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1.
J Environ Radioact ; 229-230: 106548, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33581482

RESUMO

The 239+240Pu and 137Cs activities and 240Pu/239Pu atom ratios in surface soil and soil core collected from Qinghai-Tibet Plateau were investigated. The maximum of 239+240Pu and 137Cs activity concentrations in five soil cores were found in upper layers and have a same trend: the maximum followed by exponential decline. The 240Pu/239Pu atom ratio ranged from 0.160 ± 0.009 to 0.212 ± 0.012, clarified that the plutonium mainly came from the global fallout and the contribution of Lop Nor test sites was negligible. In addition, the vertical profiles of radionuclides (210Pb, 238U, 232Th, 226Ra, 40K) have been studied and a high correlation has been found between them. The correlations of Pu between organic matter (OM) and heavy metals were also studied. Person Correlation Coefficients revealed Pu had significant positive correlations with organic matter and Cd, Cu, Co, Zn, but negative correlation with Tl. The results have important implication for further understanding of the sources, records and environmental impacts of global and regional nuclear activities, which expanded the database of Pu activity level and atom ratio in Chinese soil and established a foundation for future environmental risk assessment.


Assuntos
Plutônio , Monitoramento de Radiação , Poluentes Radioativos do Solo , Florestas , Humanos , Plutônio/análise , Solo , Poluentes Radioativos do Solo/análise , Tibet
2.
Environ Monit Assess ; 193(2): 55, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33427968

RESUMO

The importance of the soil degradation in the Mediterranean area, more particularly in Algeria, has revealed the need for a diagnosis of the erosion processes' dynamism. In this context, the present work discusses the results obtained by different approaches (conventional methods, Revised Universal Soil Loss Equation (RUSLE), and fallout radionuclides (use of FRNs)). The use of nuclear techniques (FRNs) such as Cesium-137, Lead-210, and Beryllium-7 as tracers can provide an invaluable amount of information on rates of soil loss that is associated with sheet and rill erosion as well as on the redistribution and transfer of that sediment within the landscape. This work mainly presents the results obtained by the application of nuclear isotopes. In the Fergoug watershed study, the use of conventional and nuclear methods has led to converging results. The latter can be summarized as follows: sheet erosion from 1.5 to 10 t·ha-1·year-1 for bare soil and 0.1 to 4 t·ha-1·year-1 for cultivated soil. The use of the RUSLE method has shown that erosion is medium to very high (1 to 33 t·ha-1·year-1). Estimates of erosion by Cesium-137 (137Cs) provided a good understanding of the distribution of the isotope at the slope level and therefore of erosion. The erosion rate is from 26 to 42 t·ha-1·year-1, depending on the models used. On the other hand, sedimentation reached 35 and 55 t·ha-1·year-1 downstream of the slopes. The variation of 137Cs between transects and along the same transect is linked to erosion. The 137Cs method has provided a great deal of information and thus constitutes, by its accuracy and speed, an effective and valuable tool for assessing erosion for medium term (50 years) and monitoring the impacts of land use. It can enable one to overcome the various constraints and limits encountered in the various conventional approaches. It thus appears to be an essential alternative or an effective tool to supplement the conventional methods.


Assuntos
Monitoramento Ambiental , Poluentes Radioativos do Solo , Argélia , Radioisótopos de Césio/análise , Conservação dos Recursos Naturais , Solo , Poluentes Radioativos do Solo/análise
3.
J Environ Radioact ; 229-230: 106530, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33482539

RESUMO

The Acacia auriculiformis is a tree common in tropical Asian countries, capable of growing in many different soil types, so it could be used for biomonitoring for high natural radionuclide areas in tropical and subtropical climates. The transfer factor (TF) of radionuclides from soil to A. auriculiformis in eight uranium and rare earth element (REE) mining areas of North Vietnam was investigated. The activity concentrations 226Ra, 238U, 137Cs, 228Ra, and 40K in both soil and A. auriculiformis showed considerable variation. The TFs of these radionuclides also varied in a wide range. In most of the eight areas, the highest TF was observed for 137Cs and 228Ra. While the TFs for 226Ra and 238U were smallest. In addition, the TFs for radionuclides near REE mines were similar to those observed near uranium mines. The TFs for A. auriculiformis were within the ranges of TF reported for other plants, except for 137Cs.


Assuntos
Acacia , Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Solo , Poluentes Radioativos do Solo/análise , Árvores , Urânio/análise , Vietnã
4.
J Environ Radioact ; 229-230: 106538, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33485191

RESUMO

Transfer factors of radium 226(226Ra), lead 210(210Pb), polonium 210 (210Po), uranium 238 (238U) and thorium 234(234Th) from five different agricultural soils in Syria to coriander, parsley and mint were investigated in a pot culture experiment. Geometric means of transfer factors (TF)were226Ra (0.13),210Pb(0.03), 210Po (0.02) and 238U (1.76) were within worldwide values, while TF values for 234Th (1.35) were higher than those recorded globally. The available transfer factor (ATF) values ranged between 0.03 and 1.45, 0.33 and 3.2, 0.10 and 3.36, 1.30 and 16.2 and 1.0 and 6.95 for226Ra,210Pb,210Po, 238U and 234Th, respectively. However, it is worth mentioning that the data from pot experiments may not represent field conditions. Liquid/solid partition coefficients (Kd)of 226Ra, U, 210Pb and 210Po for55 soils representing the dominant types of soils in Syria were also determined. Geometric means of Kd values ranged from 280 to1200, 750 to1600, 350to 4800 and 100-120 L kg-1 for 226Ra, 238U, 210Pb and 210Po, respectively at pH = 4.0, and from 200 to 6700, 670 to 2400, 150 to 2100 and 100 to 160Lkg-1at pH = 5.5, and from 370 to 790, 130 to 550, 60 to 330 and370 to 920Lkg-1at pH = 7.0. The effects of soil mineral content, CEC, ECE, pH and soluble ions on the Kd values were investigated. In general, there were logarithmic relationships between the activity concentrations in soil and the Kd values (R2 ranged from 0.59 to 1.00 at pH 4.0). There were no relationships between the Kd values and soil pH.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Radioisótopos/análise , Solo , Poluentes Radioativos do Solo/análise , Síria , Fator de Transferência , Urânio/análise
5.
J Environ Radioact ; 229-230: 106543, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33515923

RESUMO

Data, despite being crucial for internal dose assessment, is lacking on the transfer of artificial radionuclides from the environment to the food supply. Expanding the available information on these factors is important for the improvement of dose models for specific scenarios. This paper describes the results of a 70 day field experiment with broiler chickens on the dynamics of excretion of 137Cs and 241Am from the muscle, liver and bone of broilers after a 30 day application of contaminated feed. The radionuclide concentrations in the feed and the thigh muscle, thigh bone and liver of 54 chickens divided between grass meal and soil contaminated feed groups were evaluated by gamma spectrometry for 241Am and 137Cs. The obtained results confirm previous data on the dynamics of the excretion of cesium from organs, which can be described with a fast and a slow exponential curve of excretion. On the 70th day, following the 30-days application, 2-8% of the first-day activity concentrations of 137Cs in organs (muscle, liver, bone) were detected. In the first two days, activity concentration of 241Am decreases twofold in both liver and bone. 35% of the maximum activity concentration of 241Am remained in bone and 15% in liver on the last day of the experiment.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Ração Animal/análise , Animais , Radioisótopos de Césio/análise , Galinhas , Poluentes Radioativos do Solo/análise
6.
Mar Pollut Bull ; 163: 112009, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33477060

RESUMO

A comprehensive radiological survey using multivariate statistical analysis was carried out to evaluate the distribution of 40K, 232Th, 226Ra, 235U, and 137Cs, and associated radiation indices in beach sand samples of the coastal area of the Aegean Sea. The activity concentration of selected radionuclides was measured and no clue of recent migration of radiocaesium by not only precipitation but also through an indirect way, such as ocean runoff, was found. As part of radiological risk assessment, external radiation hazard index, radium equivalent activity, effective dose, and absorbed dose rate were estimated. Pearson correlation, cluster, and PCA analysis were used by processing observed radiological parameters to determine the correlation between the radiological parameters and locations. Pearson correlation shows a strong association between all parameters and activity of 226Ra and 232Th. A spatial distribution map was provided to a distinct visual representation of the distribution of radionuclide contents in the study area.


Assuntos
Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Radiação de Fundo , Grécia , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Espectrometria gama , Tório/análise
7.
Environ Monit Assess ; 193(1): 34, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33404908

RESUMO

A total of fifty-five soil samples were collected from four locations, namely, residential, industrial, dumpsite, and sewage in Agbara industrial estate, Ogun state, Nigeria. The samples were analyzed using a high purity germanium detector (HPGe) to measure the activity concentration of radionuclides. Background radiation measurements were also taken at each point where soil samples were collected using Geiger Muller (GM) counter. The mean activity concentrations measured in the soil samples were 171.33 for 40K, 9.11 for 232Th, and 5.05 for 226Ra in Bq/kg. The mean absorbed dose rate in the air due to radionuclides (40K, 232Th, and 226Ra) in the soil is calculated to be 14.77 nGy/h, and the mean annual effective dose equivalent (AEDE) is 0.02 mSv/year. The mean equivalent dose rate (EDR) from GM counter for background radiation is 0.22 µSv/h, and the mean annual effective dose rate (AEDR) is 0.39 mSv/year. These values are below the world average values, except EDR and AEDR with mean values higher than the world standard. The comparison of radiation dose rates revealed that radionuclides contributed 6.7% to background radiation. The equivalent dose (EDorgans) for various organs of the body was calculated, and results showed that values do not pose any immediate health hazard. The excess lifetime cancer risk (ELCR) due to exposure to background radiation indicated that the dwellers and industrial workers in the study area may develop cancer over a lifetime due to accumulated dose.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Radiação de Fundo , Monitoramento Ambiental , Humanos , Nigéria , Radioisótopos de Potássio/análise , Doses de Radiação , Radioisótopos/análise , Poluentes Radioativos do Solo/análise , Tório/análise
8.
J Environ Radioact ; 228: 106525, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33401155

RESUMO

This study focuses on evaluating the transfer factor (Fv) of 137Cs and 90Sr from two basic soil types in the country, i.e. Aridisol and Inceptisol, to 18 common crops belong to six groups, i.e. cereals, leafy, non-leafy vegetables, tubers, leguminous fodder and leguminous vegetables. In addition, the variation of Fvs of 137Cs and 90Sr with crop components, growth stages of plants and the influence of mineral fertilisation were investigated. The experiments were performed in an open field and the results were expressed as geometric means. The data revealed that Fvs of both radionuclides were higher in Aridisol than Inceptisol for all crops by about 1.03-4.86 fold. Fvs of 90Sr were more enhanced than those of 137Cs by one or two orders of magnitude despite plant group and soil type, e.g. Fvs ranged 0.12-5.2 for 90Sr and 0.0035-0.26 for 137Cs in the vegetative portion of the crops. Among the six crop groups investigated, cereals gave the lowest Fvs for both radionuclides, which is compatible with the data reported worldwide. The average Fvs observed in cereal grains reached 0.001 for 137Cs and 0.017 for 90Sr, in Inceptisol. However, Jew-mallow (one of the major leafy vegetables in the country that is consumed throughout the year) reflected the highest Fvs for 137Cs and 90Sr, i.e. 0.11 and 2.44 in Inceptisol, respectively. Comparing Fvs of the radionuclides through the growing stages of the plants indicated enhanced values at the mid-season than harvest as a consequence of the decrease of the physiological activity of the plants towards maturation and dilution made by the increase of plant biomass; e.g. Fvs dropped to about 3.0 fold for 137Cs and 2.2 for 90Sr, in Aridisol. Mineral fertilisation of soil (for four crops, i.e. sorghum, barley, spinach and alfalfa) reduced Fvs for both radionuclides to an extent of 30% probably because of the competing action of their stable nutrient analogues NH4+, K+ or Ca2+ or because of growth dilution. The data presented herein would form a baseline when decision of land-investment or phytoremediation is the preferable countermeasure for the management of 137Cs and 90Sr-contaminated soil in semi-arid environment.


Assuntos
Radioisótopos de Césio , Produtos Agrícolas , Monitoramento de Radiação , Poluentes Radioativos do Solo , Radioisótopos de Estrôncio , Radioisótopos de Césio/análise , Poluentes Radioativos do Solo/análise , Fator de Transferência
9.
J Environ Radioact ; 228: 106511, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341752

RESUMO

Corrosion process was investigated of depleted uranium (DU) ammunition fragments buried for three years in aerobic soils continuously irrigated with water. The continuing corrosion process was triggered through formation of soluble uranyl oxyhydrate phases such as metaschoepite and becquerelite, which were identified by micro-Raman and X-ray diffraction spectroscopy. The soil was not amended by phosphates and, therefore, no uranyl phosphates were found as corrosion products on the DU surfaces by X-ray photoelectron spectroscopy. A speciation modelling at high temporal sequence (chronospeciation approach) indicated that the abundant Fe oxyhydroxides in the soil immobilized the U(IV) released through DU corrosion. During the first two years, therefore, only <10 mg of U(VI) was thus found in the leachates from the soil columns, even though >3 g of DU had been corroded. However, the degree of this immobilization was found to be controlled by the amount of dissolved inorganic and organic carbon (DIC and DOC) in the soil pore water providing for U(VI) complexation competing with surface complexation by the Fe hydroxides. The chronospeciation approach applied is useful to improve our understanding and ability to predict the long-term fate of U(VI) and the mechanisms controlling U(VI) mobility in soil contaminated with DU shells.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Corrosão , Solo , Poluentes Radioativos do Solo/análise , Urânio/análise
10.
Chemosphere ; 267: 129171, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33348265

RESUMO

The aim of the study was to evaluate the radiation levels, radiological doses and excess lifetime cancer risk possessed by the urban soils that were collected from the vicinity of the exclusive mining and excavation centers of Dera Ghazi Khan. The high purity germanium detector was utilized for assessment of naturally occurring radionuclides (NORMs) in soil and results showed that the average activity concentrations of 226Ra, 232Th, and 40K (37 Bq/kg, 43.07 Bq/kg, 737 Bq/kg respectively) surpassed the world's average documented values (35 Bq/kg, 30 Bq/kg, and 400 Bq/kg respectively). Moreover, the average values of radiological hazards assessment like radium equivalent, internal and external hazard indices, absorbed dose rate, annual gonadal dose equivalent and excess lifetime cancer risk were 155.70 (Bq/kg), 0.4, 0.5, 73.96 (nGy/h) 90.73 (µSv/y), 476.24 (µSv/y) and 0.31(10-3) respectively. The data acquired was analyzed using descriptive statistics, cluster analysis and principal component analysis. ArcGIS (10.5) software was utilized for developing maps of radionuclide's concentration for the study area. Results of the study may serve as an important baseline radiometric data for future epidemiological studies and monitoring initiatives in the study area.


Assuntos
Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Paquistão , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Medição de Risco , Solo , Poluentes Radioativos do Solo/análise , Espectrometria gama , Tório/análise
11.
J Environ Radioact ; 226: 106458, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33202288

RESUMO

Over 40 soil gas samples were collected both in post-industrial areas as well as in undisturbed areas in the region of Kvarntorp, Sweden. Radioxenon (133Xe) was detected in 15 samples and radioargon was detected in 7 from 10 samples analysed. The concentration of radioxenon and radioargon in soil gas ranged up to 109 mBq/m3 and 19 mBq/m3, respectively. During sample collection other soil gases such as radon, CO2 and O2 were also measured and soil samples were taken along with dose rate measurements. The field experiment presented here shows that it is possible to detect naturally occurring radioxenon and radioargon in soil gas simultaneously.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Radônio/análise , Poluentes Radioativos do Solo/análise , Radioisótopos de Xenônio/análise , Gases/análise , Solo , Suécia
12.
J Environ Radioact ; 226: 106456, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33217723

RESUMO

Understanding the relationship between the distribution of radioactive 134Cs and 137Cs in forests and ambient dose equivalent rates (H˙∗(10)) in the air is important for researching forests in eastern Japan affected by the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. This study used a large number of measurements from forest samples, including 134Cs and 137Cs radioactivity concentrations, densities and moisture contents, to perform Monte Carlo radiation transport simulations for H˙∗(10) between 2011 and 2017. Calculated H˙∗(10) at 0.1 and 1 m above the ground had mean residual errors of 19% and 16%, respectively, from measurements taken with handheld NaI(Tl) scintillator survey meters. Setting aside the contributions from natural background radiation, 134Cs and 137Cs in the organic layer and the top 5 cm of forest soil generally made the largest contributions to calculated H˙∗(10). The contributions from 134Cs and 137Cs in the forest canopy were calculated to be largest in the first two years following the accident. Uncertainties were evaluated in the simulation results due to the measurement uncertainties in the model inputs by assuming Gaussian measurement errors. The mean uncertainty (relative standard deviation) of the simulated H˙∗(10) at 1 m height was 11%. The main contributors to the total uncertainty in the simulation results were the accuracies to which the 134Cs and 137Cs radioactivities of the organic layer and top 5 cm of soil, and the vertical distribution of 134Cs and 137Cs within the 5 cm soil layers, were known. Radioactive cesium located in the top 5 cm of soil was the main contributor to H˙∗(10) at 1 m by 2016 or 2017 in the calculation results for all sites. Studies on the 137Cs distribution within forest soil will therefore help explain radiation levels henceforth in forests affected by the FDNPP accident. The merits of this study are that it modelled multiple forests for a long time period, with the important model inputs being informed by field measurements, and it quantified how the measurement uncertainties in these inputs affected the calculation results.


Assuntos
Radioisótopos de Césio/análise , Florestas , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Japão , Radioatividade
13.
J Environ Radioact ; 226: 106457, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33227677

RESUMO

Radiocesium was dispersed from the Fukushima Dai-ichi disaster in March 2011, causing comparatively high radioactive contamination in nearby environments. Radionuclide concentrations in wild rodents (Apodemus argenteus, and Apodemus speciosus) within these areas were monitored from 2012 to 2016. However, whole-organism to soil transfer parameters (i.e., concentration ratio, CRwo-soil) for wild rodents at Fukushima were not determined and hence were lacking from the international transfer databases. We augmented the 2012-2016 data by collecting soil activity concentrations (Bq kg-1, dry mass) from five rodent sampling sites in Fukushima Prefecture, and developed corresponding CRwo-soil values for radiocesium (134Cs and 137Cs) based on rodent radioactivity concentrations (Bq kg-1, fresh mass). The CRwo-soil were added to the Wildlife Transfer Database (WTD; http://www.wildlifetransferdatabase.org/), supporting the development of the International Commission on Radiological Protection's (ICRP) environmental protection framework, and increasing the WTD from 84 to 477 entries for cesium and Muridae ('Reference Rat'). Significant variation occurred in CRwo-soil values between study sites within Fukushima Prefecture. The geometric mean CRwo-soil, in this paper, was higher than that reported for Muridae species for Chernobyl. Radiocaesium absorbed dose rates were also estimated for wild rodents inhabiting the five Fukushima study sites and ranged from 1.3 to 33 µGy h-1. Absorbed dose rates decreased by a factor of two from 2012 to 2016. Dose rates in highly contaminated areas were within the ICRP derived consideration reference level for Reference Rat (0.1-1 mGy d-1), suggesting the possible occurrence of deleterious effects and need for radiological effect studies in the Fukushima area.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Animais , Radioisótopos de Césio/análise , Japão , Doses de Radiação , Ratos
14.
Sci Total Environ ; 750: 142311, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33182179

RESUMO

Since Fukushima accident, dozens of field studies have been conducted in order to quantify and understand the behaviour of atmospheric radiocesium (137Cs) fallouts in contaminated forests of Fukushima and neighbouring prefectures. In this paper, we carry out a detailed review of data acquired over 2011-2017 in Japanese cedar and cypress plantations, focusing on aerial tree organs, soil layers and tree-to-soil depuration fluxes. To enable comparison and reinforce the consistency between sites, radiological measurements were normalized by the deposit and interpolated onto the same spatio-temporal frame. Despite some (poorly explained) residual variability, we derived a "mean" pattern by log-averaging data among sites. These "mean" results were analysed with the help of a simple mass-balance approach and discussed in the light of post-Fukushima literature. We demonstrated that the activity levels and dynamics in all compartments were consistent and generally well reproduced by the mass balance approach, for values of the interception fraction between 0.7 and 0.85. The analysis indicated that about 5% of the initial deposit remained in the aerial vegetation after 6 years, more than two thirds of intercepted 137Cs being transferred to the soil due to throughfall. The simulations indicated that foliar uptake might have contributed between 40% and 100% to the activity transferred to stem wood. The activity concentration in canopy organs rapidly decreased in the first few months then more slowly, according to an effective half-life of about 1.6 years. The activity level in the organic layer peaked in summer 2011 then decreased according to an effective half-life of 2.2 years. After a rapid increase in 2011, the contamination of mineral horizons continued to increase more slowly, 85% of 137Cs incoming through the organic layer being retained in the 0-5 cm layer according to a mean residence time longer than in the upper layer (7 against 1.5 years).


Assuntos
Cryptomeria , Cupressus , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo , Radioisótopos de Césio/análise , Florestas , Japão , Poluentes Radioativos do Solo/análise
15.
Chemosphere ; 263: 127909, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32822937

RESUMO

236U has attracted more attention as an environmental tracer in recent years. However, in-depth study of 236U in terrestrial environments is still rare in China. Data on 236U and 137Cs concentrations in soil and road dust samples collected from Beijing and Zhangjiakou, China were obtained to demonstrate the background and distinct characteristics of anthropogenic 236U and 137Cs. 236U and 137Cs were detected in the range of (1.10-7.90) × 107 atoms g-1 and below the method limits of detection to 5.30 Bq kg-1. A clear characteristic was observed in road dust, where 236U concentrations increased with decreasing of sample particle size. Soil samples showed an irregular characteristic, but the highest 236U concentrations were observed in particle size fraction of <0.053 mm in both samples. This phenomenon was caused by U chemical properties, higher specific surface areas and organic compounds in fine particles. Anthropogenic radionuclides fingerprint characteristics in <0.053 mm samples were specially discussed. 236U/238U atom ratios were detected in the range of (0.627-3.38) × 10-8. A weak correlation between anthropogenic 236U and natural U isotopes were observed. The intermediate correlation between 236U and 137Cs indicated somewhat distinct migration behavior of these two radionuclides in soil after release to the environment. The released amount of 236U from global fallout during the period of atmospheric nuclear weapons testing was roughly estimated to be 1300 ± 448 kg. These results could be used as fingerprint information for anthropogenic 236U migration behavior and tracer application in environment.


Assuntos
Radioisótopos de Césio/análise , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Urânio/análise , Pequim , China , Poeira/análise , Compostos Orgânicos , Tamanho da Partícula , Solo/química
16.
Chemosphere ; 268: 129336, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33359994

RESUMO

We studied activity concentrations of artificial 137Cs and natural 40K and concentration of total potassium (K) in Boletus edulis at different maturity stages (button, young - white, large - white and large - yellow), and the effect of braising and human dietary intake. Mushrooms were collected from the northern region of Poland in 2019. The 137Cs activity concentration was significantly higher in raw and braised button stage samples and decreased as the fruitbody matured, but conversely, 40K was lower in the raw button stage than in older fruitbodies. 137Cs activity concentrations in raw, button stage B. edulis were 36 ± 1 Bq kg-1 ww (360 ± 1 Bq kg-1 dw), increasing to 70 ± 2 Bq kg-1 ww (290 ± 7 Bq kg-1 dw) when braised. This activity was around fourteen-fold higher (p < 0.0001) than at higher maturity stages which showed 2.5 ± 0.7 Bq kg-1 ww (25 ± 7 Bq kg-1 dw) in raw and 4.9 ± 0.7 Bq kg-1 ww (19 ± 4 Bq kg-1 dw) in braised fruitbodies. In comparison to raw B. edulis, braising enriched the activity concentrations of 137Cs at 110 ± 69% and 40K at 80 ± 56% on a whole (wet) weight basis.


Assuntos
Basidiomycota , Monitoramento de Radiação , Poluentes Radioativos do Solo , Idoso , Radioisótopos de Césio/análise , Humanos , Polônia , Radioisótopos de Potássio/análise , Doses de Radiação , Poluentes Radioativos do Solo/análise
17.
J Environ Radioact ; 228: 106513, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33360017

RESUMO

While radioisotopes of noble gases are known to be indicators of underground nuclear explosions (UNE), McIntyre et al. (2017) was the first to report the presence of 39Ar in shallow soil gas in association with a decades old UNE. While this finding hinted at the potential application of 39Ar to be used as an indicator of a UNE, doing so would also require an understanding of the natural concentrations of 39Ar present in soil gas. Without knowing the expected range and variability of naturally occurring concentrations of 39Ar, it is difficult to determine what measured concentrations would be indicative of an elevated concentration. This paper presents results from 16 soil gas samples and three atmospheric air samples collected from various locations across the western United States. Shallow soil gas samples were collected into self-contained underwater breathing apparatus (SCUBA) tanks using a custom-built soil gas sampling system and then processed and analyzed for 39Ar. The measured concentrations of 39Ar varied from atmospheric air concentrations to about 3.5 times atmospheric air concentrations (58 mBq/m3). The results presented here represent the first measurements of natural background 39Ar concentrations in shallow soil gas. This data will be necessary if 39Ar is to be used as an indicator of UNE.


Assuntos
Argônio , Radiação de Fundo , Monitoramento de Radiação , Radioisótopos , Poluentes Radioativos do Solo/análise , Argônio/análise , Radioisótopos/análise , Solo
18.
Sci Data ; 7(1): 431, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33339821

RESUMO

The majority of the area contaminated by the Fukushima Daiichi Nuclear Power Plant accident is covered with forests. We developed a dataset for radiocaesium (137Cs) in trees, soil, and mushrooms measured at numerous forest sites. The 137Cs activity concentration and inventory data reported in scientific journal papers written in English and Japanese, governmental reports, and governmental monitoring data on the web were collated. The ancillary information describing the forest stands were also collated, and further environmental information (e.g. climate) was derived from the other databases using longitude and latitude coordinates of the sampling locations. The database contains 8593, 4105, and 3189 entries of activity concentration data for trees, soil, and mushrooms, and 471 and 3521 entries of inventory data for trees and soil, respectively, which were collected from 2011 to 2017, and covers the entire Fukushima prefecture. The data can be used to document and understand the spatio-temporal dynamics of radiocaesium in the affected region and to aid the development and validation of models of radiocaesium dynamics in contaminated forests.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Poluentes Radioativos do Solo/análise , Agaricales/química , Monitoramento Ambiental , Florestas , Japão , Solo/química , Análise Espaço-Temporal , Árvores/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-33322400

RESUMO

222Rn is a specific indoor-type pollutant that represents a primary radiological hazard as a main source of ionizing radiation (IR) for humans. Coal mining creates new sources of gas that are formed over mines. This process can significantly increase the density of radon flux. Therefore, the concentration of radon in a room can increase. We investigated the territory of the Leninsk-Kuznetsky district of the Kemerovo region, which is subject to underground mining. Two groups of residential locations and measuring points of radon flux density were selected to identify the higher emanation relationship of radon and mining-affected areas. The first group (Case group) included subjects located within the territory of the underground mine; the other (Control group) included subjects in an area without mining. Radon flux density in coal mining areas was significantly higher than in the rest of the territory; moreover, the percentage of values in the Case group that had a radon flux density above 80 mBq·m-2·s-1 was 64.53%. For the Case group, 20.62% of residential buildings had a radon concentration above 200 Bq/m3. For the studied area, the radon flux density correlates positively (r = 0.79, p = 0.002) with indoor radon. Additional clastogenic/aneugenic effects are also found in dwellings with increased volume activity of radon (VAR) within the territories of underground mines. Ring chromosomes are positively correlated with radon levels in smoker groups but not in non-smokers. An increased frequency of binucleated (BN) cells with micronuclei (MN) is also positively correlated with VAR regardless of smoking status. It has been concluded that reducing the total exposure level of a population to radon can be achieved by monitoring areas with underground mines where radon is emitted heavily.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Solo , Adulto , Poluentes Radioativos do Ar/análise , Humanos , Masculino , Pessoa de Meia-Idade , Mineração , Radônio/análise , Solo , Poluentes Radioativos do Solo/análise
20.
Environ Monit Assess ; 192(12): 775, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33219883

RESUMO

The activity concentration of natural radionuclides in farm soil and most common indigenous food crops (maize, potato, cowpea) in oil-producing (Philippi, Uitenhage, and Hertenbos farms) and non-oil-producing (Ukulinga farm) areas of South Africa was measured using a Hyper Pure Germanium detector. Consequently, the transfer of these radionuclides from soil-to-crops was estimated. The mean activity concentration of 226Ra, 232Th, and 40K for farm soil samples are 30.71 ± 11.77, 31.97 ± 8.90, 345.97 ± 98.62 Bq.kg-1 for Philippi; 18.67 ± 6.70, 31.55 ± 11.48, 191.93 ± 33.39 Bq.kg-1 for Uitenhage; 38.03 ± 17.44, 41.18 ± 31.54, 381.89 ± 163.40 Bq.kg-1 for Hartenbos; and 8.47 ± 2.87, 8.65 ± 3.52, 94.22 ± 25.97 ± 25.97 Bq.kg-1 for Ukulinga. The mean activity concentration of 226Ra, 232Th, and 40K for crop samples are 4.54 ± 1.47, 4.87 ± 1.69, 140.18 ± 35.38 Bq.kg-1 for Philippi; 9.17 ± 4.79, 3.85 ± 1.87, 136.75 ± 22.04 Bq.kg-1 for Uitenhage; 7.97 ± 2.91, 4.62 ± 2.40, 105.97 ± 48.65 Bq.kg-1 for Hartenbos; and 4.23 ± 1.63, 2.72 ± 1.19, 48.36 ± 15.55 Bq.kg-1 for Ukulinga. The activity concentration and soil-to-crop transfer factors for 40K were found to be much higher, possibly because this element is critical in crop growth. The results showed that the crop samples' transfer factor is in the order cowpea>potato>maize. This study showed that activity concentrations of 226Ra, 232Th, and 40K in crops and the corresponding transfer factors depend on activity concentrations of the same radionuclides in soil.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Monitoramento Ambiental , Fazendas , Radioisótopos/análise , Solo , Poluentes Radioativos do Solo/análise , África do Sul
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