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Veerasamy N, Murugan R, Kasar S, Inoue K, Kavasi N, Balakrishnan S, Arae H, Fukushi M, Sahoo SK. Geochemical characterization of monazite sands based on rare earth elements, thorium and uranium from a natural high background radiation area in Tamil Nadu, India. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2021; 232:106565. [PMID: 33714078 DOI: 10.1016/j.jenvrad.2021.106565] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 06/12/2023]
Abstract
The Kanyakumari coastal area in the southernmost part of Tamil Nadu, India is a well-known natural high background radiation area due to the abundance of monazite in beach placer deposits. In the present study, the concentrations of major oxides, rare earth elements (REEs), Th and U were measured to understand geochemical characteristics of these monazite sands. Based on the ambient dose rate, 23 locations covering an area of about 60 km along the coast were selected for sample collection. The concentrations of U and Th ranged from 1.1 to 737.8 μg g-1 and 25.2-12250.6 μg g-1, respectively. The Th/U ratio ranged from 2.2 to 61.6, which clearly indicated that Th was the dominant contributing radionuclide to the enhanced natural radioactivity in this coastal region. The chondrite-normalized REEs pattern of the placer deposits showed enrichment in light REEs and depletion in heavy REEs with a negative Eu anomaly that indicated the monazite sands were derived from granite, charnockite, and granitoid rocks from the Nagercoil and the Trivandrum Blocks of the Southern Granulite Terrain.
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Affiliation(s)
- N Veerasamy
- Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, 116-8551, Japan; Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - R Murugan
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - S Kasar
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - K Inoue
- Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - N Kavasi
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - S Balakrishnan
- Department of Earth Sciences, Pondicherry University, R Venkat Raman Nagar, Kalapet, Puducherry, 605014, India
| | - H Arae
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - M Fukushi
- Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - S K Sahoo
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
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Veerasamy N, Sahoo SK, Inoue K, Arae H, Fukushi M. Geochemical behavior of uranium and thorium in sand and sandy soil samples from a natural high background radiation area of the Odisha coast, India. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:31339-31349. [PMID: 32483717 DOI: 10.1007/s11356-020-09370-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
Owing to their natural radioactivity, uranium (U) and thorium (Th) play significant roles in environmental sciences for monitoring radiation dose and in geological sciences for understanding sedimentary processes. The Odisha coastal area, in eastern India, is a well-known high background radiation area that is rich in monazites and rutile. This area was selected to study geochemical characteristics of U and Th in sand and sandy soil samples. The concentrations of U and Th were measured using inductively coupled plasma mass spectrometry (ICP-MS). The median, geometric mean, and standard deviation for U were determined to be 6, 4.5, and 2.5 μg/g and for Th were 186, 123.3, and 3.1 μg/g, respectively. Major element concentrations were evaluated using X-ray fluorescence spectroscopy to get the mineralogical composition and state of chemical weathering. The ratios of Th/U and Th/K varied from 4 to 37 and from 13 to 1058, respectively. These results clearly indicate that the samples from the coastal region were formed in an oxidizing and intense chemical weathering terrestrial environment with an enrichment of radiogenic heavy minerals (monazites and zircon) and clay mineral association. Since the majority of the samples have undergone moderate to intense weathering in the oxidizing environment, U is leached from the soil and sand matrix. Eventually, Th resides in the matrix and becomes a major source for radiation exposure in the environment. The high ratios of Th/U, along with the strong positive correlation between Th and P2O5, evidence the enrichment of the Th-bearing radioactive mineral, monazite, in these samples.
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Affiliation(s)
- Nimelan Veerasamy
- Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, 116-8551, Japan
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Sarata Kumar Sahoo
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
| | - Kazumasa Inoue
- Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Hideki Arae
- Environmental Radionuclides Research Group, National Institutes for Quantum and Radiological Sciences and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Masahiro Fukushi
- Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, 116-8551, Japan
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Inoue K, Sahoo SK, Veerasamy N, Kasahara S, Fukushi M. Distribution patterns of gamma radiation dose rate in the high background radiation area of Odisha, India. J Radioanal Nucl Chem 2020. [DOI: 10.1007/s10967-020-07176-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Cid AS, Anjos RM, Zamboni CB, Cardoso R, Muniz M, Corona A, Valladares DL, Kovacs L, Macario K, Perea D, Goso C, Velasco H. Na, K, Ca, Mg, and U-series in fossil bone and the proposal of a radial diffusion-adsorption model of uranium uptake. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2014; 136:131-139. [PMID: 24953228 DOI: 10.1016/j.jenvrad.2014.05.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 05/20/2014] [Accepted: 05/23/2014] [Indexed: 06/03/2023]
Abstract
Fossil bones are often the only materials available for chronological reconstruction of important archeological sites. However, since bone is an open system for uranium, it cannot be dated directly and therefore it is necessary to develop models for the U uptake. Hence, a radial diffusion-adsorption (RDA) model is described. Unlike the classic diffusion-adsorption (D-A) model, RDA uses a cylindrical geometry to describe the U uptake in fossil bones. The model was applied across a transverse section of a tibia of an extinct megamammal Macrauchenia patachonica from the La Paz Local Fauna, Montevideo State, Uruguay. Measurements of spatial distribution of Na, K, Ca, and Mg were also performed by neutron activation analysis (NAA). Gamma-ray spectrometric U-series dating was applied to determine the age of the bone sample. From U concentration profile, it was possible to observe the occurrence of a relatively slow and continuous uranium uptake under constant conditions that had not yet reached equilibrium, since the uranium distribution is a ∪-shaped closed-system. Predictions of the RDA model were obtained for a specific geochemical scenario, indicating that the effective diffusion coefficient D/R in this fossil bone is (2.4 ± 0.6)10(-12) cm(2)s(-1). Mean values of Na, K, Ca, and Mg contents along the radial line of the fossil tibia are consistent with the expected behavior for spatial distributions of these mineral elements across a modern bone section. This result indicates that the fossil tibia may have its mineral structure preserved.
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Affiliation(s)
- A S Cid
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - R M Anjos
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil.
| | - C B Zamboni
- Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN), Centro do Reator de Pesquisa (CRPq), Av. Lineu Prestes 2242 - Cidade Universitária, 05508-000, São Paulo, SP, Brazil
| | - R Cardoso
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - M Muniz
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - A Corona
- Departamento de Evolución de Cuencas, Facultad de Ciencias, UDELAR, Iguá 4225, Montevideo 11400, Uruguay
| | - D L Valladares
- GEA - Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, CCT-San Luis CONICET, Ej. de los Andes 950, D5700HHW, San Luis, Argentina
| | - L Kovacs
- Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN), Centro do Reator de Pesquisa (CRPq), Av. Lineu Prestes 2242 - Cidade Universitária, 05508-000, São Paulo, SP, Brazil
| | - K Macario
- LARA - Laboratório de Radioecologia e Alterações Ambientais, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, S/N, Gragoatá, 24210-346, Niterói, RJ, Brazil
| | - D Perea
- Departamento de Evolución de Cuencas, Facultad de Ciencias, UDELAR, Iguá 4225, Montevideo 11400, Uruguay
| | - C Goso
- Departamento de Evolución de Cuencas, Facultad de Ciencias, UDELAR, Iguá 4225, Montevideo 11400, Uruguay
| | - H Velasco
- GEA - Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, CCT-San Luis CONICET, Ej. de los Andes 950, D5700HHW, San Luis, Argentina
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Valladares DL, da Silva AAR, Lacerda T, Anjos RM, Rizzotto M, Velasco H, de Rosas JP, Tognelli G, Yoshimura EM, Ayub JJ. Using (222)Rn as a tracer of geodynamical processes in underground environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 468-469:12-18. [PMID: 24012891 DOI: 10.1016/j.scitotenv.2013.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 07/19/2013] [Accepted: 08/03/2013] [Indexed: 06/02/2023]
Abstract
Radon levels in two old mines in San Luis, Argentina, were measured and analyzed, with the aim to assess the potential use of this radioactive noble gas as a tracer of geological processes in underground environments. La Carolina gold mine and Los Cóndores tungsten mine are today used as tourism mines. CR-39 nuclear track detectors were used for this purpose. Measurements were performed during both winter and summer seasons. The findings show that in these environments, significant radon concentrations are subject to large seasonal fluctuations, due to the strong dependence on natural ventilation with the outside temperature variations. For both mines, higher concentration values of (222)Rn were observed in summer than in winter; with an extreme ratio of 2.5 times between summer and winter seasons for Los Cóndores mine. The pattern of radon transport inside La Carolina mine revealed, contrary to what was believed, that this mine behaves as a system with two entrances located at different levels. However, this feature can only be observed in the winter season, when there is a marked difference between the inside and outside temperatures of the mine. In the case of Los Cóndores mine, the radon concentration pattern distribution is principally established by air current due to chimney-effect in summer and winter seasons. In both cases, the analyses of radon pattern distribution appear as a good method to trace air currents, and then localize unknown ducts, fissures or secondary tunnels in subterranean environments.
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Affiliation(s)
- D L Valladares
- GEA, Instituto de Matemática Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Científicas y Técnicas, Ej. de los Andes 950, D5700HHW San Luis, Argentina
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Abd El Wahab M, El Nahas HA. Radionuclides measurements and mineralogical studies on beach sands, East Rosetta Estuary, Egypt. CHINESE JOURNAL OF GEOCHEMISTRY 2013; 32:146-156. [DOI: 10.1007/s11631-013-0617-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Anjos RM, Juri Ayub J, Cid AS, Cardoso R, Lacerda T. External gamma-ray dose rate and radon concentration in indoor environments covered with Brazilian granites. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2011; 102:1055-1061. [PMID: 21729819 DOI: 10.1016/j.jenvrad.2011.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Revised: 05/30/2011] [Accepted: 06/01/2011] [Indexed: 05/31/2023]
Abstract
Health hazard from natural radioactivity in Brazilian granites, covering the walls and floor in a typical dwelling room, was assessed by indirect methods to predict external gamma-ray dose rates and radon concentrations. The gamma-ray dose rate was estimated by a Monte Carlo simulation method and validated by in-situ measurements with a NaI spectrometer. Activity concentrations of (232)Th, (226)Ra, and (40)K in an extensive selection of Brazilian commercial granite samples measured by using gamma-ray spectrometry were found to be 4.5-450 Bq kg(-1), 4.9-160 Bq kg(-1) and 190-2029 Bq kg(-1), respectively. The maximum external gamma-ray dose rate from floor and walls covered with the Brazilian granites in the typical dwelling room (5.0 m × 4.0 m area, 2.8 m height) was found to be 120 nGy h(-1), which is comparable with the average worldwide exposure to external terrestrial radiation of 80 nGy h(-1) due to natural sources, proposed by United Nations Scientific Committee on the Effects of Atomic Radiation. Radon concentrations in the room were also estimated by a simple mass balance equation and exhalation rates calculated from the measured values of (226)Ra concentrations and the material properties. The results showed that the radon concentration in the room ventilated adequately (0.5 h(-1)) will be lower than 100 Bq m(-3), value recommended as a reference level by the World Health Organization.
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Affiliation(s)
- R M Anjos
- LARA - Laboratório de Radioecologia, Instituto de Física, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/no, Gragoatá, 24210-340 Niterói, RJ, Brazil.
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Carvalho C, Anjos RM, Veiga R, Macario K. Application of radiometric analysis in the study of provenance and transport processes of Brazilian coastal sediments. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2011; 102:185-192. [PMID: 21147506 DOI: 10.1016/j.jenvrad.2010.11.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Revised: 11/04/2010] [Accepted: 11/17/2010] [Indexed: 05/30/2023]
Abstract
Natural gamma radiation of beach sand deposits was measured along the south coast of Rio de Janeiro State, Brazil, with the aim of studying the provenance and transport processes of sediments in this area. Concentrations of thorium, uranium and potassium were evaluated using γ-ray spectrometry and a behavioral study of eTh/eU and eTh/K cross plots was performed, reflecting the mineralogical properties of beach sands, as well as their history of transport and sorting processes. The results show that such technique can be efficiently used to map heavy mineral distributions and to distinguish the different origins of coastal sediments disclosing the influence of nearby rivers.
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Affiliation(s)
- C Carvalho
- Laboratório de Radioecologia (LARA), Instituto de Física, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoatá, Niterói, RJ, Brazil
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Estellita L, Santos A, Anjos R, Yoshimura E, Velasco H, da Silva A, Aguiar J. Analysis and risk estimates to workers of Brazilian granitic industries and sandblasters exposed to respirable crystalline silica and natural radionuclides. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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