibited different spatial patterns. In general, higher loads were observed in the stations close to and within the industrial zone. Most of the measured elements (e.g., Al, Ca, Ni, I, Zn, Cr, and As) exhibited a monotonic accumulation trend over time. Some elements exhibited different dynamics. The elements Mn, Mo, and Hg showed a decreasing trend, probably due to leaching and/or volatilization processes over time. Na and Br initially showed an increasing trend during the winter and early spring periods but decreased drastically during the late warm period. The results further suggest that the moss bags technique would be considered valuable for the majority of elements but should be used with caution in the cases of elements vulnerable to leaching and/or volatilization. It also suggests that the timing and the duration of the exposure of moss materials should be considered in the interpretation of the results.


Asunto(s)
Contaminantes Atmosféricos/análisis , Briófitas/química , Monitoreo del Ambiente/métodos , Contaminación del Aire/estadística & datos numéricos , Grecia , Estaciones del Año , Análisis Espacio-Temporal
5.
J Environ Radioact ; 117: 45-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21880403

RESUMEN

Terrestrial mosses are a promising medium for investigation and monitoring of airborne radionuclide depositions due to their widespread occurrence, ease of sampling, and the possibility of high-resolution gamma spectrometry measurements without preparatory chemical treatment of samples. The overall objective of the present study was to compare (7)Be, (210)Pb and (137)Cs activity concentrations (in Bq/kg) in moss samples collected at two different climate zones: the south of Thailand (7 °N) and in Serbia (∼45 °N) in order to examine deposition of airborne radionuclide in these distant areas. Significant difference of the (210)Pb content (almost a factor of 2) in mosses was observed. The mean value of (7)Be activity in samples from Serbia was almost 40% higher than activity of those collected in Thailand. Level of (137)Cs in Thailand mosses was below the detection limit. It was shown that air transport of water droplets in the area of waterfalls and strong turbulence can deposit U and Th daughter nuclei.


Asunto(s)
Briófitas/química , Monitoreo de Radiación/métodos , Radioisótopos/análisis , Serbia , Tailandia
6.
J Hazard Mater ; 171(1-3): 182-8, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19541410

RESUMEN

To clarify the peculiarities of trace element accumulation in moss bags technique (active biomonitoring), samples of the moss Sphagnum girgensohnii Rusow were exposed in bags with and without irrigation for 15 days up to 5 months consequently in the semi-urban area of Belgrade (Serbia) starting from July 2007. The accumulation capacity for 49 elements determined by ICP-MS in wet and dry moss bags was compared. The concentration of some elements, i.e. Al, V, Cr, Fe, Zn, As, Se, Sr, Pb, and Sm increased continuously with exposure time in both dry and wet moss bags, whereas concentration of Na, Cl, K, Mn, Rb, Cs, and Ta decreased. Irrigation of moss resulted in a higher accumulation capacity for most of the elements, especially for Cr, Zn, As, Se, Br, and Sr. Principal component analysis was performed on the datasets of element concentrations in wet and dry moss bags for source identification. Results of the factor analysis were similar but not identical in the two cases due to possible differences in element accumulation mechanisms.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Sphagnopsida/química , Oligoelementos/análisis , Atmósfera , Exposición a Riesgos Ambientales/análisis , Espectrometría de Masas/métodos , Análisis de Componente Principal , Estaciones del Año , Serbia , Factores de Tiempo , Salud Urbana/estadística & datos numéricos
7.
Appl Radiat Isot ; 67(5): 939-43, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19230682

RESUMEN

The content of seven major (Na, Al, Cl, Mn, K, Ca, Ti, Fe) and 30 trace (Sc, V, Cr, Ni, Co, Zn, Cu, As, Sr, Rb, Zr, Mo, Sn, In, Sb, Ba, Cs, La, Ce, Nd, Eu, Sm, Tb, Dy, Yb, Hf, Ta, W, Th, U) elements determined by INAA in 13 samples of abyssal clay and two samples of micronodules collected from the North pacific Ocean Clarion-Clipperton abyssal plane is presented and discussed with respect to some rocks models.


Asunto(s)
Silicatos de Aluminio/química , Metales/análisis , Análisis de Activación de Neutrones , Oligoelementos/análisis , Arcilla , Sedimentos Geológicos/química , Océanos y Mares
8.
Appl Radiat Isot ; 67(5): 901-6, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19231213

RESUMEN

Six major (Na, Al, K, Ca, Ti, Fe) and 28 trace (Sc, Cr, V, Mn, Co, Zn, Cu, As, Br, Sr, Rb, Zr, Mo, Sn, Sb, Ba, Cs, La, Ce, Nd, Eu, Sm, Tb, Hf, Ta, W, Th and U) elements were determined by epithermal neutron activation analysis (ENAA) in nine Meridional Carpathian and Macin Mountains samples of igneous and metamorphic rocks. Correlation and principal factor analysis were used to interpret data while natural radionuclides radiometry shows a good correlation with ENAA results.


Asunto(s)
Sedimentos Geológicos/análisis , Metales/análisis , Oligoelementos/análisis , Análisis de Componente Principal , Radioisótopos/análisis , Radiometría , Rumanía
9.
Environ Pollut ; 157(2): 673-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18814945

RESUMEN

Active biomonitoring with wet and dry moss bags was used to examine trace element atmospheric deposition in the urban area of Belgrade. The element accumulation capability of Sphagnum girgensohnii Russow was tested in relation to atmospheric bulk deposition. Moss bags were mounted for five 3-month periods (July 2005-October 2006) at three representative urban sites. For the same period monthly bulk atmospheric deposition samples were collected. The concentrations of Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb were determined by instrumental neutron activation analyses and atomic absorption spectrometry. Significant accumulation of most elements occurred in the exposed moss bags compared with the initial moss content. High correlations between the elements in moss and bulk deposits were found for V, Cu, As, and Ni. The enrichment factors of the elements for both types of monitor followed the same pattern at the corresponding sites.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Sphagnopsida/química , Oligoelementos/análisis , Exposición a Riesgos Ambientales/análisis , Estaciones del Año , Serbia , Salud Urbana/estadística & datos numéricos
10.
Environ Monit Assess ; 138(1-3): 107-18, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17665145

RESUMEN

For the first time the atmospheric deposition of trace metals was studied over the entire territory of the Republic of Macedonia. Samples of the terrestrial mosses Hypnum cupressiforme, Camptothecium lutescens, and Homalothecium sericeum were collected in September-October 2002 at 73 sites evenly distributed over the country, and a total of 43 elements were determined by instrumental neutron activation analysis and atomic absorption spectrometry. Principal component factor analysis was used to identify the most polluted areas and characterize different pollution sources. The most important sources of trace metal deposition are ferrous and non-ferrous smelters, oil refineries, fertilizer production plants, and central heating stations. Four areas appear to be particularly exposed to metal pollution: Veles, Skopje, Tetovo, and Kavadarci-Negotino, whereas the predominantly agricultural regions in the south, southwest, and southeast show levels closer to European median values for most elements of mainly pollution origin.


Asunto(s)
Bryopsida/metabolismo , Elementos Químicos , Metales/metabolismo , Monitoreo del Ambiente , República de Macedonia del Norte
11.
Environ Monit Assess ; 108(1-3): 229-40, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16160789

RESUMEN

Active moss biomonitoring using the species Sphagnum girgensohnii was tested at a strongly polluted site in Romania (Baia Mare) according to a novel sampling design. Nine moss transplants from each of the two background areas (Dubna, Russia and Vitosha Mountain, Bulgaria) were deployed in parallel on balconies about 24 m above street level for 4 months. The samples were analyzed for 36 elements using instrumental neutron activation analysis (INAA). Based on the results obtained the sampling variability is discussed in relation to the analytical variability, and the relative uptake of the different elements is assessed. The moss-bags using Sphagnum girgensohnii demonstrate a high or a very high relative uptake for a majority of the 36 investigated elements, but the values depend on the initial element concentration in the moss. Moss leaves analyzed separately showed somewhat higher levels than stems for many elements. Practical considerations however still speak in favor of using the whole moss for transplants.


Asunto(s)
Contaminantes Atmosféricos/análisis , Elementos Químicos , Monitoreo del Ambiente/métodos , Sphagnopsida/química , Industrias , Análisis de Activación de Neutrones , Hojas de la Planta/química , Tallos de la Planta/química , Rumanía
13.
J Environ Sci Health B ; 38(2): 181-92, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12617556

RESUMEN

This article presents basic data on the content of Cr, Fe, Ni, Cu, Zn, As, Cd, Sb, Hg, and Pb in staple foodstuffs and agriproduct grown in Russia (Astrakhan region and the town of Belovo) and Egypt (Helwan region). The dependence of the concentration of metals in agriproducts on the content and chemical form of existence in irrigation water and soils is indicated.


Asunto(s)
Productos Agrícolas/química , Contaminación de Alimentos/análisis , Metales Pesados/análisis , Seguridad de Productos para el Consumidor , Egipto , Análisis de los Alimentos , Análisis de Activación de Neutrones , Federación de Rusia , Contaminantes del Suelo/análisis , Espectrofotometría Atómica , Contaminantes Químicos del Agua/análisis
14.
J Pharm Biomed Anal ; 30(1): 87-97, 2002 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-12151068

RESUMEN

The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. The background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in S. platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loading of the above elements was characterized. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed.


Asunto(s)
Proteínas Bacterianas/análisis , Cianobacterias/química , Yodo/química , Selenio/química , Biomasa , Calibración , Cianobacterias/crecimiento & desarrollo , Metales Pesados/análisis , Análisis de Activación de Neutrones , Control de Calidad , Spirulina , Comprimidos , Oligoelementos/análisis
15.
Biol Trace Elem Res ; 43-45: 315-22, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7710842

RESUMEN

Concentration of 13 elements in bone tissue of mice held in tightly spaced cages for 3 wk, which caused an acute stress reaction, was determined by means of neutron activation analysis. Functionally different bone tissues of mice skeletons--the femur, accomplishing both supporting and dynamic functions; the parietal bone, being practically immovable; and the ectopic bone, newly formed under kidney capsule in the place of syngeneic bone marrow implantation--were analyzed. Similar dynamics of the elemental composition of investigated bones was found: the progressive demineralization owing to the loss of Ca, P, Mg, and Fe is accompanied by the compensatory inclusion of Sr in the bone tissues. In the ectopic bone, it was not as high. During evolution under hypokinetic stress, the microelement concentrations (Zn, Cr, Rb, Ru, Br, Co, Sb) change significantly. Results obtained form the evidence for some system character of osteoporosis at limited mobility.


Asunto(s)
Desmineralización Ósea Patológica/metabolismo , Desarrollo Óseo/fisiología , Huesos/metabolismo , Hipocinesia/metabolismo , Estrés Psicológico/metabolismo , Animales , Desmineralización Ósea Patológica/psicología , Médula Ósea/química , Trasplante de Médula Ósea/fisiología , Huesos/química , Semivida , Hidroxiapatitas/metabolismo , Cinética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Movimiento/fisiología , Análisis de Activación de Neutrones
17.
Sci Total Environ ; 95: 141-8, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2169646

RESUMEN

This paper considers some features of the production of phosphorus fertilizers in relation to pollution of the environment by rare-earth elements by measuring the change in the rare-earth elements interrelationship in snow. The main source of the pollution is identified. The distribution of pollutants is dependent on the size of the associated aerosol particles. We also report data on the concentrations of the pollutants in agricultural plants, employees' hair and hair of local residents.


Asunto(s)
Contaminación Ambiental , Fertilizantes , Cabello/análisis , Oligoelementos/análisis , Agricultura , Humanos , Fósforo , Plantas/análisis , Población Rural
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