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1.
Chemosphere ; 242: 125169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675576

RESUMO

A systematic study on desorption of uranium in a natural soil has been carried out to reduce the level of uncertainty associated with the method employed to determine the values of the distribution coefficient (Kd). Generally, the operating method used to extract and analyze the soil solution determines the Kd values. Here, the centrifugation method has been used to obtain soil solution extracts. Several procedural parameters have been considered such as incubation time, the level of soil moisture relative to saturation (saturation degree) and centrifugation speed (equivalent to effective suction). In order to analyze the influence of soil structural characteristics, this study considers three grain-size fractions of soil: loamy coarse sand, loamy fine sand, and loam, all of which are obtained from a natural soil collected in a uranium mineralized area. Our results indicate that neither incubation time nor centrifugation speed influence the determination of Kd for uranium. The results also indicate that the level of soil moisture is the most important factor for determining 238U-Kd. It has been shown that the influence of moisture on Kd also depends on the structural characteristic of the soil. For the loamy coarse sand subsample, the moisture level during the incubation period showed a significant influence on the Kd. In addition, through the use of regression analysis, the pH was identified as the cofactor with the greatest influence on Kd of uranium.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Radioativos do Solo/análise , Solo/química , Urânio/análise , Concentração de Íons de Hidrogênio , Radioquímica , Água/análise
2.
Chemosphere ; 168: 832-838, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27825713

RESUMO

The soil-to-plant transfer factors were determined in a granitic area for the two long-lived uranium series radionuclides 238U and 226Ra. With the aim to identify a physical fraction of soil whose concentration correlates linearly with the plant concentration, the soil compartment was analyzed in various stages. An initial study identified the soil compartments as being either bulk soil or its labile fraction. The bulk soil was subsequently divided into three granulometric fractions consisting of: coarse sand, fine sand, and silt and clay. The soil-to-plant transfer of radionuclides for each of these three texture fractions was analyzed. Lastly, the labile fraction was extracted from each textural part, and the activity concentration of the radionuclides 238U and 226Ra was measured. In order to assess the influence of soil texture on the soil-to-plant transfer process, we sought to identify possible correlations between the activity concentration in the plant compartment and those found in the different fractions within each soil compartment. The results showed that the soil-to-plant transfer process for uranium and radium depends on soil grain size, where the results for uranium showed a linear relationship between the activity concentration of uranium in the plant and the fine soil fraction. In contrast, a linear relation between the activity concentration of radium in the plant and the soil coarse-sand fraction was observed. Additionally, the presence of phosphate and calcium in the soil of all of the compartments studied affected the soil-to-plant transfer of uranium and radium, respectively.


Assuntos
Plantas/metabolismo , Rádio (Elemento)/análise , Dióxido de Silício/química , Poluentes Radioativos do Solo/análise , Solo/química , Urânio/análise , Asteraceae/metabolismo , Fabaceae/metabolismo , Plantas/efeitos da radiação , Poaceae/metabolismo , Rádio (Elemento)/metabolismo , Poluentes Radioativos do Solo/efeitos adversos , Poluentes Radioativos do Solo/metabolismo , Urânio/metabolismo
3.
Chemosphere ; 95: 527-34, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24182407

RESUMO

Low-level alpha spectrometry techniques using semiconductor detectors (PIPS) and liquid scintillation (LKB Quantulus 1220™) were used to determine the activity concentration of (238)U, (234)U, (230)Th, (226)Ra, (232)Th, and (210)Pb in soil samples. The soils were collected from an old disused uranium mine located in southwest Spain. The soils were sampled from areas with different levels of influence from the installation and hence had different levels of contamination. The vertical profiles of the soils (down to 40 cm depth) were studied in order to evaluate the vertical distribution of the natural radionuclides. To determine the origin of these natural radionuclides the Enrichment Factor was used. Also, study of the activity ratios between radionuclides belonging to the same radioactive series allowed us to assess the different types of behaviors of the radionuclides involved. The vertical profiles for the radionuclide members of the (238)U series were different at each sampling point, depending on the level of influence of the installation. However, the profiles of each point were similar for the long-lived radionuclides of the (238)U series ((238)U, (234)U, (230)Th, and (226)Ra). Moreover, a major imbalance was observed between (210)Pb and (226)Ra in the surface layer, due to (222)Rn exhalation and the subsequent surface deposition of (210)Pb.


Assuntos
Monitoramento de Radiação , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Urânio/análise , Radioisótopos de Chumbo/análise , Rádio (Elemento)/análise , Solo/química , Espanha , Tório/análise
4.
J Hazard Mater ; 250-251: 439-46, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23500424

RESUMO

The effect of three chelating agents (citrate, EDTA, and EDDS) on the solubilization of radium from a granitic soil was studied systematically, considering different soil pH values, chelating agent concentrations, and leaching times. For all the chelating agents tested, the amount of radium leached proved to be strongly dependent on the pH of the substrate: only for acidic conditions did the amount of radium released increase significantly relative to the controls. Under the best conditions, the radium released from the amended soil was greater by factors of 20 in the case of citrate, 18 for EDTA, and 14 for EDDS. The greatest improvement in the release of radium was obtained for the citrate amendment at the highest concentration tested (50 mmol kg(-1)). A slightly lower amount of radium was leached with EDTA at 5 mmol kg(-1) soil, but the solubilization over time was very different from that observed with citrate or EDDS. With EDTA, a maximum in radium leaching was reached on the first day after amendment, while with citrate, the maximum was attained on the fourth day. With EDDS, radium leaching increased slightly but steadily with time (until the sixth day), but the net effect for the period tested was the lowest of the three reagents.


Assuntos
Quelantes/química , Ácido Edético/química , Etilenodiaminas/química , Succinatos/química , Ácido Cítrico/química , Concentração de Íons de Hidrogênio , Chumbo/análise , Rádio (Elemento)/análise , Solo/análise , Poluentes Radioativos do Solo/análise , Urânio/análise
5.
Appl Radiat Isot ; 70(4): 609-11, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22221465

RESUMO

In a previous paper the authors proposed a sequential method for the determination of isotopes of uranium, thorium, radium, and lead from environmental samples using alpha-particle spectrometry and LSC techniques. Although the radiochemical yields were suitable when the assays were performed on synthetic samples, application to real environmental samples caused a major decrease in the radiochemical yield, especially for uranium in inorganic samples (soils). A modification of the procedure is described that overcomes this drawback.


Assuntos
Partículas alfa , Poluentes Ambientais/análise , Radioisótopos/análise , Análise Espectral/métodos , Radioisótopos de Chumbo , Poluentes Radioativos/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo , Urânio/análise
6.
J Hazard Mater ; 198: 224-31, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-22047721

RESUMO

A systematic study was made of the effects of three soil amendments on the solubilization of uranium from a granitic soil. The aim was to optimize solubilization so as to enhance bioavailability for the purposes of remediation. The three amendments tested were with citrate, EDTA, and EDDS as chelating agents. The effects of pH, chelator concentration, and leaching time were studied. The most important factor in uranium solubilization was found to be the pH. In the absence of chelating agents, the greatest solubilization was obtained for alkaline conditions, with values representing about 15% of the total uranium activity in the bulk soil. There were major differences in uranium solubilization between the different amendments. The citrate treatment was the most efficient at acidic pH, particularly with the greatest concentration of citrate tested (50 mmol kg(-1)) after 6 days of treatment. Under these conditions, the uranium concentration in solution was greater by a factor of 356 than in the control suspension, and represented some 63% of the uranium concentration in the bulk soil. Under alkaline conditions, the EDTA and EDDS treatments gave the greatest uranium activity concentrations in solution, but these concentrations were much lower than those with the citrate amendment, and were not very different from the control results. The uranium extraction yield with EDDS amendment was greater than with EDTA.


Assuntos
Quelantes/química , Ácido Cítrico/química , Ácido Edético/química , Etilenodiaminas/química , Poluentes do Solo/química , Succinatos/química , Urânio/química , Concentração de Íons de Hidrogênio , Solubilidade
7.
Appl Radiat Isot ; 68(6): 1154-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20153657

RESUMO

The soil-to-plant transfer factors of natural uranium isotopes ((238)U and (234)U), (230)Th, (226)Ra, and (210)Pb were studied in a disused uranium mine located in the Extremadura region in the south-west of Spain. The plant samples included trees (Quercus ilex, Quercus suber, and Eucalyptus cameldulensis) and one shrub (Cytisus multiflorus). All of them are characteristic of Mediterranean environments. The activity concentrations in leaves and fruit were determined for the tree species at different stages of growth. For the shrub, the total above-ground fraction was considered in three seasons. For old leaves and fruit, the highest activity concentrations were found in Eucalyptus cameldulensis for all the radionuclides studied, except in the case of (230)Th that presented similar activity concentrations in all of the tree species studied. In every case, the transfer to fruit was less than the transfer to leaves. In the shrub, the results depended on the season of sampling, with the highest value obtained in spring and the lowest in autumn. Important correlations were obtained for (238)U and (226)Ra between the activity ratio in soils with that in leaves or fruit.


Assuntos
Rádio (Elemento)/metabolismo , Poluentes Radioativos do Solo/metabolismo , Tório/metabolismo , Árvores/metabolismo , Urânio/metabolismo , Eucalyptus/metabolismo , Fabaceae/metabolismo , Frutas/metabolismo , Radioisótopos de Chumbo/metabolismo , Folhas de Planta/metabolismo , Quercus/metabolismo , Solo , Espanha
8.
Chemosphere ; 74(2): 293-300, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18848715

RESUMO

Seedlings of Helianthus annuus L. (HA) and Brassica juncea (BJ) were used to test the effect of the pH, the presence of phosphates, and the addition of ethylene-diamine-tetraacetic acid (EDTA) or citrate on the uptake and the translocation of uranium isotopes ((238)U, (235)U, and (234)U) and (226)Ra. The results indicated that the presence of phosphates generally reduces the uptake and transfer of uranium from the roots to the shoots of HA. In the case of BJ, while phosphate enhanced the retention of uranium by roots, the translocation was poorer. Likewise, for (226)Ra, the best translocation was in the absence of phosphates for both species. The addition of citrate increased the translocation of uranium for both species, but had no clear effect on the transfer of (226)Ra. The effect of EDTA was much more moderate both for uranium and for (226)Ra, and for both plant species. Only noticeable was a slightly better uptake of (226)Ra by BJ at neutral pH, although the translocation was lower.


Assuntos
Helianthus/metabolismo , Mostardeira/metabolismo , Rádio (Elemento)/metabolismo , Urânio/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Fosfatos/química , Fosfatos/farmacologia , Raízes de Plantas/metabolismo , Poluentes Radioativos/metabolismo
9.
J Environ Radioact ; 99(8): 1247-54, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18433950

RESUMO

The influence of soil texture on the distribution and availability of (238)U, (230)Th, and (226)Ra in soils was studied in soil samples collected at a rehabilitated uranium mine located in the Extremadura region in south-west Spain. The activity concentration (Bqkg(-1)) in the soils ranged from 60 to 750 for (238)U, from 60 to 260 for (230)Th, and from 70 to 330 for (226)Ra. The radionuclide distribution was determined in three soil fractions: coarse sand (0.5-2mm), medium-fine sand (0.067-0.5mm), and silt and clay (<0.067 mm). The relative mobility of the natural radionuclides in the different fractions was studied by comparison of the activity ratios between radionuclides belonging to the same radioactive series. The lability of these radionuclides in each fraction was also studied through selective extraction from the soils using a one-step sequential extraction scheme. Significant correlations were found for (238)U, (230)Th, and (226)Ra between the activity concentration per fraction and the total activity concentration in the bulk soil. Thus, from the determination of the activity concentration in the bulk soil, one could estimate the activity concentration in each fraction. Correlations were also found for (238)U and (226)Ra between the labile activity concentration in each fraction and the total activity concentration in bulk soil. Assuming that there is some particle-size fraction that predominates in the process of soil-to-plant transfer, the parameters obtained in this study should be used as correction factors for the transfer factors determined from the bulk soil in previous studies.


Assuntos
Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Solo , Tório/análise , Urânio/análise
10.
Sci Total Environ ; 393(2-3): 351-7, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18272206

RESUMO

The elimination of natural uranium and (226)Ra from contaminated waters by rhizofiltration was tested using Helianthus annuus L. (sunflower) seedlings growing in a hydroponic medium. Different experiments were designed to determine the optimum age of the seedlings for the remediation process, and also to study the principal way in which the radionuclides are removed from the solution by the sunflower roots. In every trial a precipitate appeared which contained a major fraction of the natural uranium and (226)Ra. The results indicated that the seedlings themselves induced the formation of this precipitate. When four-week-old seedlings were exposed to contaminated water, a period of only 2 days was sufficient to remove the natural uranium and (226)Ra from the solution: about 50% of the natural uranium and 70% of the (226)Ra were fixed in the roots, and essentially the rest was found in the precipitate, with only very small percentages fixed in the shoots and left in solution.


Assuntos
Helianthus/metabolismo , Rádio (Elemento)/metabolismo , Urânio/metabolismo , Poluentes Radioativos da Água/metabolismo , Precipitação Química , Filtração , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Rádio (Elemento)/química , Plântula/metabolismo , Urânio/química , Poluentes Radioativos da Água/química , Purificação da Água/métodos
11.
Phytomedicine ; 14(2-3): 147-52, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16860978

RESUMO

Isolation and biological characterization of pure compounds was used to identify and characterize estrogenic activity and estrogen receptors (ER) preference in chemical components of Achillea millefolium. This medicinal plant is used in folk medicine as an emmenagogue. In vitro assay, based on recombinant MCF-7 cells, showed estrogenic activity in a crude extract of the aerial parts of A. millefolium. After fractionation of the crude extract with increasing polar solvents, estrogenic activity was found in the methanol/water fraction. Nine compounds were isolated and characterized by HR-MS spectra and 1D- and 2D-NMR techniques. In particular, dihydrodehydrodiconiferyl alcohol 9-O-beta-D-glucopyranoside - a glycosyl-neolignan - was isolated for the first time from the genus Achillea in addition to six flavone derivatives, apigenin, apigenin-7-O-beta-D-glucopyranoside, luteolin, luteolin-7-O-beta-D-glucopyranoside, luteolin-4'-O-beta-D-glucopyranoside, rutin, and two caffeic acid derivatives, 3,5-dicaffeoylquinic acid and chlorogenic acid. Apigenin and luteolin, the most important estrogenic compounds among those tested, were studied for their ability to activate alpha or beta estrogen receptors (ERalpha, ERbeta) using transiently transfected cells. Our results suggest that isolation and biological characterization of estrogenic compounds in traditionally used medicinal plants could be a first step in better assessing further (e.g. in vivo) tests of nutraceutical and pharmacological strategies based on phytoestrogens.


Assuntos
Achillea , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/efeitos dos fármacos , Fitoestrógenos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Células Cultivadas/efeitos dos fármacos , Feminino , Humanos , Técnicas In Vitro , Fitoestrógenos/administração & dosagem , Fitoestrógenos/química , Fitoestrógenos/uso terapêutico , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico
12.
Phytother Res ; 20(7): 576-80, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16619333

RESUMO

A selection of wild plants collected in Valsesia (Northwest Italy) was screened for their in vitro antioxidant activity. Aerial parts of selected plants were dried at room temperature and powdered. Then, four sequential extractions were performed with increasing polarity solvents, i.e. n-hexane, chloroform, chloroform-methanol (9:1, v/v) and methanol. By employing different assays, it was shown that all the methanol extracts of the samples collected were endowed with antioxidant activity, though, as expected, their potency varied according to the different tests. In particular, plants of the Thymus and Achillea genus displayed the highest activity. Given that a diet rich in wild plants is associated with a reduced incidence of degenerative diseases, such as atherosclerosis and cancer, this study suggests that some Valsesia plants could be pharmaceutically exploited.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Plantas/química , Achillea/química , Artemisia/química , Cardamine/química , Gentiana/química , Itália , Extratos Vegetais/química , Timo/química , Valeriana/química
13.
Sci Total Environ ; 361(1-3): 1-7, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16182341

RESUMO

The linearity assumption of the validation of soil-to-plant transfer factors of natural uranium and (226)Ra was tested using Helianthus annuus L. (sunflower) grown in a hydroponic medium. Transfer of natural uranium and (226)Ra was tested in both the aerial fraction of plants and in the overall seedlings (roots and shoots). The results show that the linearity assumption can be considered valid in the hydroponic growth of sunflowers for the radionuclides studied. The ability of sunflowers to translocate uranium and (226)Ra was also investigated, as well as the feasibility of using sunflower plants to remove uranium and radium from contaminated water, and by extension, their potential for phytoextraction. In this sense, the removal percentages obtained for natural uranium and (226)Ra were 24% and 42%, respectively. Practically all the uranium is accumulated in the roots. However, 86% of the (226)Ra activity concentration in roots was translocated to the aerial part.


Assuntos
Helianthus/metabolismo , Rádio (Elemento)/análise , Urânio/análise , Biodegradação Ambiental , Helianthus/crescimento & desenvolvimento , Hidroponia , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/química , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Rádio (Elemento)/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Solo , Urânio/metabolismo , Purificação da Água/métodos
14.
Arch. med. deporte ; 22(107): 243-246, mayo-jun. 2005. ilus
Artigo em Es | IBECS | ID: ibc-040504

RESUMO

Se presenta un caso de herniación cervical múltiple en un paciente previamente sano tras una manipulación cervical quiropráctica. Se realiza una revisión de la literatura sobre las complicaciones surgidas tras manipulaciones vertebrales. Se pretende llamar la atención sobre los peligros de estas técnicas de manipulación raquídea, ampliamente extendidas, en muchas ocasiones realizadas por personal sin titulación sanitaria con un insuficiente estudio médico previo sobre la causa del dolor del paciente


We present a case of multiple cervical spine disc herniation in a previously healthy patient following chiropractic manipulation. The aim of this paper is to review the medical literature about the complications following spinal manipulation to emphasize the potential risks of this widely extended therapeutic procedure, performed in many cases by non-qualified personnel without medical training


Assuntos
Humanos , Cervicalgia/terapia , Manipulação Quiroprática/efeitos adversos , Deslocamento do Disco Intervertebral/etiologia , Cervicalgia/etiologia , Deslocamento do Disco Intervertebral/diagnóstico
15.
J Environ Radioact ; 79(3): 315-30, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15607518

RESUMO

A new version of a classical method was applied to study the distribution of natural radionuclides (238U, 230Th, and 226Ra) in the soil fractions obtained by a sequential extraction procedure. The potential significance of the fractions obtained with this method was tested on two very similar soils but with very different contents of the three radionuclides, collected in the proximity of a disused uranium mine located in the Extremadura region in the south-west of Spain. The results confirmed that, if only non-residual fractions are considered, the sequential method applied shows a characteristic speciation pattern of these natural radionuclides in this soil matrix, i.e., the distribution of each of the three radionuclides was very similar for the two soil samples.


Assuntos
Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise , Monitoramento Ambiental , Rádio (Elemento)/química , Espanha , Tório/química , Urânio/química
16.
Rev Med Univ Navarra ; 48(3): 39-41, 2004.
Artigo em Espanhol | MEDLINE | ID: mdl-15622923

RESUMO

We present a case of multiple cervical spine disc herniation in a previously healthy patient following chiropractic manipulation. The aim of this paper is to review the medical literature about the complications following spinal manipulation to emphasize the potential risks of this widely extended therapeutic procedure, performed in many cases by non-qualified personnel without medical training.


Assuntos
Vértebras Cervicais , Deslocamento do Disco Intervertebral/etiologia , Manipulação Quiroprática/efeitos adversos , Adulto , Humanos , Masculino
17.
Phytother Res ; 18(6): 468-70, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15287071

RESUMO

The essential oil, various extracts at different polarity, fractions, and pure compounds obtained from Nigella damascena plants and seeds were screened for biological activity. Antimicrobial tests showed the essential oil to be active only against Gram positive bacteria; among the extracts, the BuOH was active against Pseudomonas aeruginosa and Staphylococcus aureus. Molluscicidal activity was absent.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Moluscocidas/farmacologia , Nigella damascena , Fitoterapia , Óleos de Plantas/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Moluscocidas/administração & dosagem , Moluscocidas/uso terapêutico , Óleos de Plantas/administração & dosagem , Óleos de Plantas/uso terapêutico , Caramujos/efeitos dos fármacos
18.
Appl Radiat Isot ; 61(2-3): 345-50, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15177369

RESUMO

Two sequential extraction procedures, Tessier's method (Anal. Chem. 51(7) (1979) 844), and a current version known as Schultz's method (J. Environ. Radioact. 40(2) (1998) 155), were compared. The two procedures were applied to a natural soil sample that presents high activity concentrations in natural radionuclides of the 238U series. Reproducibility studies of each method and a comparison between the two sets of results were performed for uranium, thorium, and radium. The results were different for each radionuclide. Analysis of the extracted fractions was carried out by alpha spectrometry.


Assuntos
Fracionamento Químico/métodos , Poluentes Radioativos do Solo/análise , Análise Espectral/métodos , Urânio/análise , Partículas alfa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Urânio/classificação
19.
Fitoterapia ; 74(4): 420-2, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12781820

RESUMO

The isolation of five flavonol glycosides (1-5) from the flowers of Aconitum vulparia is reported, together with the 1H- and 13C-NMR spectral data in CD(3)OD of compound 3 and 5.


Assuntos
Aconitum , Flavonoides/química , Glicosídeos/química , Fitoterapia , Extratos Vegetais/química , Flores , Humanos
20.
J Environ Radioact ; 65(2): 161-75, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12527233

RESUMO

The transfer factors (TF) for natural uranium isotopes (238U and 234U), thorium isotopes (232Th, 230Th and 228Th), and 226Ra were obtained in plant samples (grass-pasture) growing in granitic and alluvial soils around a disused uranium mine located in the Extremadura region in the south-west of Spain. Affected and non-affected areas of the mine presented large differences in the activity concentrations of radionuclides of the uranium series. We also determined transfer factors for several stable elements (essential and non-essential). A set of statistical tests were applied to validate the data. The results showed that the transfer factors for both the natural radionuclides and the stable elements are independent of the two substrate types involved and also of the two areas considered in the study.


Assuntos
Radônio/farmacocinética , Poluentes Radioativos do Solo/farmacocinética , Tório/farmacocinética , Urânio/farmacocinética , Monitoramento Ambiental , Região do Mediterrâneo , Mineração , Poaceae/química , Radônio/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise
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