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Tang L, Zhao X, Zhang M, Huang Z, Hou X. Quantitative estimation of dust transport in the desert region of northwest China by plutonium isotopes. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2024; 275:107427. [PMID: 38581980 DOI: 10.1016/j.jenvrad.2024.107427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/22/2024] [Accepted: 03/22/2024] [Indexed: 04/08/2024]
Abstract
Dust is an important source of atmospheric pollution, and quantitative estimation of desert dust transport is crucial for air pollution control. In this study, five typical sandy soil profiles in the Tengger Desert were collected and analyzed for 239,240Pu concentration and 240Pu/239Pu atomic ratios in order to identify the source of 239,240Pu in this area and explore the sedimentary characteristics of dust in different profiles. The results revealed that the concentrations of 239,240Pu in the soil profiles were between 0.002 and 0.443 mBq/g with an exception of the deep layer soil at one site. The measured atomic ratios of 240Pu/239Pu are at the global atmospheric fallout level with a mean of 0.184 ± 0.020, indicating that global fallout is the dominant source of plutonium in this region. The total inventories of 239,240Pu in the reference sites in this area were estimated to be 39.2-44.6 Bq/m2, this is in agreement with the value from the global fallout of atmospheric nuclear weapon tests at the similar latitude (30-40 °N: 42 Bq/m2). The estimated erosion rate in the erosion profile utilizing soil erosion intensity mode is 2491 t/km2/yr and the soil erosion depth is 9.86 cm, While, the stacking rate of the accumulation profile is 1383 t/km2/yr, and the depth of accumulation is estimated to be 5.48 cm. The difference between the erosion and accumulation profiles indicated that approximately 1107 t/km2/yr of dust was exported from the Gobi landform area of the Tengger Desert, which might be transported long distance in the downwind direction.
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Affiliation(s)
- Lu Tang
- Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Xue Zhao
- State Key Laboratory of Loess and Quaternary Geology, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an, 710061, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Mengting Zhang
- Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Zhao Huang
- State Key Laboratory of Loess and Quaternary Geology, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an, 710061, China
| | - Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an, 710061, China.
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2
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Guan Y, Jing Q, Wang S, Wang H, Chen W, Hua Y, Guo Z, Cui L, Huang C, Wang L, Kuang P, He X, Liu Z. Radioactivity research in mosses from typical Karst Regions in Leye Tiankeng, Southern China. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 261:107145. [PMID: 36870165 DOI: 10.1016/j.jenvrad.2023.107145] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 11/13/2022] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
Radionuclides in environmental ecosystems have ecotoxicity and health impact on human and environment, so radioactive contamination has always been one of the global concerns. This study mainly focused on the radioactivity of mosses collected from the Leye Tiankeng Group in Guangxi. The activities of 239+240Pu measured by SF-ICP-MS and 137Cs measured by HPGe in moss and soil samples are as follows: 0-2.29 Bq/kg in mosses and 1.5-11.9 Bq/kg in soils for 137Cs, and 0.025-0.25Bq/kg in mosses and 0.07-0.51Bq/kg in soils for 239+240Pu. The range of 240Pu/239Pu atom ratios (0.201 in mosses and 0.184 in soils) and 239+240Pu/137Cs activity ratios (0.128 in mosses and 0.044 in soils) indicated that the 137Cs and 239+240Pu in study area were mainly contributed by global fallout. 137Cs and 239+240Pu showed similar distribution in soils. However, their behaviors in mosses were quite different due to the differences in the growth environment of mosses. The transfer factors of 137Cs and 239+240Pu from soil to moss varied in different growth stages and specific environments. A weak positive correlation among 137Cs, 239+240Pu in mosses and soil-derived radionuclides suggested that resettlement was predominant here. The negative correlation between 7Be, 210Pb and soil-derived radionuclides indicated that 7Be and 210Pb came from atmospheric components, while the weak correlation between them suggested that their specific sources were different. The Cu and Ni were moderately enriched in mosses here due to the use of agricultural fertilizers, At the same time, Zn was at a high level in the Lilang area, where transportation was more developed.
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Affiliation(s)
- Yongjing Guan
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Qiaoyan Jing
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China; State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Centre of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China
| | - Shenzhen Wang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China; State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Centre of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China
| | - Huijuan Wang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Wu Chen
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Yuxin Hua
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Zichen Guo
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Liangjia Cui
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Chunping Huang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China; State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Centre of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China
| | - Liang Wang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Pan Kuang
- Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Xianwen He
- Radiation-Environment Management and Monitoring Station of Guangxi Zhuang Autonomous Region, Guangxi, Nanning, 530222, China
| | - Zhiyong Liu
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Centre of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China.
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Zhang W, Hou X, Dang H, Chen N, Zhang H. Distribution and migration of 239,240Pu in soil profiles in North China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159471. [PMID: 36265634 DOI: 10.1016/j.scitotenv.2022.159471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 10/11/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
The source, vertical distribution and migration behavior of plutonium in five soil profiles (from forest, grassland and desert areas) in northern China were investigated. The average 240Pu/239Pu atomic ratio of 0.184 ± 0.022 observed in these samples is in good agreement with the reported value of global fallout, suggesting that the global fallout is the major source of plutonium in northern China. The 239,240Pu inventories in five soil profiles ranges from 43.3 Bq/m2 to 175 Bq/m2, lying in the reported range for global fallout in the similar latitude band. The effective convection velocity (0.04-0.16 cm/y) and effective dispersion coefficient (0.13-0.41cm2/y) of plutonium in different soil profiles derived using the CDE model varies significantly, attributed to multi-factors including location, topography, climate and soil types. The results showed that the migration of plutonium in grassland soil is significantly slow compared to other type of soil, especially desert soil.
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Affiliation(s)
- Weichao Zhang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Northwest Institute of Nuclear Technology, Xi'an 710024, China
| | - Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Technical University of Denmark, Department of Environmental and Resource Engineering, Risø Campus, DK-4000 Roskilde, Denmark.
| | - Haijun Dang
- Northwest Institute of Nuclear Technology, Xi'an 710024, China
| | - Ning Chen
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Haitao Zhang
- Northwest Institute of Nuclear Technology, Xi'an 710024, China
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Feng D, Yang F, Wang X, Zhou X, Liu Z, Liao H. Distribution of plutonium isotopes in soils between two nuclear test sites: Semipalatinsk and Lop Nor. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 242:106792. [PMID: 34929510 DOI: 10.1016/j.jenvrad.2021.106792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
Plutonium (Pu) has attracted attention as an environmental tracer due to its radiotoxicity and the possibility of sources linked with nuclear accidents in recent years. Plutonium isotopes (239,240Pu) were detected at trace levels in soils collected from the Xinjiang region located between the Semipalatinsk nuclear test site and China's Lop Nor nuclear test site. Little is known regarding the spatial variation of 239,240Pu in soils from this region. This study reports the use of Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICP-MS) methods to distinguish between Pu isotopes derived from global fallout and nuclear weapon tests. We found that the 239,240Pu activity concentrations ranged from 0.035 to 1.338 mBq/g; the 240Pu/239Pu atomic ratios were 0.157-0.223 with a weighted average of 0.180 ± 0.002, corresponding with the expected average global fallout ratio of 0.180 ± 0.014. This indicated that global fallout is the major source of Pu in the study region. The 239,240Pu inventories in these soils ranged from 23.67 to 222.7 Bq/m2, corresponding with those from other areas in China and other countries within the latitude range. Our Pu isotope data was supplemented with other published Pu data for soils collected in the vicinity of the Semipalatinsk nuclear test site and Lop Nor nuclear test site. Results indicate that 239,240Pu inventories and 240Pu/239Pu atomic ratios in soils exhibit large variations with distance from the Semipalatinsk nuclear test site. High deposition and accumulation of Pu, and low 240Pu/239Pu ratios were observed in close-in fallout and downwind regions of the Semipalatinsk nuclear test site and China's Lop Nor nuclear test site.
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Affiliation(s)
- Dongxia Feng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Fang Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Xihuang Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Xingxuan Zhou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Zhiyong Liu
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Centre of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, 215123, China.
| | - Haiqing Liao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
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5
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Zhang W, Hou X, Zhang H, Wang Y, Dang H, Xing S, Chen N. Level, distribution and sources of plutonium in the northeast and north China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117967. [PMID: 34426197 DOI: 10.1016/j.envpol.2021.117967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 06/04/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
Concentrations of 239Pu and 240Pu in 163 surface soil samples and five soil cores collected from the northeast and north China were analyzed using the radiochemical separation combined with inductively coupled plasma mass spectrometry measurement. The average 240Pu/239Pu atomic ratios (0.185 ± 0.018) for all surface soil samples indicated that the global fallout is the major source of plutonium in the studied region. The 239,240Pu concentrations of the surface soil ranged from 0.002 mBq/g to 4.82 mBq/g, lying in the range of the reported results in the areas with similar latitude, except for a few samples. The distribution of 239,240Pu in this region is controlled by the deposition of plutonium in the atmosphere and its preservation in the soil, which were affects by multi-factors such as topography, climate, utilization of the land and vegetation coverage. The analytical results could be used as the baseline data for the assessment of the impact of nuclear activities in the past and the future.
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Affiliation(s)
- Weichao Zhang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Northwest Institute of Nuclear Technology, Xi'an, 710024, China
| | - Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Technical University of Denmark, Department of Environmental Engineering, Risø Campus, 4000, Roskilde, Denmark; CAS Center of Excellence in Quaternary Science and Global Change, Xi'an, 710061, China; Open Studio for Oceanic-Continental Climate and Environment Changes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266061, China.
| | - Haitao Zhang
- Northwest Institute of Nuclear Technology, Xi'an, 710024, China
| | - Yanyun Wang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Haijun Dang
- Northwest Institute of Nuclear Technology, Xi'an, 710024, China
| | - Shan Xing
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Ning Chen
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
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6
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Dang H, Yi X, Zhang Z, Zhang H, Lin J, Zhang W, Zhai S, Zhang J, Bai T, Zhang X, Liang J, Wang W. The level, distribution and source of artificial radionuclides in surface soil from Inner Mongolia, China. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2021; 233:106614. [PMID: 33901800 DOI: 10.1016/j.jenvrad.2021.106614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 03/29/2021] [Accepted: 04/04/2021] [Indexed: 06/12/2023]
Abstract
Mid- and long-half-life artificial radioisotopes in the earth's surface environment are of great concern to the environmental radiation risk assessment. As nuclear fuel and fission products, 239Pu, 240Pu, 241Am, 90Sr and 137Cs in soils from Inner Mongolia of China were analyzed with a modified systematic separation procedure combined with ICP-MS and LSC measurements, to study the level, distribution and source of artificial radionuclides in the region. The radioactivity and inventory of 137Cs (0.26-28.3 Bq/kg, 0.5-5.4 kBq/m2), 239+240Pu (0.05-1.26 Bq/kg, 20-229 Bq/m2), 241Am (0.036-0.35 Bq/kg, 11-81 Bq/m2) and 90Sr (1.2-7.6 Bq/kg, 0.39-1.7 kBq/m2) all lie in the range of the global fallout. Vertical distributions of these radionuclides were examined for two soil core samples SC14025 and SC14038, and great differences were observed between these two sample locations. For SC14025 where little human disturbance to soil occurred, both 137Cs and 239+240Pu have a subsurface activity maximum followed by an exponential decay. Fittings base on CDE model gives a small downward migration velocity of about 0.097 cm/y for both Pu and 137Cs. Source identification for SC14025 and SC14038 soil cores with 240Pu/239Pu (average of 0.180 ± 0.017 and 0.164 ± 0.035, respectively), 137Cs/239+240Pu (average of 25.3 ± 0.6 and 25.6 ± 3.0, respectively) and 241Am/239+240Pu (average of 0.56 ± 0.08 and 0.60 ± 0.09, respectively) ratios consistently indicated that anthropogenic radionuclides in Xilingol region are mostly from the global fallout of atmospheric nuclear weapons tests in the last century. According to the geographical distribution of the radioactivity level, the high radioactivity level in the east of Inner Mongolia probably results from enhanced deposition by the blocking of the Great Khingan Range.
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Affiliation(s)
- Haijun Dang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Xiaowei Yi
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Zilu Zhang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Haitao Zhang
- Northwest Institute of Nuclear Technology, Xian, 710024, China.
| | - Jianfeng Lin
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Weichao Zhang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Shaojing Zhai
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Jiamei Zhang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Tao Bai
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Xiaolin Zhang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Jianfeng Liang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
| | - Wei Wang
- Northwest Institute of Nuclear Technology, Xian, 710024, China
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Zhao X, Qiao J, Hou X. Plutonium isotopes in Northern Xinjiang, China: Level, distribution, sources and their contributions. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 265:114929. [PMID: 32540598 DOI: 10.1016/j.envpol.2020.114929] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/31/2020] [Accepted: 05/31/2020] [Indexed: 06/11/2023]
Abstract
Plutonium in the environment has drawn significant attentions due to its radiotoxicity in high concentration and source term linked with nuclear accidents and contaminations. The isotopic ratio of plutonium is source dependent and can be used as a fingerprint to discriminate the sources of radioactive contaminant. 239Pu, 240Pu and 137Cs in surface soil and soil cores collected from Northern Xinjiang were determined in this work. The concentrations of 239,240Pu and 137Cs are in the range of 0.06-1.20 Bq kg-1, and <1.0-31.4 Bq kg-1 (decay corrected to Sep. 2017), respectively, falling in the ranges of global fallout in this latitude zone. The 240Pu/239Pu atomic ratios of 0.118-0.209 and 239,240Pu/137Cs activity ratios of 0.039-0.215 were measured. Among the investigated sites, distinctly lower 240Pu/239Pu atomic ratios of 0.118-0.133 and higher 239,240Pu/137Cs activity ratios of 0.065-0.215 compared to the global fallout values were observed in the northwest part, indicating a significant contribution from other source besides the global fallout. This extra source is mainly attributed to the releases of atmospheric nuclear weapons testing at Semipalatinsk Nuclear Test Site, which was transported by the west and northwest wind through the river valley among mountains in this region. This contribution is estimated to account for 28-43% of the global fallout in the northwest part of Northern Xinjiang. The contribution from the Chinese atmospheric nuclear weapons testing to this region is negligible due to the lack of appropriate wind direction to transport the radioactive releases to this region.
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Affiliation(s)
- Xue Zhao
- Technical University of Denmark, Department of Environmental Engineering, Risø Campus, Roskilde, 4000, Denmark; State Key Laboratory of Loess and Quaternary Geology, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an, 710061, PR China
| | - Jixin Qiao
- Technical University of Denmark, Department of Environmental Engineering, Risø Campus, Roskilde, 4000, Denmark
| | - Xiaolin Hou
- Technical University of Denmark, Department of Environmental Engineering, Risø Campus, Roskilde, 4000, Denmark; State Key Laboratory of Loess and Quaternary Geology, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an, 710061, PR China; CAS center of Excellence in Quaternary Science and Global Change, Xi'an, 710061, PR China; Open Studio for Oceanic-Continental Climate and Environment Changes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266100, PR China.
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240Pu/ 239Pu and 242Pu/ 239Pu atom ratios of Japanese monthly atmospheric deposition samples during 1963-1966. Sci Rep 2019; 9:8105. [PMID: 31147582 PMCID: PMC6543033 DOI: 10.1038/s41598-019-44352-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/14/2019] [Indexed: 11/29/2022] Open
Abstract
Global fallout plutonium isotopic ratios from the 1960s are important for the use of Pu as environmental tracers. We measured the 240Pu/239Pu and 242Pu/239Pu atomic ratios of monthly atmospheric deposition samples collected in Tokyo and Akita, Japan during March 1963 to May 1966. To our knowledge, our results represent the first data measured for actual atmospheric deposition samples collected continuously during the 1960s. Both atomic ratios increased rapidly from March 1963 to June 1963, followed by a gradual increase until September 1963. Then, both ratios declined with a half-life of approximately 5.6 months. The observed temporal changes of the ratios were likely caused by the upper-stratospheric input of nuclear debris from high-yield atmospheric nuclear weapon testing during 1961–62, followed by its downward transport to the troposphere.
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Xing S, Zhang W, Qiao J, Hou X. Determination of ultra-low level plutonium isotopes ( 239Pu, 240Pu) in environmental samples with high uranium. Talanta 2018; 187:357-364. [PMID: 29853059 DOI: 10.1016/j.talanta.2018.05.051] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/09/2018] [Accepted: 05/13/2018] [Indexed: 11/18/2022]
Abstract
In order to measure trace plutonium and its isotopes ratio (240Pu/239Pu) in environmental samples with a high uranium, an analytical method was developed using radiochemical separation for separation of plutonium from matrix and interfering elements including most of uranium and ICP-MS for measurement of plutonium isotopes. A novel measurement method was established for extensively removing the isobaric interference from uranium (238U1H and 238UH2+) and tailing of 238U, but significantly improving the measurement sensitivity of plutonium isotopes by employing NH3/He as collision/reaction cell gases and MS/MS system in the triple quadrupole ICP-MS instrument. The results show that removal efficiency of uranium interference was improved by more than 15 times, and the sensitivity of plutonium isotopes was increased by a factor of more than 3 compared to the conventional ICP-MS. The mechanism on the effective suppress of 238U interference for 239Pu measurement using NH3-He reaction gases was explored to be the formation of UNH+ and UNH2+ in the reactions of UH+ and U+ with NH3, while no reaction between NH3 and Pu+. The detection limits of this method were estimated to be 0.55 fg mL-1 for 239Pu, 0.09 fg mL-1 for 240Pu. The analytical precision and accuracy of the method for Pu isotopes concentration and 240Pu/239Pu atomic ratio were evaluated by analysis of sediment reference materials (IAEA-385 and IAEA-412) with different levels of plutonium and uranium. The developed method were successfully applied to determine 239Pu and 240Pu concentrations and 240Pu/239Pu atomic ratios in soil samples collected in coastal areas of eastern China.
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Affiliation(s)
- Shan Xing
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China; China Institute of Radiation Protection, Taiyuan, China
| | - Weichao Zhang
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
| | - Jixin Qiao
- Technical University of Denmark, Center for Nuclear Technologies, Risø Campus, Roskilde, Denmark
| | - Xiaolin Hou
- State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China; Technical University of Denmark, Center for Nuclear Technologies, Risø Campus, Roskilde, Denmark.
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Kakimov A, Yessimbekov Z, Kakimova Z, Bepeyeva A, Stuart M. Cs-137 in milk, vegetation, soil, and water near the former Soviet Union's Semipalatinsk Nuclear Test Site. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:4931-4937. [PMID: 26549709 DOI: 10.1007/s11356-015-5741-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 11/03/2015] [Indexed: 06/05/2023]
Abstract
The present study was carried out to evaluate Cs-137 activity concentration in soil, water, vegetation, and cow's milk at 10 locations within three regions (Abai, Ayaguz, and Urdzhar) to the southeast of the Semipalatinsk Nuclear Test Site (SNTS) in Kazakhstan. Cs-137 activity concentrations, determined using a pure Ge gamma-ray spectrometer, showed that, all samples collected did not exceed the National maximum allowable limits of 10,000 Bq/kg for soil, 100 Bq/kg for cow's milk, 74 Bq/kg for vegetation, and 11 Bq/kg for water. Cs-137 is, therefore, not considered a health hazard in these regions. The highest levels of contamination were found in the Abai region, where the highest activity concentration of Cs-137 was 18.0 ± 1.0 Bq/kg in soil, 7.60 ± 0.31 Bq/kg in cow's milk, 4.00 ± 0.14 Bq/kg in the vegetation, and 3.00 ± 0.24 Bq/kg in water. The lowest levels were measured within the Urdzhar region, where 4.00 ± 0.14 Bq/kg was found in the soil, 0.30 ± 0.02 Bq/kg in the cow's milk, 1.00 ± 0.03 Bq/kg in the vegetation, and 0.20 ± 0.02 Bq/kg in the water.
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Affiliation(s)
- Aitbek Kakimov
- Shakarim State University of Semey, 20 A Glinki Street, 071412, Semey, Kazakhstan
| | - Zhanibek Yessimbekov
- Shakarim State University of Semey, 20 A Glinki Street, 071412, Semey, Kazakhstan.
| | - Zhainagul Kakimova
- Shakarim State University of Semey, 20 A Glinki Street, 071412, Semey, Kazakhstan
| | - Aigerim Bepeyeva
- Shakarim State University of Semey, 20 A Glinki Street, 071412, Semey, Kazakhstan
| | - Marilyne Stuart
- Canadian Nuclear Laboratories (formerly Atomic Energy of Canada Limited), 1 plant road, Chalk River, ON, K0J 1J0, Canada
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Liao H, Bu W, Zheng J, Wu F, Yamada M. Vertical distributions of radionuclides ((239+240)Pu, (240)Pu/(239)Pu, and (137)Cs) in sediment cores of Lake Bosten in Northwestern China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:3840-3846. [PMID: 24580087 DOI: 10.1021/es405364m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Artificial radionuclides ((137)Cs, (239+240)Pu, (241)Pu, (241)Am) deposited in lacustrine sediments have been used for dating as well as radionuclide source identification. In the present work, we investigated the vertical distributions of (239+240)Pu and (137)Cs activities, (240)Pu/(239)Pu atom ratios, and (239+240)Pu/(137)Cs activity ratios in sediment cores collected from Lake Bosten, which is the lake closest to the Lop Nor Chinese Nuclear Weapon Test site in northwestern China. Uniformly high concentrations of (239+240)Pu and (137)Cs were found in the upper layers deposited since 1964 in the sediment cores, and these were controlled by the resuspension of soil containing radionuclides from the nearby land surface. As the Chinese nuclear tests varied remarkably in yield, the mixing of the tropospheric deposition from these tests and the stratospheric deposition of global fallout has led to a (240)Pu/(239)Pu atom ratio that is similar to that of global fallout and to a (239+240)Pu/(137)Cs activity ratio that is slightly higher than that of global fallout. However, a low (240)Pu/(239)Pu atom ratio of 0.080 and high (239+240)Pu/(137)Cs activity ratio of 0.087, significantly different from the global fallout values, were observed in one sediment core (07BS10-2), indicating the inhomogenous tropospheric deposition from the Chinese nuclear tests in Lake Bosten during 1967-1973. These results are important to understand the influence of the CNTs on the radionuclide contamination in Lake Bosten.
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Affiliation(s)
- Haiqing Liao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences , Beijing 100012, China
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Wendel CC, Fifield LK, Oughton DH, Lind OC, Skipperud L, Bartnicki J, Tims SG, Høibråten S, Salbu B. Long-range tropospheric transport of uranium and plutonium weapons fallout from Semipalatinsk nuclear test site to Norway. ENVIRONMENT INTERNATIONAL 2013; 59:92-102. [PMID: 23792418 DOI: 10.1016/j.envint.2013.05.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 05/22/2013] [Accepted: 05/27/2013] [Indexed: 06/02/2023]
Abstract
A combination of state-of-the-art isotopic fingerprinting techniques and atmospheric transport modelling using real-time historical meteorological data has been used to demonstrate direct tropospheric transport of radioactive debris from specific nuclear detonations at the Semipalatinsk test site in Kazakhstan to Norway via large areas of Europe. A selection of archived air filters collected at ground level at 9 stations in Norway during the most intensive atmospheric nuclear weapon testing periods (1957-1958 and 1961-1962) has been screened for radioactive particles and analysed with respect to the concentrations and atom ratios of plutonium (Pu) and uranium (U) using accelerator mass spectrometry (AMS). Digital autoradiography screening demonstrated the presence of radioactive particles in the filters. Concentrations of (236)U (0.17-23nBqm(-3)) and (239+240)Pu (1.3-782μBqm(-3)) as well as the atom ratios (240)Pu/(239)Pu (0.0517-0.237) and (236)U/(239)Pu (0.0188-0.7) varied widely indicating several different sources. Filter samples from autumn and winter tended to have lower atom ratios than those sampled in spring and summer, and this likely reflects a tropospheric influence in months with little stratospheric fallout. Very high (236)U, (239+240)Pu and gross beta activity concentrations as well as low (240)Pu/(239)Pu (0.0517-0.077), (241)Pu/(239)Pu (0.00025-0.00062) and (236)U/(239)Pu (0.0188-0.046) atom ratios, characteristic of close-in and tropospheric fallout, were observed in filters collected at all stations in Nov 1962, 7-12days after three low-yield detonations at Semipalatinsk (Kazakhstan). Atmospheric transport modelling (NOAA HYSPLIT_4) using real-time meteorological data confirmed that long range transport of radionuclides, and possibly radioactive particles, from Semipalatinsk to Norway during this period was plausible. The present work shows that direct tropospheric transport of fallout from atmospheric nuclear detonations periodically may have had much larger influence on radionuclide air concentrations and deposition than previously anticipated.
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Affiliation(s)
- Cato Christian Wendel
- Isotope Laboratory, Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, N-1432 Aas, Norway.
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Evseeva T, Belykh E, Geras'kin S, Majstrenko T. Estimation of radioactive contamination of soils from the "Balapan" and the "Experimental field" technical areas of the Semipalatinsk nuclear test site. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2012; 109:52-59. [PMID: 22285594 DOI: 10.1016/j.jenvrad.2012.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 12/28/2011] [Accepted: 01/03/2012] [Indexed: 05/31/2023]
Abstract
In spite of the long history of the research, radioactive contamination of the Semipalatinsk nuclear test site (SNTS) in the Republic of Kazakhstan has not been adequately characterized. Our cartographic investigation has demonstrated highly variable radioactive contamination of the SNTS. The Cs-137, Sr-90, Eu-152, Eu-154, Co-60, and Am-241 activity concentrations in soil samples from the "Balapan" site were 42.6-17646, 96-18250, 1.05-11222, 0.6-4865, 0.23-4893, and 1.2-1037 Bq kg(-1), correspondingly. Cs-137 and Sr-90 activity concentrations in soil samples from the "Experimental field" site were varied from 87 up to 400 and from 94 up to 1000 Bq kg(-1), respectively. Activity concentrations of Co-60, Eu-152, and Eu-154 were lower than the minimum detectable activity of the method used. Concentrations of naturally occurring radionuclides (K-40, Ra-226, U-238, and Th-232) in the majority of soil samples from the "Balapan" and the "Experimental field" sites did not exceed typical for surrounding of the SNTS areas levels. Estimation of risks associated with radioactive contamination based on the IAEA clearance levels for a number of key radionuclides in solid materials shows that soils sampled from the "Balapan" and the "Experimental field" sites might be considered as radioactive wastes. Decrease in specific activity of soil from the sites studied up to safety levels due to Co-60, Cs-137, Sr-90, Eu-152, Eu-154 radioactive decay and Am-241 accumulation-decay will occur not earlier than 100 years. In contrast, soils from the "Experimental field" and the "Balapan" sites (except 0.5-2.5 km distance from the "Chagan" explosion point) cannot be regarded as the radioactive wastes according safety norms valid in Russia and Kazakhstan.
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Affiliation(s)
- T Evseeva
- Institute of Biology, Komi Scientific Center, Ural Division RAS, Kommunisticheskaya 28, 167982 Syktyvkar, Russia.
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Wu F, Zheng J, Liao H, Yamada M, Wan G. Anomalous plutonium isotopic ratios in sediments of Lake Qinghai from the Qinghai-Tibetan Plateau, China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:9188-9194. [PMID: 21950768 DOI: 10.1021/es202315c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The vertical profiles of (239+240)Pu and (137)Cs activities and (240)Pu/(239)Pu isotopic ratios are determined for three sediment cores of Lake Qinghai from the Qinghai-Tibetan Plateau, China, and compared with those in sediments of another three lakes (Lakes Bosten, Sugan, and Shuangta), the only existing ones closest to Lop Nor area, China's nuclear weapons test site in the northwestern part of the country. The mean inventory of 47.7 ± 18.7 MBq km(-2) for (239+240)Pu activity in Lake Qinghai is comparable to the average value of global fallout expected at the same latitude, yet the mean inventory of 1112.0 ± 78.0 MBq km(-2) for (137)Cs is slightly lower than that of global fallout. Anomalously low (240)Pu/(239)Pu isotopic ratios (0.038-0.125) were found in the 3-6.5 cm deep sediment layers, indicating the trace Pu input from early nuclear weapons research activities at Atomic City in the lake's watershed during the 1950-60s. Model calculation indicated that the Pu input accounted for approximately 5-16% of the total Pu inventory. The observation of low (240)Pu/(239)Pu ratio in the deep sediment layer provided a new time marker for recent sediment dating in the lake and around the area. The results are of great significance to the further understanding of sources, records, and environmental impacts of global and regional nuclear activities in the environment and provide important chronological information for further studies on the water eutrophication process and climatic change, and reconstruction of pollution history of organic contaminants and heavy metals in the watershed of Lake Qinghai.
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Affiliation(s)
- Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
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Imanaka T, Yamamoto M, Kawai K, Sakaguchi A, Hoshi M, Chaizhunusova N, Apsalikov K. Reconstruction of local fallout composition and gamma-ray exposure in a village contaminated by the first USSR nuclear test in the Semipalatinsk nuclear test site in Kazakhstan. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2010; 49:673-684. [PMID: 20532543 DOI: 10.1007/s00411-010-0301-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 05/22/2010] [Indexed: 05/29/2023]
Abstract
After the disintegration of the USSR in end of 1991, it became possible for foreign scientists to visit Kazakhstan, in order to investigate the radiological consequences of nuclear explosions that had been conducted at the Semipalatinsk nuclear test site (SNTS). Since the first visit in 1994, our group has been continuing expeditions for soil sampling at various areas around SNTS. The current level of local fallout at SNTS was studied through γ-spectrometry for (137)Cs as well as α-spectrometry for (239,240)Pu. Average values of soil inventory from wide areas around SNTS were 3,500 and 3,700 Bq m(-2) for (137)Cs and (239,240)Pu, respectively, as of January 1, 2000. The average level of (137)Cs is comparable to that in Japan due to global fallout, while the level of (239,240)Pu is several tens of times larger than that in Japan. Areas of strong contamination were found along the trajectories of radioactive fallout, information on which was declassified after the collapse of the USSR. Our recent efforts of soil sampling were concentrated on the area around the Dolon village heavily affected by the radioactive plume from the first USSR atomic bomb test in 1949 and located 110 km east from ground zero of the explosion. Using soil inventory data, retrospective dosimetry was attempted by reconstructing γ-ray exposure from fission product nuclides deposited on the ground. Adopting representative parameters for the initial (137)Cs deposition (13 kBq m(-2)), the refractory/volatile deposition ratio (3.8) and the plume arrival time after explosion (2.5 h), an absorbed dose in air of 600 mGy was obtained for the 1-year cumulative dose in Dolon village, due to the first bomb test in 1949. Considering possible ranges of the parameters, 350 and 910 mGy were estimated for high and low cases of γ-ray dose in air, respectively. It was encouraging that the deduced value was consistent with other estimations using thermal luminescence and archived monitoring data. The present method can be applied to other settlements affected by local fallout from SNTS.
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Affiliation(s)
- Tetsuji Imanaka
- Research Reactor Institute, Kyoto University, Sennan-gun, Osaka, Japan.
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Yamamoto M, Tomita J, Sakaguchi A, Ohtsuka Y, Hoshi M, Apsalikov KN. Uranium isotopes in well water samples as drinking sources in some settlements around the Semipalatinsk Nuclear Test Site, Kazakhstan. J Radioanal Nucl Chem 2010; 284:309-314. [PMID: 26224900 PMCID: PMC4514611 DOI: 10.1007/s10967-010-0463-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2009] [Indexed: 11/25/2022]
Abstract
Radiochemical results of U isotopes (234U, 235U and 238U) and their activity ratios are reported for well waters as local sources of drinking waters collected from the ten settlements around the Semipalatinsk Nuclear Test Site (SNTS), Kazakhstan. The results show that 238U varies widely from 3.6 to 356 mBq/L (0.3-28.7 μg/L), with a factor of about 100. The 238U concentrations in some water samples from Dolon, Tailan, Sarzhal and Karaul settlements are comparable to or higher than the World Health Organization's restrictive proposed guideline of 15 μg (U)/L. The 234U/238U activity ratios in the measured water samples are higher than 1, and vary between 1.1 and 7.9, being mostly from 1.5 to 3. The measured 235U/238U activity ratios are around 0.046, indicating that U in these well waters is of natural origin. It is probable that the elevated concentration of 238U found in some settlements around the SNTS is not due to the close-in fallout from nuclear explosions at the SNTS, but rather to the intensive weathering of rocks including U there. The calculated effective doses to adults resulting from consumption of the investigated waters are in the range 1.0-18.7 μSv/y. Those doses are lower than WHO and IAEA reference value (100 μSv/y) for drinking water.
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Affiliation(s)
- Masayoshi Yamamoto
- Low Level Radioactivity Laboratory, K-INET, Kanazawa University, Wake, Nomi-shi, Ishikawa 923-1224 Japan
| | - Junpei Tomita
- Low Level Radioactivity Laboratory, K-INET, Kanazawa University, Wake, Nomi-shi, Ishikawa 923-1224 Japan
| | - Aya Sakaguchi
- Faculty of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526 Japan
| | - Yoshihito Ohtsuka
- Institute of Environmental Sciences, Rokkasho-mura, Aomori, 039-3212 Japan
| | - Masaharu Hoshi
- International Radiation Information Center, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, 734-5883 Japan
| | - Kazbek N. Apsalikov
- Kazakh Scientific Research Institute for Radiation Medicine and Ecology, Semipalatinsk, The Kazakhstan Republic
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Lindahl P, Lee SH, Worsfold P, Keith-Roach M. Plutonium isotopes as tracers for ocean processes: a review. MARINE ENVIRONMENTAL RESEARCH 2010; 69:73-84. [PMID: 19773079 DOI: 10.1016/j.marenvres.2009.08.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Revised: 08/17/2009] [Accepted: 08/18/2009] [Indexed: 05/28/2023]
Abstract
Since the first nuclear weapons tests in the 1940s, pulsed inputs of plutonium isotopes have served as excellent tracers for understanding sources, pathways, dynamics and the fate of pollutants and particles in the marine environment. Due to the well-defined spatial and temporal inputs of Pu, the long half-lives of (240)Pu and (239)Pu and its unique chemical properties, Pu is a potential tracer for various physical and biogeochemical ocean processes, including circulation, sedimentation and biological productivity, and hence a means of assessing the impacts of global climate change. Due to the source dependency of the Pu isotopic signature, plutonium isotopes are beginning to be exploited as tools for the evaluation and improvement of regional and global ocean models that will enhance understanding of past and future changes in the oceans. This paper addresses the major sources of Pu and the physical and biogeochemical behaviour in the marine environment. Finally, the use of Pu isotopes as tracers for various oceanic processes (e.g. water mass transport, particle export, and sedimentation) is considered.
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Affiliation(s)
- Patric Lindahl
- Marine Environment Research Department, Korea Ocean Research and Development Institute, Ansan, P.O. Box 29, Seoul 425-600, Republic of Korea.
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Zhang Y, Zheng J, Yamada M, Wu F, Igarashi Y, Hirose K. Characterization of Pu concentration and its isotopic composition in a reference fallout material. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:1139-1144. [PMID: 20022080 DOI: 10.1016/j.scitotenv.2009.11.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Revised: 11/23/2009] [Accepted: 11/26/2009] [Indexed: 05/28/2023]
Abstract
Because there is no reference material for fallout plutonium isotope monitoring, preparation of such a material is necessary for quality control of fallout radionuclides analysis for atmospheric environmental studies. In this work, we report the characterization of Pu activity and its isotopic composition in a reference fallout material prepared by the Meteorological Research Institute (MRI), Japan. This material was prepared from samples collected at 14 stations throughout Japan in 1963-1979, with reference values of (137)Cs, (90)Sr and (239)(+)(240)Pu activities. We analyzed the activities of (239)(+)(240)Pu and (241)Pu, and the atom ratios of (240)Pu/(239)Pu and (241)Pu/(239)Pu using an isotope dilution sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS). The (239)(+)(240)Pu activities in this fallout material using acid leaching and total digestion were 6.56+/-0.20 mBq/g and 6.79+/-0.16 mBq/g, respectively. Atom ratios of (240)Pu/(239)Pu were 0.1915+/-0.0030 and 0.1922+/-0.0044, respectively. Both (240)Pu/(239)Pu and (241)Pu/(239)Pu atom ratios were slightly higher than those of global fallout, which could be attributed to the deposition of fallout radionuclides resulting from the Chinese nuclear weapons tests conducted in the 1970s. The dominant host phases of (239)(+)(240)Pu were found to be organic matter-sulfides (70%) with a relative high (240)Pu/(239)Pu atom ratio, and Fe-Mn oxides (19%) using a sequential extraction method.
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Affiliation(s)
- Yongsan Zhang
- State Key Laboratory of Environmental Geochemistry, Chinese Academy of Sciences, Guanshui Road 46, Guiyang 550002, China
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Zheng J, Yamada M, Wu F, Liao H. Characterization of Pu concentration and its isotopic composition in soils of Gansu in northwestern China. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2009; 100:71-75. [PMID: 19058885 DOI: 10.1016/j.jenvrad.2008.10.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 10/23/2008] [Accepted: 10/28/2008] [Indexed: 05/27/2023]
Abstract
The total 239+240Pu activities and 240Pu/239Pu atom ratios in surface soil samples (0-5cm) in the Kumtag Desert in western Gansu Province, and in a soil core sample in Lanzhou were investigated using a sector-field ICP-MS. In the surface soil samples, 239+240Pu activities in fine particles (<150microm) were 1.3-2.1 times of those in coarse particles (150microm-1mm) which ranged from 0.005 to 0.157mBq/g. Atom ratios of 240Pu/239Pu in the surface soils ranged from 0.168 to 0.192 with a mean of 0.182+/-0.008. The mean ratio was similar to the typical global fallout value although the Kumtag Desert was believed to have received close-in fallout derived from Chinese nuclear weapons tests mainly conducted in the 1970s. Furthermore, the mean 240Pu/239Pu atom ratio observed in the soil core sample in Lanzhou was similar to the typical global fallout value. In the soil core sample, 239+240Pu activities in the various layers ranged from 0.012 to 0.23mBq/g, and the inventory of 239+240Pu (32.4Bq/m2, 0-23cm) was slightly lower than that expected from global fallout (42Bq/m2) at the same latitude. Rapid downward migration of Pu isotopes was observed in Lanzhou soil core sample layers. The contribution of the 10-cm deep top layers of surface soils to total inventory was only 17%, while the contribution of deeper layers (10-23cm) was as high as 83%. The 239+240Pu activity levels and 240Pu/239Pu atom ratios in soils in Gansu Province, China are similar to those in atmospheric deposition samples collected in the spring in recent years in Japan.
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Affiliation(s)
- Jian Zheng
- Nakaminato Laboratory for Marine Radioecology, Environmental Radiation Effects Research Group, National Institute of Radiological Sciences, 3609 Isozaki-cho, Hitachinaka, Ibaraki 311-1202, Japan.
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Yamamoto M, Oikawa S, Sakaguchi A, Tomita J, Hoshi M, Apsalikov KN. Determination of 240Pu/239Pu isotopic ratios in human tissues collected from areas around the Semipalatinsk Nuclear Test Site by sector-field high resolution ICP-MS. HEALTH PHYSICS 2008; 95:291-299. [PMID: 18695410 DOI: 10.1097/01.hp.0000314807.29873.71] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Information on the 240Pu/239Pu isotope ratios in human tissues for people living around the Semipalatinsk Nuclear Test Site (SNTS) was deduced from 9 sets of soft tissues and bones, and 23 other bone samples obtained by autopsy. Plutonium was radiochemically separated and purified, and plutonium isotopes (239Pu and 240Pu) were determined by sector-field high resolution inductively coupled plasma-mass spectrometry. For most of the tissue samples from the former nine subjects, low 240Pu/239Pu isotope ratios were determined: bone, 0.125 +/- 0.018 (0.113-0.145, n = 4); lungs, 0.063 +/- 0.010 (0.051-0.078, n = 5); and liver, 0.148 +/- 0.026 (0.104-0.189, n = 9). Only 239Pu was detected in the kidney samples; the amount of 240Pu was too small to be measured, probably due to the small size of samples analyzed. The mean 240Pu/239Pu isotope ratio for bone samples from the latter 23 subjects was 0.152 +/- 0.034, ranging from 0.088 to 0.207. A significant difference (a two-tailed Student's t test; 95% significant level, alpha = 0.05) between mean 240Pu/239Pu isotope ratios for the tissue samples and for the global fallout value (0.178 +/- 0.014) indicated that weapons-grade plutonium from the atomic bombs has been incorporated into the human tissues, especially lungs, in the residents living around the SNTS. The present 239,240Pu concentrations in bone, lung, and liver samples were, however, not much different from ranges found for human tissues from other countries that were due solely to global fallout during the 1970's-1980's.
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Affiliation(s)
- M Yamamoto
- Low Level Radioactivity Laboratory, K-INET, Kanazawa University, Wake, Nomi-shi, Ishikawa 923-1224, Japan.
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Kim CK, Kim CS, Sansone U, Martin P. Development and application of an on-line sequential injection system for the separation of Pu, 210Po and 210Pb from environmental samples. Appl Radiat Isot 2008; 66:223-30. [PMID: 17890095 DOI: 10.1016/j.apradiso.2007.08.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Revised: 07/25/2007] [Accepted: 08/08/2007] [Indexed: 11/25/2022]
Abstract
An on-line sequential injection (SI) system was developed, which can be widely used for the separation and pre-concentration of target analytes from diverse environmental samples. The system enables the separation time to be shortened by maintaining a constant flow rate of solution and by avoiding clogging or bubbling in a chromatographic column. The SI system was successfully applied to the separation of Pu in IAEA reference material (IAEA Soil-6) and to the sequential separation of 210Po and 210Pb in a phosphogypsum candidate reference material. The replicate analysis results of Pu in IAEA reference material (Soil-6) obtained with the SI system are in good agreement with the recommended value within 5% of standard deviation. The SI system enabled a halving in the separation time required for radionuclides investigated.
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Affiliation(s)
- Chang-Kyu Kim
- Physics, Chemistry and Instrumentation Laboratory, IAEA, Agency's Laboratories, Seibersdorf, A-1400 Vienna, Austria.
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Everett SE, Tims SG, Hancock GJ, Bartley R, Fifield LK. Comparison of Pu and (137)Cs as tracers of soil and sediment transport in a terrestrial environment. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2008; 99:383-393. [PMID: 18063237 DOI: 10.1016/j.jenvrad.2007.10.019] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 10/24/2007] [Accepted: 10/24/2007] [Indexed: 05/25/2023]
Abstract
Following atmospheric nuclear weapons testing in the 1950s and 1960s significant quantities of (137)Cs and (239+240)Pu were deposited worldwide. In recent decades, (137)Cs has been commonly used as a tracer of soil erosion and sedimentation, particularly in the Northern Hemisphere where atomic deposition was three times as great as in the Southern Hemisphere. The relatively short 30-year half-life of this isotope means that its sensitivity as a tracer is rapidly decreasing. In contrast, with half-lives of 24,110 and 6561 years, the sensitivity of the two plutonium isotopes remains essentially the same as when it was deposited. Here we use the technique of Accelerator Mass Spectrometry to demonstrate the potential of anthropogenic Pu as an alternative to (137)Cs as a tracer of soil transport in Australia. We measure an average (137)Cs/(239+240)Pu activity ratio of 27.3+/-1.5 and an average (240)Pu/(239)Pu atom ratio of 0.149+/-0.003, both slightly lower than the global average.
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Affiliation(s)
- S E Everett
- Department of Nuclear Physics, Research School of Physical Sciences and Engineering, The Australian National University, Building 57, Canberra, 0200 ACT, Australia.
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23
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Yamamoto M, Hoshi M, Sakaguchi A, Shinohara K, Kurihara O, Apsalikov KN, Gusev BI. Plutonium and uranium in human bones from areas surrounding the Semipalatinsk nuclear test site. JOURNAL OF RADIATION RESEARCH 2006; 47 Suppl A:A85-94. [PMID: 16571950 DOI: 10.1269/jrr.47.a85] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
To evaluate the present levels of 239,240Pu and U in residents living near the Semipalatinsk nuclear test site, more than 70 bone samples were obtained at autopsy. The subjects ranged in age from 30 to 86 years (mean 59.3+/-12.9). Most of the samples consisted of victims who died of various diseases. Plutonium and U were radiochemically separated and determined by alpha-ray spectrometry. The mean concentrations of 239,240Pu and 238U observed were 0.050+/-0.041 mBq/g-ash (vertebrae 71, long-bones 18) and 0.28+/-0.13 mBq/g-ash (22.8+/-10.6 microg U/kg-ash) (vertebrae 58, long bones 16), respectively. The present 239,240Pu levels were within the range found for human bone samples from other countries due solely to global fallout in the early 1980s. The average U concentration was close to the estimate (mean 22.5 microg U/kg-ash) for the UK, and about 10 times higher than those estimated for residents in New York City and Japan. By assuming that the average concentration of 239,240Pu in bone samples is the value at 45 years after instantaneous inhalation in 1955, the initial total intake and the effective dose for 45 years were estimated as 10 Bq and 0.2 mSv, respectively. The annual intake of total U (234,235,238U) and its effective dose for 60 years were estimated as 30 Bq for adult and 0.1 mSv, respectively, for chronic ingestion.
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Affiliation(s)
- Masayoshi Yamamoto
- Low Level Radioactivity Laboratory, K-INET, Kanazawa University, Ishikawa, Japan.
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24
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Mitchell PI, Vintró LL, Omarova A, Burkitbayev M, Nápoles HJ, Priest ND. Tritium in well waters, streams and atomic lakes in the East Kazakhstan Oblast of the Semipalatinsk Nuclear Test Site. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2005; 25:141-8. [PMID: 15942057 DOI: 10.1088/0952-4746/25/2/002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The concentration of tritium has been determined in well waters, streams and atomic lakes in the Sarzhal, Tel'kem, Balapan and Degelen Mountains areas of the Semipalatinsk Test Site. The data show that levels of tritium in domestic well waters within the settlement of Sarzhal are extremely low at the present time with a median value of 4.4 Bq dm(-3) (95% confidence interval:4.1-4.7 Bq dm(-3)). These levels are only marginally above the background tritium content in surface waters globally. Levels in the atomic craters at Tel'kem 1 and Tel'kem 2 are between one and two orders of magnitude higher, while the level in Lake Balapan is approximately 12,600 Bq dm(-3). Significantly, levels in streams and test-tunnel waters sourced in the Degelen Mountains, the site of approximately 215 underground nuclear tests, are a further order of magnitude higher, being in the range 133,000--235,500 Bq dm(-3). No evidence was adduced which indicates that domestic wells in Sarzhal are contaminated by tritium-rich waters sourced in the Degelen massif, suggesting that the latter are not connected hydrologically to the near-surface groundwater recharging the Sarzhal wells. Annual doses to humans arising from the ingestion of tritium in these well waters are very low at the present time and are of no radiological significance.
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Affiliation(s)
- Peter I Mitchell
- Department of Experimental Physics, University College Dublin, Belfield, Dublin 4, Ireland.
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Plutonium, 137Cs and U in some pond and lake sediments from areas surrounding the Semipalatinsk Nuclear Test Site: With emphasis on anomalously high U accumulation. J Radioanal Nucl Chem 2005. [DOI: 10.1007/s10967-005-0483-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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