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1.
J Environ Radioact ; 273: 107392, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342022

RESUMEN

The measurement of 226Ra and the identification of 226Ra-bearing minerals are important for studying the behavior of radium in the environment. Various instruments for measuring 226Ra are currently used: among the radiometric techniques that measure in bulk (no spatialization), there are gamma spectrometers and alpha spectrometers. Other instruments such as SEM-EDS can map the chemical elements thus providing information on the distribution of 226Ra, but are limited for ultra-trace analyses on natural geomaterials. Finally, autoradiography techniques can locate radioactivity, but are limited to the identification of the contribution of 226Ra when the 238U series is complete. This study focuses on spectroscopic autoradiography, a method for measuring both the energy of the alpha particle emissions and their positions on the autoradiograph. A gas detector based on a parallel ionization multiplier technology was used for this purpose. Alpha particle energy is dependent on the emitting radionuclides. In order to track the 226Ra, the energy spectrum of the 238U series was studied with modeling software. It appears possible to apply a thresholding on the energy spectrum to discriminate the 226Ra from the first alpha emitters of the 238U decay chain (i.e. 238U, 234U and 230Th, all below 5 MeV). The developed method was applied to a U-mill tailing sample prepared as a thin section. The sample was heterogeneous in terms of radioactivity and was not at secular equilibrium with 238U, as expected. The 226Ra was identified and localized, and different regions of interest were also analyzed with SEM-EDS elements cartography. This revealed 226Ra-rich barite (BaSO4) phases measured at 3 ppmRa on average and containing no uranium; and uranium in siderite (FeCO3), showing a strong 226Ra deficit compared with secular equilibrium. Spectroscopic autoradiography opens up possibilities for the analysis of heterogeneous geological samples containing natural alpha emitters such as 238U and 226Ra: the 226Ra can be localized and quantified at ultra-trace content, and the method developed can also identify newly (young) uranium phases by measuring 238U/226Ra activity disequilibrium.


Asunto(s)
Monitoreo de Radiación , Radio (Elemento) , Uranio , Autorradiografía , Uranio/análisis , Partículas alfa , Monitoreo de Radiación/métodos , Radioisótopos/análisis , Radio (Elemento)/análisis
2.
Sci Total Environ ; 912: 168934, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38048999

RESUMEN

In Europe, the general obligation to recycle drives for increased reuse of residues containing Naturally Occurring Radioactive Material (NORM). In agriculture, this has led to the reuse of sludge produced by groundwater filtration facilities as a means of fertilization. In the frame of the RadoNorm project, a methodology was developed for dose assessment of agricultural workers and other members of the public living near agricultural fields in which NORM-containing sludge is applied. Appropriate exposure scenarios were identified and modelled for each relevant NORM decay segment of both U-238 and Th-232 series, as well as for K-40. Dose assessments were performed using the software RESRAD-ONSITE with dose coefficients for external and internal exposure taken from the latest publications from the International Commission on Radiological Protection (ICRP). The objective was to develop a generic methodology to quantify exposure and to obtain screening values - so-called Operational Levels (OLs). These OLs pertain to the activity concentration of natural radionuclides (in terms of kBq kg-1) present in sludge that is reused in agriculture, for which dose criterion of 1 mSv year-1 is complied with. OLs can be used as screening tools by an authority/operator, even non-experts in the field of radiation protection. Results showed that the most critical decay segments are Ra-226+ and Ra-228+, for which OLs of the order of 1 kBq kg-1 were estimated. For all the other radionuclides, the calculated OLs are much higher than the activity concentrations typically found in sludge from water treatment facilities, and the radiological impact expected is well-below 1 mSv year-1. The methodology and results of this study could contribute to the update of the Clearance Levels and discharge levels reported in the European guidelines RP 122 Part II and RP 135, respectively.


Asunto(s)
Monitoreo de Radiación , Uranio , Humanos , Aguas del Alcantarillado , Fertilizantes , Radioisótopos/análisis , Monitoreo de Radiación/métodos
3.
J Environ Radioact ; 270: 107292, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37703597

RESUMEN

Nuclear industrial archaeology utilises radiation mapping and characterisation technologies to gain an insight into the radiological footprint of industrial heritage sites. Increased concentrations of naturally occurring radioactive materials at legacy mine sites are the result of elemental enrichment during coal mining and subsequent combustion. Public safety is of concern around these sites, and therefore, an increased understanding of their associated hazard is essential. Using coincident laser scanning and gamma detection technologies, this study sought to assess the radiological legacy of a coal mine located in Bristol, UK. From this, we can increase our understanding of the residual footprints associated with the local coal mining industry. Samples taken from inside the site were characterised using high resolution gamma spectrometry, wherein the radionuclide content and activities of samples were then quantified. An area of elevated low-level radioactivity was observed at and around buildings believed to belong to the colliery, while Th, U, and K are confirmed at the site from photopeak's of daughter radionuclides. Activities of the radionuclides K-40, U-238, and Th-232 were further quantified during subsequent laboratory analysis. Results highlight an enrichment of naturally occurring radionuclides when compared with global averages for unburned coal. Employing these techniques at further legacy sites would enable an increased understanding of the lasting traces of the coal mining industry, with a focus on NORM enrichment in residual fly ash.


Asunto(s)
Minas de Carbón , Monitoreo de Radiación , Uranio , Monitoreo de Radiación/métodos , Uranio/análisis , Arqueología , Radioisótopos/análisis , Ceniza del Carbón/análisis , Carbón Mineral/análisis
4.
Appl Radiat Isot ; 200: 110939, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37536028

RESUMEN

In this study, natural radioactivity levels (226Ra, 232Th, and 4 K) of some medicinal plant samples with known anti-oxidative properties, which are frequently consumed by animals and humans, were obtained from Ankara province and its surroundings (Mamak, Kizilcahamam, Beypazari, Kahramankazan, and Polatli districts) were determined using a thallium-doped sodium iodide NaI(Tl) gamma spectrometry. By using the determined natural radioactivity concentrations in the collected plant samples, the number of radiological doses that people could be exposed by consuming these plants was calculated. As a result of the study, 226Ra, 232Th, and 4 K radioactivity concentration ranges of the plant samples were found be 14.69 ± 1.27-59.08 ± 3.12 Bq kg-1, 1.78 ± 0.04-50.05 ± 2.76 Bq kg-1 and 207.24 ± 34.09-826.13 ± 25.40 Bq kg-1, respectively. The highest 226Ra, 232Th, and 4 K activity concentrations were measured in Astragalus densifolius subsp. ayashensis (Kahramankazan), Astragalus kochakii (Kahramankazan) and Rumex patientia (Patience Dock) (Kahramankazan) plants, respectively. The lowest 226Ra, 232Th and,4 K activity concentration plants were determined respectively as Rumex patientia (Mamak), Lavandula angustifolia (Kizilcahamam), and Astragalus acikirensis (Polatli). The establishment and routine repetition of environmental radioactivity monitoring programs in each region are important for human and animal health, and the results of this study gain importance for Ankara and its surroundings in terms of environmental health.


Asunto(s)
Monitoreo de Radiación , Radiactividad , Radio (Elemento) , Contaminantes Radiactivos del Suelo , Humanos , Radioisótopos/análisis , Monitoreo de Radiación/métodos , Turquía , Espectrometría gamma/métodos , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Potasio/análisis , Radio (Elemento)/análisis , Torio/análisis
5.
J Environ Radioact ; 268-269: 107246, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37506478

RESUMEN

In this study, we present an assessment of the uranium ore tailings impact on groundwater and surface water contamination. The radioactive materials were deposited in the tailings storage facility "Dniprovske" (the city of Kamianske, Ukraine) from 1954 to 1968; now it contains about 5.85·106 m3 of hazardous waste on the area of about 76 ha in the floodplain of the Dnipro river. The lack of a proper waterproof screen below deposited tailings and in the earthen dam led to permanent watering of radioactive materials, their leaching and migration in groundwater into the nearest small Konoplianka river. We used the reports on previous site-specific studies conducted in 1999-2016, monitoring results, and the field studies conducted in 2022 with the authors' team participation. The calculations performed with the advection-dispersion model to simulate transport of radionuclides 238U, 230Th, 226Ra and 210Pb through the embankment to the Konoplianka river and dilution relations were compared to the monitoring data of the surface water quality. Among four radionuclides, uranium poses the greatest risks today; the subsurface runoff increases its concentration in the Konoplianka river water by several times over the background value. It is estimated that due to much more intensive sorption in the shallow aquifer, the contribution of 226Ra and 210Pb to the increase in radioactivity of Konoplianka river water is insignificant compared to uranium, whereas the migration front of 230Th has probably not yet reached the riverbank. In the next 50 years the radionuclide fluxes will increase by 1.3-3.7 times for different isotopes, with the uranium subsurface runoff growing at a slower rate than nowadays. These results are of high significance for improving hydrological, hydrogeological, and geotechnical monitoring on this hazardous facility to maintain its radiation safety.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Uranio , Contaminantes Radiactivos del Agua , Uranio/análisis , Ucrania , Plomo , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos/análisis , Contaminantes Radiactivos del Agua/análisis
6.
Ecotoxicol Environ Saf ; 263: 115210, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37418943

RESUMEN

This study investigated the distribution features of uranium-238 (238U), radium-226 (226Ra), thorium-232 (232Th), and potassium-40 (40K) and evaluated the associated environmental radiological hazards of the topsoil and river sediments in the Jinding lead-zinc (Pb-Zn) mine catchment from Southwest China. The activity concentrations of 238U, 226Ra, 232Th, and 40K ranged from 24.0 ± 2.29-60.3 ± 5.26 Bq.kg-1, from 32.5 ± 3.95-69.8 ± 3.39 Bq.kg-1, from 15.3 ± 2.24-58.3 ± 4.92 Bq.kg-1, and from 203 ± 10.2-1140 ± 27.4 Bq.kg-1, respectively. The highest activity concentrations for all these radionuclides were primarily found in the mining areas and decreased with increasing distance from the mining sites. The radiological hazard indices, including radium equivalent activity, absorbed gamma dose rate in the air, outdoor annual effective dose equivalent, annual gonadal dose equivalent, and excess lifetime cancer, revealed that the highest values were observed in the mining area and downstream, specifically in the vicinity of the ore body. These elevated values exceeded the global mean value but remained below the threshold value, suggesting that routine protection measures for Pb-Zn miners during production activities are sufficient. The correlation analysis and cluster analysis revealed strong associations between radionuclides such as 238U, 226Ra, and 232Th, indicating a common source of these radionuclides. The activity ratios of 226Ra/238U, 226Ra/232Th, and 238U/40K varied with distance, suggesting the influence of geological processes and lithological composition on their transport and accumulation. In the mining catchment areas, the variations in these activity ratios increased indicated the impact of limestone material dilution on the levels of 232Th, 40K, and 238U in the upstream region. Moreover, the presence of sulfide minerals in the mining soils contributed to the enrichment of 226Ra and the removal of 238U caused those activity ratios decreased in the mining areas. Therefore, in the Jinding PbZn deposit, the patterns of mining activities and surface runoff processes in the catchment area favored the accumulation of 232Th and 226Ra over 40K and 238U. This study provides the first case study on the geochemical distributions of natural radionuclides in a typical Mississippi Valley-type PbZn mining area and offers fundamental information on radionuclide migration and baseline radiometric data for PbZn deposits worldwide.


Asunto(s)
Monitoreo de Radiación , Radio (Elemento) , Contaminantes Radiactivos del Suelo , Uranio , Suelo , Plomo/análisis , Zinc/análisis , Radioisótopos/análisis , Uranio/análisis , Radio (Elemento)/análisis , Torio/análisis , Contaminantes Radiactivos del Suelo/análisis , Minería
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(6): 826-830, 2023 Jun 06.
Artículo en Chino | MEDLINE | ID: mdl-37357198

RESUMEN

The radioactive safety of drinking water has attracted increasing public concern. The newly issued Standards for Drinking Water Quality (GB5749-2022) in China has revised the radiological parameters. This article provides an overview of the main sources, levels of radionuclides in drinking water, and summarized the individual doses criterion and adverse health effects associated with exposure of the public to radionuclides from drinking-water. It analyzes and discusses the relevant revision content of radiological parameters, including the guidance values for screening gross α and gross ß, subtracting the contribution of potassium-40 from gross ß activity when the gross ß activity concentration exceeds the screening level, and the basis for establishing the limit values of reference indices uranium and radium-226. Specific implementation and evaluation suggestions are also proposed.


Asunto(s)
Agua Potable , Uranio , Humanos , China , Radioisótopos/análisis , Uranio/análisis , Abastecimiento de Agua
8.
Radiat Prot Dosimetry ; 199(12): 1310-1323, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37345708

RESUMEN

During the early response to large-scale radioactive contamination events, people who are potentially affected need to be screened for radioactive contamination and public health staff need to triage individuals who may need immediate decontamination. This is typically done by screening individuals for external contamination using ionising radiation detection equipment. In this study, spatially and temporally dependent isotopic compositions from a simulated nuclear detonation and Monte Carlo methods were used to relate contamination activity levels to the measurable radiation levels at select distances away from an individual with whole-body contamination. Radionuclide-specific air kerma rate coefficients and Geiger-Mueller instrument response coefficients at five select distances from contaminated individuals are presented for 662 radionuclides. Temporally and spatially dependent incident-specific coefficients are presented for a hypothetical surface detonation of a 235U-fueled device.


Asunto(s)
Monitoreo de Radiación , Uranio , Humanos , Radioisótopos/análisis , Triaje/métodos , Dosis de Radiación
9.
J Environ Radioact ; 264: 107189, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37167645

RESUMEN

The study is focused on the hydrogeological conditions and the chemistry of groundwater of the Vendian aquifer in the western part of the Leningrad oblast (Karelian Isthmus and the area near Sosnovy Bor town) and St. Petersburg City, where groundwater features higher radioactivity, but nevertheless it is used for drinking water supply. Data on the radiological characteristics, which have been determined in the estimation of the quality of groundwater used for drinking are generalized and analyzed. These characteristics include the gross alpha and gross beta activity and the specific activity of natural radionuclides 222Rn, 226Ra, 228Ra, 210Pb, 210Po, 238U, and 234U. The data were subjected to statistical and correlation analysis to determine the hygienic criteria for the use of groundwater of this aquifer for drinking water supply and to study the sources and the processes of formation of the natural radiological background. Groundwater quality standards were shown to be exceeded in the majority of the analyzed wells. The brackish water in the southern, deeper, part of the aquifer system was shown to have higher radioactivity and relatively high concentrations of 226Ra, 228Ra, 210Pb, and 210Po, compared with fresh water in the northern part of the territory, of which higher, though nonuniform, 222Rn activity is typical. Relationships between the radiation characteristics of groundwater are considered along with the causes of formation of groundwater radionuclide composition as a result of the higher radioactivity of the host deposits and the chemistry of groundwater; changes in the radiological and hydrochemical background groundwater characteristics from the north to the south are characterized in accordance with the subsidence of the aquifer system and an increase in the stagnation of the hydrochemical regime. The analysis of the well-known relationship between the concentrations of radium isotopes in groundwater, uranium and thorium isotopes in the host rocks, and groundwater residence time in the aquifer, along with the comparison of the available field data with calculation results, suggested the conclusion that the concentration of uranium in the water-bearing rocks in the major portion of the area under consideration is higher than its regional mean values.


Asunto(s)
Agua Potable , Agua Subterránea , Monitoreo de Radiación , Radiactividad , Uranio , Contaminantes Radiactivos del Agua , Uranio/análisis , Agua Potable/análisis , Monitoreo de Radiación/métodos , Plomo/análisis , Contaminantes Radiactivos del Agua/análisis , Agua Subterránea/química , Radioisótopos/análisis , Federación de Rusia
10.
Environ Sci Pollut Res Int ; 30(24): 65379-65391, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37084045

RESUMEN

Uranium mining causes several radiological impacts on the surrounding environment, notably in the water bodies, mainly due to the release of long half-life radionuclides from the 238U and 232Th series. The Ore Treatment Unit, an old uranium mine undergoing decommissioning, has three points of liquid effluent release (#014, #025, and #076). For current study, 78 samples of water were collected at #014, 33 samples at #025, and 63 samples at #076. The radionuclides were analyzed by gross alpha count, gross beta count, and by arsenazo spectrophotometry. Analyses were carried out using the radiological water quality criterion established by World Health Organization and other organizations, together with the Brazilian legislation, to assess if the released effluents may be used unrestrictedly by the individuals of the public. At #014, the mean values of activity concentration (AC), in Bq·L-1, were as follows: Unat = 0.107, 226Ra = 0.035, 210Pb = 0.031, 232Th = 0.007, and 228Ra = 0.049. At #025 the mean values of AC, in Bq·L-1, were as follows: Unat = 0.086, 226Ra = 0.015, 210Pb = 0.028, 232Th = 0.006, and 228Ra = 0.032. Finally, at point #076, the mean AC values, in Bq·L-1, were as follows: Unat = 3.624, 226Ra = 0.074, 210Pb = 0.054, 232Th = 0.013, and 228Ra = 0.069. The current study showed that natural radionuclides were not in secular equilibrium. Despite uranium presented its values outside the limits of guidance levels, it can be state that the unrestricted use of effluents released in the three water bodies is authorized from the radiological point of view. In terms of dose rate, the releases at three points were within the radiological limits of potability. On the other hand, in an additional analysis, #76 presented chemical toxicity above the authorized value, pointing the need of restricted use of water from the point of view of chemical toxicity.


Asunto(s)
Monitoreo de Radiación , Uranio , Humanos , Uranio/análisis , Calidad del Agua , Brasil , Plomo/análisis , Radioisótopos/análisis
11.
Environ Monit Assess ; 195(5): 620, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37106210

RESUMEN

The current study analyzed and interpreted airborne radiometric data from Ilesha's basement complex rock and its surroundings. At the surface, the concentrations of the most frequent primordial radionuclides notably K, elemental concentration of uranium eU, and elemental concentration of thorium eTh were measured. The weighted mean elemental and activity concentrations were 0.85%, 2.75 ppm, 10.22 ppm, and 267.54 Bq kg-1, 34.41 Bq kg-1, 41.51 Bq kg-1 for 40 K, 238U, and 232Th, respectively. The low concentration of 40 K was certainly due to the effects of weathering, kaolinization of granites, and pedogenesis activities. The abundance of uranium was ascribed to the availability of uranium minerals such as allanite, apatite, and sphene with accessories minerals, while that of thorium was due to minerals such as cheralite, thorite, uranothorite, thorianite, and uranothorianite with accessories minerals. The RPHR weighted mean 1.48 µWm-3 compared to the earth's crust mean between 0.8 and1.2 µWm-3 was higher due to significant presence of gneiss rocks in all the studied profiles. Radiological hazard, in particular, dose rates, external hazard index, internal hazard index, radium equivalent, annual gonadal dose, effective dose dispensed to various organs of the body were computed to determine the deleterious effects of rocks in the area. The weighted means of annual gonadal dose of 363.98 µSv y-1 and outdoor 0.91 × 10×3 and indoor 1.65 × 10-3 excessive life cancer risks were more than the global average 300 µSv y-1, 0.29 × 10-3 and 1.16 × 10-3. As a result, proper surveillance is required in the area in order to prevent epidemics occurrence in future.


Asunto(s)
Monitoreo de Radiación , Radio (Elemento) , Contaminantes Radiactivos del Suelo , Uranio , Monitoreo del Ambiente , Torio/análisis , Uranio/análisis , Radioisótopos/análisis , Minerales/análisis , Radio (Elemento)/análisis , Radioisótopos de Potasio/análisis , Contaminantes Radiactivos del Suelo/análisis , Espectrometría gamma , Radiación de Fondo
12.
J Environ Manage ; 340: 117993, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37094385

RESUMEN

From a radioecological perspective, increasing attention has been paid to the long-term stabilisation of decommissioned uranium mill tailings (UMT) repositories. However, little is known about the evaluation of decommissioning and remedial effects of UMT repositories from a microecological perspective based on bacterial communities. Here, we analysed the distribution and structure of soil community assemblies along different vertical soil profiles in a decommissioned UMT repository and explored the impact of soil properties, including physicochemical parameters, metal(loid)s, and radionuclides, on the bacterial assemblage. We found that the α diversity of the bacterial community was unaffected by variations in different soil profiles and taxa were classified at the phylum level with small significant differences. In contrast, the bacterial community structure in and around the UMT repository showed significant differences; however, this difference was significantly affected by soil metal(loid)s and physicochemical properties rather than soil radionuclides. In addition, seven bacterial genera with significant differences between the inner and surrounding regions of the repository could be used as potential indicators to further investigate the remedial effects on soil environmental quality. These findings provide novel insights into the construction of an assessment system and in situ biomonitoring of UMT repositories from a microecological perspective based on bacterial communities.


Asunto(s)
Uranio , Uranio/análisis , Radioisótopos/análisis , Bacterias , Suelo/química
13.
Radiat Prot Dosimetry ; 199(10): 1057-1062, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37056039

RESUMEN

The natural radioactivity in our living environment is mainly due to radionuclides of 40K, 232Th and 238U. We studied the distribution of these radionuclides in the sediment of different rivers and streams throughout the Kathmandu valley. The activity concentrations were determined by using digiBase NaI(TI) gamma-ray spectrometer, and further they were used to calculate radiological hazard indices to estimate the risk associated with the use of these sediments. The average activity concentrations for 40K, 232Th and 238U were found to be 378.54 ± 109.06, 45.95 ± 18.47 and 26.90 ± 9.61 Bq per kg, respectively. The average concentrations and calculated hazard indices have been compared with the respective reported activity concentration in different countries. This study reveals that there is no radiological threat using these local sediments as building materials and for other purposes.


Asunto(s)
Monitoreo de Radiación , Uranio , Torio/análisis , Uranio/análisis , Ríos , Nepal , Radioisótopos/análisis , Radioisótopos de Potasio/análisis
14.
J Environ Radioact ; 259-260: 107124, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36724575

RESUMEN

Gross alpha, a measurement of radioactivity in drinking water, is the most frequent laboratory test to exceed primary drinking water standards among wells tested under the New Jersey Private Well Testing Act (NJ PWTA). Certain geological factors prevalent in New Jersey (NJ) are primarily responsible for the presence of radioactivity in private well drinking water and thus, many of the estimated one million private well users in NJ may be at-risk of water contamination from naturally occurring radionuclides. Neighbor-based private well outreach methodology was utilized to identify high risk wells in both northern and southern NJ regions and offer free private well testing for radionuclides. Previously tested wells with gross alpha exceeding or equal to 3.7 becquerels per liter (Bq L-1; 100 pCi/L) were selected (n = 49) to identify neighbors (n = 406) within 152.4 m (500 feet). Invitation letters were mailed to selected neighbors and some of the previously tested high wells (n = 12) offering free water sampling for the following parameters: gross alpha (48-hour rapid test), combined radium-226 and radium-228 (Ra-226 + Ra-228), uranium-238 (U-238), radon-222 (Rn-222) and iron. Overall, 70 neighbors and 5 high PWTA wells participated in this free water testing opportunity. For neighboring wells, gross alpha results revealed 47 (67.1%) wells exceeding the gross alpha MCL of 0.555 Bq L-1 (15 pCi/L) mainly due to radium activity in the raw/untreated water. Of those with water treatment (n = 62), 12 (19.4%) treated water samples exceeded the gross alpha MCL. Targeting neighbors of known highly radioactive wells for private well testing is an effective public health outreach method and can also provide useful insight of regional contaminant variations.


Asunto(s)
Agua Potable , Monitoreo de Radiación , Radiactividad , Radio (Elemento) , Radón , Uranio , Contaminantes Radiactivos del Agua , Abastecimiento de Agua , Uranio/análisis , Monitoreo de Radiación/métodos , Pozos de Agua , Radioisótopos/análisis , Contaminantes Radiactivos del Agua/análisis , Radio (Elemento)/análisis
15.
Health Phys ; 124(5): 431-437, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36661893

RESUMEN

ABSTRACT: Appendix D of Title 40 Part 61 of the US Code of Federal Regulations (CFR) provides a procedure that US Department of Energy (US DOE) facility owners and operators can use to estimate radionuclide emissions to the atmosphere for dose calculations instead of measuring emissions for minor sources under the 40 CFR Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, regulation. The procedure assumes that any radioactive material heated above 100 °C is completely vaporized and emitted to the atmosphere. In 1991, the US DOE Oak Ridge Reservation (ORR) requested approval to use different release fractions (RFs) for uranium because of its high melting and boiling points. In response to the request, the US Environmental Protection Agency (US EPA) Region IV approved the use of modified RFs for elemental uranium provided no reaction had taken place to alter its chemical form. In 2015, the ORR requested approval to use different RFs for tungsten, again because of its high melting and boiling points. EPA Region IV approved the use of modified RFs for heated radioactive tungsten metal. In accordance with the two precedents set for heating uranium and radioactive tungsten metals, in 2016, the ORR requested approval to use modified RFs in a similar fashion for other radioactive solid metals and compounds with melting and boiling points above 500 °C that might be heated above 100 °C in future research projects and experiments. EPA Region IV again granted approval to use modified RFs for the list of compounds. This note discusses the proposed modified RFs and their development.


Asunto(s)
Contaminantes Radiactivos del Aire , Radón , Uranio , Tungsteno , Radioisótopos/análisis , Contaminantes Radiactivos del Aire/análisis
16.
Radiat Prot Dosimetry ; 199(2): 95-106, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36426758

RESUMEN

In this present study, the activity concentration of the naturally occurring radionuclides 238U, 232Th and 40K have been measured in commonly used chemical fertilizers for agriculture by using gamma-ray spectrometry with NaI (TI) detector. Radiological hazard parameters have been calculated for samples. The mean specific activity concentration of the 238U, 232Th and 40K is 176, 5.75 and 4136 Bq kg-1, respectively. Particularly, the mean value of 238U, as well as 40K, is higher than the world recommended value. Also, the average value of radium equivalent activity is 503 Bq kg-1 and the absorbed dose rate (DR) is 282.93 nGyh-1, which is greater than the permissible limit, whereas the annual effective dose rate (AEDR) is 0.316 mSvy-1, which is lower than the world recommended value. Therefore, collected fertilizer samples significantly increase the activity concentration of natural radionuclides in the agricultural soils. Multivariate statistical techniques such as Pearson correlation and factor analysis are carried out for radioactive variables to understand the existing relationship between them. From obtained results reveals that these fertilizer samples increases the probability of adverse health effects due to natural radioactivity.


Asunto(s)
Monitoreo de Radiación , Radio (Elemento) , Contaminantes Radiactivos del Suelo , Uranio , Torio/análisis , Fertilizantes/análisis , Uranio/análisis , Radioisótopos de Potasio/análisis , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Agricultura , Radio (Elemento)/análisis
17.
Chemosphere ; 310: 136908, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36270528

RESUMEN

The aim of the research was to study seasonal variations in gamma radiation and the statistical significance of these variations. Moreover, we compared in-situ and laboratory analyses of uranium, thorium, radium and potassium K-40 contents. Exposure to a low level of radiation is a minor (but still is) contributor to overall cancer risk therefore we compared doses generated by gamma radiation with overall cancer risk. The research was performed in SW Poland in two granitoid massifs -Strzelin and Karkonosze. The in-situ measurements were performed seasonally using gamma-ray spectrometer Exploranium with BGO detector and Radiometer RK-100. The laboratory measurements were performed using spectrometer with HPGe detector Canberra-Packard and alpha spectrometry technique. The general trend of seasonal variations of natural radionuclides, terrestrial ambient gamma dose (TGDR) and ambient gamma dose rate (AGDR) was difficult to identify. We noticed slightly increased values of all analysed parameters in warmer seasons, and lower in colder, although there were some exceptions. These exceptions were induced by precipitation and varied soil water content, but variations were mostly not statistically significant. The statistically important deviation from the trend was registered only in equivalent uranium data when the survey was carried out during or just after intensive precipitation. We observed a good positive correlation between in-situ and laboratory results (TGDR in situ/Lab r = 0.696), therefore, we recommend using in-situ measurements in a dense measuring grid before collecting selected soil samples to better evaluate the level of natural radiation in the environment. The average ambient gamma dose in the Karkonosze Massif was 0.52 mSv y-1 whereas in the Strzelin Massif was 0.39 mSv y-1. The overall cancer risk in Karkonoski county is higher than in Strzelin county. A connection between increased gamma radiation and higher overall cancer risk is possible but should be examined during more elaborated research.


Asunto(s)
Neoplasias , Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Uranio , Humanos , Estaciones del Año , Uranio/análisis , Contaminantes Radiactivos del Suelo/análisis , Espectrometría gamma/métodos , Rayos gamma , Monitoreo de Radiación/métodos , Radioisótopos de Potasio/análisis , Radiación de Fondo , Torio/análisis , Radioisótopos/análisis , Suelo/química
18.
Environ Geochem Health ; 45(6): 2663-2689, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36097208

RESUMEN

Several anthropogenic activities produce radioactive materials into the environment. According to reports, exposure to high concentrations of radioactive elements such as potassium (40K), uranium (238U and 235U), and thorium (232Th) poses serious health concerns. The scarcity of reviews addressing the occurrence/sources, distribution, and remedial solutions of radioactive contamination in the ecosystems has fueled data collection for this bibliometric survey. In rivers and potable water, reports show that several parts of Europe and Asia have recorded radionuclide concentrations much higher than the permissible level of 1 Bq/L. According to various investigations, activity concentrations of gamma-emitting radioactive elements discovered in soils are higher than the global average crustal values, especially around mining activities. Adsorption technique is the most prevalent remedial method for decontaminating radiochemically polluted sites. However, there is a need to investigate integrated approaches/combination techniques. Although complete radionuclide decontamination utilizing the various technologies is feasible, future research should focus on cost-effectiveness, waste minimization, sustainability, and rapid radionuclide decontamination. Radioactive materials can be harnessed as fuel for nuclear power generation to meet worldwide energy demand. However, proper infrastructure must be put in place to prevent catastrophic disasters.


Asunto(s)
Elementos Radiactivos , Monitoreo de Radiación , Residuos Radiactivos , Contaminantes Radiactivos del Suelo , Uranio , Residuos Radiactivos/prevención & control , Ecosistema , Radioisótopos/análisis , Suelo/química , Uranio/análisis , Contaminantes Radiactivos del Suelo/análisis , Monitoreo de Radiación/métodos
19.
J Hazard Mater ; 441: 129880, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36067557

RESUMEN

Coal ash deposited in open landfills is a potential source of environmental pollutants due to the contained toxic element content. The weathered coal ash used in this study additionally contains enhanced activity concentrations of 238U series radionuclides. This study aimed to determine the physiological effects of enhanced ionizing radiation and toxic elements on five plant species (smilo grass, sticky fleabane, blackberry, mastic and pine tree) inhabiting the coal ash disposal site. Among the potentially toxic measured elements, contents of Sb, As and especially V significantly exceeded their respective levels at the control site, as well as the content of 238U and its progenies. Significant changes in photosynthetic pigments were recorded following chronic exposure to the plants growing on the coal ash site. Different responses were also observed in the plant species regarding the activity of catalase and glutathione-S-transferase (GST). The level of lipid peroxidation markedly increased in plants from the disposal site, except in blackberry, wherein GST activity was the strongest, indicating an important role of that enzyme in the adaptation to coal ash pollutants. The results of this study suggest that the modulation of the studied biochemical parameters in plants growing on coal ash is primarily species-dependent.


Asunto(s)
Contaminantes Radiactivos del Aire , Uranio , Contaminantes Radiactivos del Aire/análisis , Catalasa , Carbón Mineral/análisis , Ceniza del Carbón/análisis , Ceniza del Carbón/toxicidad , Glutatión , Plantas , Centrales Eléctricas , Radioisótopos/análisis , Transferasas , Uranio/toxicidad
20.
Artículo en Chino | WPRIM | ID: wpr-985481

RESUMEN

The radioactive safety of drinking water has attracted increasing public concern. The newly issued Standards for Drinking Water Quality (GB5749-2022) in China has revised the radiological parameters. This article provides an overview of the main sources, levels of radionuclides in drinking water, and summarized the individual doses criterion and adverse health effects associated with exposure of the public to radionuclides from drinking-water. It analyzes and discusses the relevant revision content of radiological parameters, including the guidance values for screening gross α and gross β, subtracting the contribution of potassium-40 from gross β activity when the gross β activity concentration exceeds the screening level, and the basis for establishing the limit values of reference indices uranium and radium-226. Specific implementation and evaluation suggestions are also proposed.


Asunto(s)
Humanos , China , Agua Potable , Radioisótopos/análisis , Uranio/análisis , Abastecimiento de Agua
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