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1.
Radiat Prot Dosimetry ; 200(11-12): 1121-1126, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016487

RESUMO

The activity concentrations of 238U, 232Th and 40K were found using high-resolution gamma-ray spectrometry on depth profile samples collected from the Kalaburagi districts. This study aims to ascertain the radioactivity Changes concerning the depth profile. With values of 51.64 ± 0.50 Bq kg-1 for 238U, 58.77 ± 0.23 for 232Th and 313.92 ± 3.57 for 40K, respectively, the depth profile samples of Jayanagar in the Kalaburagi region exhibit significant activity concentrations among the measured values. Moreover, estimates of the K/Th and K/U ratios have been made, based on surface-level collected samples, which may have values that differ from the samples under study.


Assuntos
Radioisótopos de Potássio , Monitoramento de Radiação , Espectrometria gama , Tório , Urânio , Índia , Monitoramento de Radiação/métodos , Tório/análise , Urânio/análise , Espectrometria gama/métodos , Radioisótopos de Potássio/análise , Poluentes Radioativos do Solo/análise
2.
Radiat Prot Dosimetry ; 200(11-12): 1132-1137, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016493

RESUMO

KAlpakkam MINI reactor (KAMINI) is a 233U fuelled research reactor has various neutron irradiation locations for experimental purposes. The pit at the south beam end of KAMINI reactor is being extensively utilised for neutron attenuation experiments in prospective shielding materials as well as for neutron radiography. During reactor operation, it will be closed by a movable shield. A vault door is located above the shield and the movable shield is used to attenuate streaming neutrons and gamma-rays during reactor operation. Even with the shield, there exists significant dose because of streaming neutrons and gamma rays. Its variation depends on the power of the reactor. The neutron and gamma dose rates close to the south beam vault door have recently been found to be 275-300 µSv/h and 175-200 µSv/h, respectively, when the reactor is operating at 10 kW. In order to characterise the streaming neutron spectra of vault door place for the first time, measurements are done using the Nested Neutron Spectrometer. Along with the neutron flux, neutron mean energy and ambient dose-equivalent rate are also measured and compared with earlier measurements carried out inside the south beam pit. It is observed that the presence of paraffin shield reduces the neutron average energy from 370 to 178 keV. Apart from energy reduction, 10 kW normalised neutron flux of south beam pit is also attenuated by the shield by 25 000 times and it is found that the neutron spectrum of the measured location is also more thermalized. Neutron reference data of the location are generated.


Assuntos
Raios gama , Nêutrons , Reatores Nucleares , Doses de Radiação , Proteção Radiológica , Proteção Radiológica/métodos , Proteção Radiológica/instrumentação , Monitoramento de Radiação/métodos , Monitoramento de Radiação/instrumentação , Desenho de Equipamento , Análise Espectral/instrumentação , Análise Espectral/métodos , Humanos , Tório/análise , Urânio
3.
Radiat Prot Dosimetry ; 200(11-12): 1127-1131, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016504

RESUMO

Coal based thermal power plants contribute about ~ 72% of the power generation in India. Indian coal is of bituminous type, having a high ash content with 55-60% ash. Due to considerable environmental importance the collected fly ash has become a subject of worldwide interest in recent years. In the present study radon exhalation rate and the activity concentration of 226Ra, 232Th and 40K radionuclides in fly ash samples from Kasimpur Thermal Power Plant, Aligarh, Uttar Pradesh, India have been measured by 'Sealed Can technique' using LR-115 type II detectors and a low-level NaI (Tl)- based gamma-ray spectrometer, respectively. Radon exhalation rate has been found to vary from 57.1 ± 5.3 to 119.4 ± 7.7 mBq m-2 h-1 with an average value of 87.3 ± 5.8 mBq m-2 h-1. Activity concentration of 226Ra ranged from 20.0 ± 8.5 to 30.0 ± 9.7 Bq kg-1 with an average value 23.4 ± 9.0 Bq kg-1, 232Th ranged from 17.0 ± 9.9 to 69.0 ± 13.8 Bq kg-1 with an average value of 46.5 ± 12.1 Bq kg-1 and 40K ranged from 130.0 ± 7.2 to 332.0 ± 11.1 Bq kg-1 with an average value of 177.0 ± 8.1 Bq kg-1.


Assuntos
Poluentes Radioativos do Ar , Cinza de Carvão , Doses de Radiação , Monitoramento de Radiação , Rádio (Elemento) , Radônio , Espectrometria gama , Cinza de Carvão/análise , Radônio/análise , Monitoramento de Radiação/métodos , Poluentes Radioativos do Ar/análise , Índia , Rádio (Elemento)/análise , Espectrometria gama/métodos , Centrais Elétricas , Tório/análise , Radioisótopos de Potássio/análise
4.
Radiat Prot Dosimetry ; 200(11-12): 1041-1046, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016506

RESUMO

Radionuclide activity of the selected radionuclides 238U, 232Th and 40K was measured in surface soil samples collected from 40 villages of the western part of Yadgir district of Karnataka. A 4″ × 4″ NaI (Tl) detector based on a gamma spectrometer is used for the estimation of radionuclides. The major type of soil in this region is sandy and red. The 222Rn activity concentrations in drinking water were determined by the Emanometry method. The 222Rn activity in ground water is found to vary from 1.73 to 155.6 Bql-1. The total annual effective doses because of 222Rn inhalation and ingestion range from 4.72 to 424.84 µSv y-1 with an average value of 108.8 µSv y-1, respectively. Among the sampling stations, Shahapur and Shorapur soil samples show higher activity values than the Kembhavi and Hunasagi sampling stations soil samples.


Assuntos
Água Potável , Radioisótopos de Potássio , Monitoramento de Radiação , Poluentes Radioativos do Solo , Poluentes Radioativos da Água , Índia , Poluentes Radioativos do Solo/análise , Monitoramento de Radiação/métodos , Água Potável/análise , Poluentes Radioativos da Água/análise , Radioisótopos de Potássio/análise , Tório/análise , Urânio/análise , Espectrometria gama , Humanos , Radônio/análise , Radiação de Fundo , Solo/química
5.
Radiat Prot Dosimetry ; 200(11-12): 1059-1063, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016509

RESUMO

Natural radioactivity measurement, radiation monitoring of the region, dose assessment and interpretation of radiological-related parameters are crucial aspects from the public awareness and environmental safety point of view. The ionising radiations (gamma-rays) emitted from radionuclides such as 226Ra, 232Th and 40K present in environmental materials contributes significantly to the external radiation dose received by the public. High-efficiency gamma spectrometry based on a 4″ × 4″ NaI (Tl) detector was employed for estimating activity concentrations of the gamma-emitting radioelements. The spectra from the detector were recorded using a PC-based 1k multichannel analyser system (WinTMCA 32). Each sample spectrum was acquired for a counting period of 60 000 s (16.67 hr). Assuming the daughter products of 226Ra and 232Th in equilibrium, the activity concentration of these radionuclides were estimated by using the prominent gamma photo peaks of daughter products. Using the same technique, dose-related radiological parameters were calculated for all the samples. The activity concentrations of the radionuclides and the dose-related parameters for the samples were found to be comparable with the global literature values. The data generated from our study will contribute to the baseline radiological data of the region.


Assuntos
Radiação de Fundo , Raios gama , Radioisótopos de Potássio , Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Espectrometria gama , Tório , Índia , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Tório/análise , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Doses de Radiação
6.
Radiat Prot Dosimetry ; 200(11-12): 1070-1075, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016513

RESUMO

The natural radioactivity concentration was studied for 40 soil samples of the Churchandpur and Ukhrul districts of Manipur, India, by using gamma-ray spectroscopy. The average radioactivity concentration of 226Ra, 232Th and 40K in Churchandpur was found as 39.9 (range: 30-56), 72.1 (range: 57-93) and 564.1 (range:360-867) Bq kg-1 respectively, whereas, in Ukhrul, average radioactivity for the same was found as 30.3 (range: 16-54), 54.2 (range:24-89) and 637.1(range:103-901) Bq kg-1, respectively. The calculated radioactivity parameters were compared with the world average values. The measured radium equivalent activity (Raeq), absorbed dose rate ($\dot{\mathrm D}$), annual effective outdoor dose(E) and the external hazard index (Hex) were observed as 165 (range: 63.7-234.8) Bq kg-1, 77.6 (36.9-108.0) nGy h-1, 0.11 (0.05-0.13) mSv y-1 and 0.5 (0.1-0.6), respectively. This study aims to provide baseline data for radionuclide present in the Churchandpur and Ukhrul districts of Manipur.


Assuntos
Radiação de Fundo , Radioisótopos de Potássio , Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Tório , Poluentes Radioativos do Solo/análise , Índia , Monitoramento de Radiação/métodos , Tório/análise , Rádio (Elemento)/análise , Radioisótopos de Potássio/análise , Doses de Radiação , Espectrometria gama , Solo/química
7.
Radiat Prot Dosimetry ; 200(10): 938-944, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38855821

RESUMO

An assessment of radioactivity concentration of reinforced cement concrete types of house was conducted in the valley region of Manipur, India. The average radioactivity concentration of 226Ra, 232Th, and 40K of portland cements are 39 (range: 32-52) Bqkg-1, 36 (range: 22-62) Bqkg-1, and 1812 (1254-2424) Bqkg-1; for concrete are 36 (range: 26-45) Bqkg-1, 65 (range: 45-86) Bqkg-1, and 660 (639-681) Bqkg-1; for sand are 45 (30-61) Bqkg-1, 114 (range: 55-212) Bqkg-1, and 1859 (range: 1413-2232) Bqkg-1; and for bricks are 30 (range: 24-37) Bqkg-1, 148 (range:79-184) Bqkg-1, and 1444 (range: 1093-2103) Bqkg-1, respectively. The annual effective dose was observed with an average value of 1.9 (range: 0.9-3.3) mSvy-1. However, gamma index was observed with an average value of 1.1 (range: 0.5-2.0).


Assuntos
Materiais de Construção , Radioisótopos de Potássio , Monitoramento de Radiação , Rádio (Elemento) , Tório , Materiais de Construção/análise , Índia , Monitoramento de Radiação/métodos , Tório/análise , Rádio (Elemento)/análise , Radioisótopos de Potássio/análise , Radiação de Fundo , Humanos , Doses de Radiação
8.
Radiat Prot Dosimetry ; 200(10): 901-918, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38855829

RESUMO

The aim of the study is a thorough investigation of the radioactivity level in soils of the town of Bitola (Macedonia) and its environs. Topsoil samples collected from 58 locations within a 5 × 5 km grid were analysed. Serving as a screening, gross alpha and beta activity measurements were performed using gas-flow proportional counter. Gamma-spectrometric measurements revealed the presence of three natural (40K, 226Ra, 232Th) and one artificial radionuclide (137Cs) in the samples. The activity concentrations of these radionuclides were consistent with the results of similar studies in neighbouring areas. Spatial distribution maps and factor analyses have revealed that the activity concentrations of the natural radionuclides are strongly influenced by geology and have no significant influence from human activities. A correlation of 137Cs activity concentrations with terrain elevation was also observed. The aim of the study is a thorough investigation of the radioactivity level in soils of the town of Bitola (Macedonia) and its environs. Topsoil samples collected from 58 locations within a 5 × 5 km grid were analysed. Serving as a screening, gross alpha and beta activity measurements were performed using gas-flow proportional counter. Gamma-spectrometric measurements revealed the presence of three natural (40K, 226Ra, 232Th) and one artificial radionuclide (137Cs) in the samples. The activity concentrations of these radionuclides were consistent with the results of similar studies in neighbouring areas. Spatial distribution maps and factor analyses have revealed that the activity concentrations of the natural radionuclides are strongly influenced by geology and have no significant influence from human activities. A correlation of 137Cs activity concentrations with terrain elevation was also observed.


Assuntos
Radioisótopos de Césio , Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Espectrometria gama , Poluentes Radioativos do Solo/análise , Monitoramento de Radiação/métodos , Rádio (Elemento)/análise , Radioisótopos de Césio/análise , Radioisótopos de Potássio/análise , Tório/análise , Humanos , Solo/química , Cidades
9.
J Environ Manage ; 365: 121616, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941854

RESUMO

Volcanic eruption is associated with the release of large volumes of pollutants in the environment, which can pose a risk to humans and other living organisms. The elemental and radioisotope composition of ash released during the Shiveluch Volcano eruption in 2023 was analyzed using ICP-MS and low-background gamma spectrometry. The ash consisted of 59% SiO2, 16.7% Al2O3, 5.3% CaO, 4.6 % Na2O, 4.5% Fe2O3, 1.4% K2O, 0.48% TiO2, 0.17% P2O5, 0.15% S, 0.078% MnO and 44 trace elements. Hazard Quotient and Hazard Index were calculated in order to evaluate the potential health risks to children and adults due to exposure to contaminants via inhalation, ingestion, and dermal contact. All values were below the unit, indicating a low probability of non-carcinogenic and cancerogenic risk occurrence in target groups. The average activity concentrations of the natural radionuclides were 350, 12.4 and 4.84 Bq/kg for 40K, 226Ra and 232Th. Radiological indices, including external and internal risk assessment, radium equivalent activity, annual effective dose, gamma index, and excess lifetime cancer risk were calculated to estimate the radiological hazard for the population. The values of all indices were below the recommended safety limits, indicating a low level of hazard for the exposed population.


Assuntos
Metais , Radioisótopos , Erupções Vulcânicas , Humanos , Metais/análise , Radioisótopos/análise , Rádio (Elemento)/análise , Medição de Risco , Tório/análise
10.
Appl Radiat Isot ; 211: 111413, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38944898

RESUMO

The plant acts as an important route for the transfer of radionuclides from the soil to animals, leading to the transfer of radiation to human food products such as beef and milk. Therefore, the level of radioactivity in fodder plays a crucial role in deciding whether cattle may be allowed to graze in a certain area. In this study, the activities of 226Ra, 232Th and 40K were measured via gamma-ray spectrometry on different fodder samples, including napier leaves, rice straw, corn stalks, guinea grass, mixed pasture, palm oil leaves and palm kernel collected from Penang, Malaysia. Theoretical calculations were also conducted to estimate the levels of these radionuclides in caw's products (beef and milk), as well as their potential radiological impact on local consumers. On average, the annual effective dose due to ingestion of radionuclides in milk was 11.39 µSv y-1, whereas in beef it was 5.63 µSv y-1. These values are significantly lower than the worldwide average of 290 µSv y-1. Research confirmed that farmers' usage of the aforementioned feeds did not cause any radiation-related health risks.


Assuntos
Ração Animal , Contaminação Radioativa de Alimentos , Radioisótopos de Potássio , Rádio (Elemento) , Tório , Malásia , Tório/análise , Rádio (Elemento)/análise , Radioisótopos de Potássio/análise , Animais , Contaminação Radioativa de Alimentos/análise , Bovinos , Ração Animal/análise , Leite/química , Humanos , Espectrometria gama , Monitoramento de Radiação/métodos
11.
Appl Radiat Isot ; 211: 111411, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38905969

RESUMO

This study evaluates the radiological risk associated with the consumption of infant powdered milk in Albania. Infant powdered milk is the basic foodstuff for their growth and development in many countries around the world. The activity concentration of radionuclides (40K, 226Ra, 232Th and 137Cs) was measured in fourteen types by using the gamma-ray technique. The results indicated that the activity concentration of 40K, 226Ra and 232Th were detected in all selected samples, whereas 137Cs were not detected in most of them. The activity concentration of 40K, 226Ra and 232Th varies from 92.83 ± 4.32 to 400.53 ± 17.00 Bq kg-1, 0.80 ± 0.15 to 4.91 ± 0.28 Bq kg-1 and 0.19 ± 0.02 to 1.89 ± 0.14 Bq kg-1, respectively. The highest value for 137Cs was found to be 0.36 ± 0.03 Bq kg-1. The average values of Annual Effective Dose (AED) due to consumption of powdered milk were found to be 664.54 ± 31.11 µSv y-1 for infants ≤1 year and 138.53 ± 5.40 µSv y-1 for infants 1-2 years. The values of dose in this study were lower than the recommended limit of 1 mSv y-1 set by WHO/FAO and ICRP for all ages. Therefore, brands of powdered milk are safe, so, these can be normally consumed by infants in Albania.


Assuntos
Radioisótopos de Césio , Contaminação Radioativa de Alimentos , Fórmulas Infantis , Radioisótopos de Potássio , Doses de Radiação , Albânia , Humanos , Radioisótopos de Césio/análise , Lactente , Contaminação Radioativa de Alimentos/análise , Fórmulas Infantis/química , Fórmulas Infantis/análise , Radioisótopos de Potássio/análise , Tório/análise , Rádio (Elemento)/análise , Leite/química , Animais , Monitoramento de Radiação/métodos
12.
Environ Geochem Health ; 46(6): 181, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695964

RESUMO

This study determined natural and artificial radionuclide concentrations to evaluate natural radioactivity and health risk levels of nine travertines in the Yaprakhisar and Balkayasi regions in Turkey. The samples coded B1-M, B2, B5, B7, B8, and B10 represent waste derived from the Yaprakhisar travertines, as well as samples T5-M, T12, and Z1 travertines derived from Balkayasi. The levels of natural and artificial radionuclide concentrations (232Th, 40K, and 137Cs) were measured using a high-purity germanium (HpGe) detector system. The travertine activity ranged from 2.09 to 12.07 Bq kg-1 for 232Th, 4.21 to 13.41 Bq kg-1 for 40K, and 0.42-3.26 Bq kg-1 for 137Cs. The results showed that the activity concentration values for 232Th, 40K, and 137Cs were coherent with the travertine analysis results in the UNSCEAR, 2000; 2008 publications. The values obtained were lower than the average values in the UNSEAR reports. The radiological hazard parameters calculated in this study were absorbed gamma dose rate (D), radium equivalent activity (Raeq), annual gonadal dose equivalent (AGDE), exposure dose (ER), total annual effective dose (AEDEtotal), excess lifetime cancer risk (ELCRtotal), gamma representative level (GRL), internal hazard index (Hin) and external hazard index (Hex).


Assuntos
Radioisótopos de Césio , Radioisótopos de Potássio , Monitoramento de Radiação , Turquia , Monitoramento de Radiação/métodos , Radioisótopos de Potássio/análise , Radioisótopos de Césio/análise , Tório/análise , Poluentes Radioativos do Solo/análise , Radiação de Fundo , Humanos , Medição de Risco
13.
Appl Radiat Isot ; 210: 111355, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38761509

RESUMO

This study calculates dose rate in Gy y-1 for individual dust, soil, and sediment particles that contain significant amounts of alpha-emitting uranium or thorium. When inhaled or ingested, these particles deliver radiation dose to organs where they embed. The presented method uses X-ray microscopy to measure alpha emitting elements in environmental microparticles, followed by calculation of dose rates delivered to the targeted volume of tissues that surround embedded microparticles. The example calculations use a real-world, 89% uranium house dust particle.


Assuntos
Partículas alfa , Doses de Radiação , Tório , Urânio , Urânio/análise , Tório/análise , Humanos , Poeira/análise , Poluentes Radioativos do Solo/análise
14.
Mar Pollut Bull ; 203: 116500, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38762937

RESUMO

The study on natural radionuclides in edible bivalves from the Cochin backwater lagoon, Kerala, employing alpha spectrometry, revealed higher concentrations of 210Po and 210Pb compared to 238U and 232Th. The annual committed effective dose (ACED) for the adult coastal population was calculated at a range of 1494.9 to 5783.4 µSv y-1, with 210Po being the predominant contributor, responsible for about 85 % of the dose. This highlighted significant health risks, underscored by a calculated cumulative mortality and morbidity risk range between 5.23 × 10-3 and 2.02 × 10-2. These findings emphasized the need for further research and the development of regulatory measures to mitigate exposure risks.


Assuntos
Bivalves , Monitoramento de Radiação , Poluentes Radioativos da Água , Animais , Índia , Poluentes Radioativos da Água/análise , Polônio/análise , Tório/análise , Radioisótopos de Chumbo/análise , Humanos
15.
Chemosphere ; 359: 142326, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763398

RESUMO

Accessory minerals in granitic rocks are unlikely significant radionuclide contributions to groundwater due to their remarkable durability. However, accessory minerals incorporating U and Th may suffer structural damages due to the radioactivity and become highly susceptible to alteration. This study investigates geochemistry coupled with textural analysis of the U-Th bearing accessory minerals using a field emission scanning electron microscope and an electron probe micro-analyzer. Altered zircons with numerous open structures related to the radioactive decay show higher contents of U and Th and low analytical totals. Some thorites show high contents of U and non-formula elements due to the hydrothermal alteration in the metamicted thorite. The cerianite including U occurs as micro-veinlet in fracture with trace of Fe and Mn oxides, which indicates secondary phase formation from the decomposed accessory minerals in an oxidizing environment. Some accessory minerals with the high content of U and Th have been found in Mesozoic granite terrain in South Korea, where high concentration levels of radionuclide in groundwater were also reported. The leaching of U may be more likely when the accessory minerals are highly metamicted or altered as found in our samples. The altered zircon and thorite of the study area could be major carriers of radioelement in Mesozoic granitic aquifers where the occurrence of soluble U-minerals has not been reported.


Assuntos
Água Subterrânea , Minerais , Dióxido de Silício , Poluentes Radioativos da Água , Água Subterrânea/química , Minerais/química , Minerais/análise , Poluentes Radioativos da Água/análise , Dióxido de Silício/química , Urânio/análise , Radioisótopos/análise , Monitoramento de Radiação , Tório/análise , Poluentes Radioativos do Solo/análise , Zircônio , Silicatos
16.
Radiat Prot Dosimetry ; 200(8): 715-720, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38689537

RESUMO

This study used gamma ray spectrometry to determine the radiological safety of construction soil sampled randomly from Mbeere North region, Kenya. The mean activity concentration of 232Th, 238U, and 40K was 149.7 ± 2.8 Bqkg-1, 88.3 ± 2.4 Bqkg-1, and 490 ± 35 Bqkg-1, respectively. These averages exceed the world average for all the radionuclides. The radionuclides were non-uniformly distributed, with higher concentrations along the slopes and on the feet of the hills. The mean absorbed dose rate, indoor and outdoor annual effective dose, radium equivalent, external hazard index, and internal hazard index were 157.9 ± 4.4 nGh-1, 0.58 ± 0.02 mSvy-1, 0.39 ± 0.01 mSvy-1, 340.7 ± 9.2 Bqkg-1, 0.92 ± 0.02 and 1.14 ± 0.03, respectively. Among the radiation safety indicators, only the average internal hazard index exceeded slightly the acceptable safe limit. Therefore, soils of Mbeere North region are radiologically safe for use in brick making and construction of human habitats.


Assuntos
Radioisótopos de Potássio , Monitoramento de Radiação , Poluentes Radioativos do Solo , Espectrometria gama , Tório , Quênia , Poluentes Radioativos do Solo/análise , Monitoramento de Radiação/métodos , Tório/análise , Radioisótopos de Potássio/análise , Humanos , Urânio/análise , Doses de Radiação , Raios gama
17.
J Environ Radioact ; 276: 107447, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38749216

RESUMO

Soil is an important source and medium of radionuclides, and the content of radioactivity in soil is crucial for radiological impact evaluation. In this study, twenty soil samples in the high background natural radiation area of Yangjiang, China were collected and analyzed for 226Ra, 232Th, 40K and 137Cs concentrations in order to evaluate the radiological health risk in the area. Results showed that the average activity concentrations of 226Ra, 232Th and 40K are 66 Bq/kg, 109 Bq/kg and 211 Bq/kg, respectively. The calculated radiological parameters of radium equivalent activity (Raeq), absorbed dose rate (D), annual effective dose equivalent (AEDE), internal and external hazard indices (Hin and Hex) show a large variation at different sampling sites. Additionally, the elemental oxidation composition and 40K/K mass ratio in the soil were analyzed to further augment the background information of the high background radiation area in Yangjiang.


Assuntos
Radiação de Fundo , Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Solo , Tório , Poluentes Radioativos do Solo/análise , China , Solo/química , Rádio (Elemento)/análise , Tório/análise , Radioisótopos de Potássio/análise , Radioisótopos de Césio/análise , Oxirredução
18.
Mar Pollut Bull ; 202: 116349, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604081

RESUMO

Coastal Mangroves are facing growing threats due to the harmful consequences of human activities. This first-ever detailed study of natural radioactivity in soil samples collected from seven tourist destinations within the Sundarbans, the world's largest mangrove forest, was conducted using HPGe gamma-ray spectrometry. Although the activity levels of 226Ra (11 ± 1-44 ± 4 Bq/kg) and 232Th (13 ± 1-68 ± 6 Bq/kg) generally align with global averages, the concentration of 40K (250 ± 20-630 ± 55 Bq/kg) was observed to surpass the worldwide average primarily due to factors like salinity intrusion, fertilizer application, agricultural runoff, which suggests the potential existence of potassium-rich mineral resources near the study sites. The assessment of the hazard parameters indicates that the majority of these parameters are within the recommended limits. The soil samples do not pose a significant radiological risk to the nearby population. The results of this study can establish important radiological baseline data before the Rooppur Nuclear Power Plant begins operating in Bangladesh.


Assuntos
Monitoramento de Radiação , Áreas Alagadas , Poluentes Radioativos do Solo/análise , Rádio (Elemento)/análise , Tório/análise , Espectrometria gama , Solo/química , Bangladesh , Radioisótopos de Potássio/análise , Florestas
19.
Appl Radiat Isot ; 207: 111266, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461629

RESUMO

Brazil is the fourth largest cement consumer in the world and the largest producer in Latin America, around 1.3% of global production. The main inputs in the manufacture of cement are limestone and clay. Few studies have been carried out in the country on the risk of these materials used in civil construction. Therefore, the objective of this present work is to evaluate the radiological danger that they can present to society. Gamma spectrometry analysis on 16 samples of different brands of cement used as construction material in Rio de Janeiro (Brazil) was performed in this study, using an HPGe detector and the Genie 2000 data acquisition software. Samples were set to count for an accumulation time of 14,400 s (4 h) and all measurements were corrected to eliminate background and backscattering. Activity concentrations are determined for 226Ra was from (41.2 ± 1.6 to 174.9 ± 3.9) Bq kg-1, 232Th was from (15.7 ± 0.5 to 43.1 ± 0.7) Bq kg-1 and 40K was from (82.6 ± 7.2 to 254 ± 17) Bq kg-1. To assess radiological health risks: mean values of Radium Activity Equivalent 150.0 ± 3.4 Bq kg-1, Annual Gonadal Dose Equivalent 468 ± 11 µSv year-1 and Lifetime Excess Cancer Risk (ELCR) 2.42 ± 0.06 were calculated. Total Absorbed Dose Rates ranged from 72.2 ± 1.7 to 225.1 ± 5.2 nGy h-1. The damage to collective health was also estimated from the annual effective dose rates with an estimated total cost of damage to health of US$ 130 million. Values are generally within global limits reported by UNSCEAR.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Radioisótopos de Potássio/análise , Tório/análise , Monitoramento de Radiação/métodos , Brasil , Materiais de Construção/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Espectrometria gama
20.
Artigo em Inglês | MEDLINE | ID: mdl-38541314

RESUMO

This article reports the results of an investigation into the activity concentration of natural radionuclides in raw building materials for underground parking lots, together with the assessment of the radiation hazard for the public related to exposure to ionizing radiations. To this purpose, high-purity germanium (HPGe) γ-ray spectrometry was employed in order to quantify the average specific activity of 226Ra, 232Th, and 40K natural radioisotopes. With the aim to assess any possible radiological health risk for the population, the absorbed γ-dose rate (D), the annual effective dose equivalent outdoor (AEDEout) and indoor (AEDEin), the activity concentration index (I), and the alpha index (Iα) were also estimated, resulting in values that were lower than the maximum recommended ones for humans. Finally, the extent of the correlations existing between the observed radioactivity and radiological parameters and of these parameters with the analyzed samples was quantified through statistical analyses, including Pearson's correlation, a principal component analysis (PCA), and a hierarchical cluster analysis (HCA). As a result, three clusters of the investigated samples were recognized based on their chemical composition and mineralogical nature. Noteworthily, this paper covers a certain gap in science since its topic does not appear in literature in this form. Thus, the authors underline the importance of this work to global knowledge in the environmental research and public health fields.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Humanos , Monitoramento de Radiação/métodos , Radioisótopos/análise , Saúde Radiológica , Espectrometria gama , Materiais de Construção/análise , Tório/análise , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise
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