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Hirose K. Review of the sources and behaviors of plutonium isotopes in the atmosphere and ocean. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2024; 277:107466. [PMID: 38838510 DOI: 10.1016/j.jenvrad.2024.107466] [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: 12/19/2023] [Revised: 05/27/2024] [Accepted: 05/28/2024] [Indexed: 06/07/2024]
Abstract
Plutonium, as well as fission products such as 137Cs, had been released into the earth environment in 1945 after the first atmospheric nuclear explosion of plutonium bomb in the desert of New Mexico (USA, July 16) and later over Nagasaki (August 9), followed then by many other explosions. Thus, plutonium cycling in the atmosphere and ocean has become a major public concern as a result of the radiological and chemical toxicity of plutonium. However, plutonium isotopes and 137Cs are important transient tracers of biogeochemical and physical processes in the environment, respectively. In this review, we show that both physical and chemical approaches are needed to comprehensively understand the behaviors of plutonium in the atmosphere and ocean. In the atmosphere, plutonium and 137Cs attach with aerosols; thus, plutonium moves according to physical and chemical processes in connection with aerosols; however, since plutonium is a chemically reactive element, its behavior in an aqueous environment is more complicated, because biogeochemical regulatory factors, in addition to geophysical regulatory factors, must be considered. Meanwhile, 137Cs is chemically inert in aqueous environments. Therefore, the biogeochemical characteristics of plutonium can be elucidated through a comparison with those of 137Cs, which show conservative properties and moves according to physical processes. Finally, we suggest that monitoring of both plutonium and 137Cs can help elucidate geophysical and biogeochemical changes from climate changes.
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Affiliation(s)
- Katsumi Hirose
- Laboratory for Environmental Research at Mount Fuji, Okubo Shinjyuku-ku, Tokyo, Japan.
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2
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Nalichowska E, Mietelski JW, Kierepko R, Ustrnul Z, Gorzkiewicz K, Brudecki K, Kowalska A. Plutonium isotopes in the ground air layer in southern Poland (2010-2016): Source terms, seasonal variability and correlations with meteorological conditions. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 264:107204. [PMID: 37235923 DOI: 10.1016/j.jenvrad.2023.107204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/07/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023]
Abstract
In this study, the results of the analysis of Pu-238 and Pu-239 + 240 activity concentrations on aerosol filters collected from 2010 to 2016 in Krakow (Southern Poland) are presented and discussed. For the first time, the temporal variation of Pu-239 + 240 activity concentration in surface air in Poland was studied using Fourier analysis. The analysis clearly showed that the Pu-239 + 240 content in the near-ground air layer is subject to seasonal variations and demonstrates annual periodicity. Pu analyses were performed using alpha spectrometry. The measured values ranged from 1.93∙10-10 Bq/m3 to 1.31∙10-8 Bq/m3 with an average of 2.07∙10-9 Bq/m3 for Pu-239 + 240 and from 9.07∙10-11 Bq/m3 to 1.27∙10-9 Bq/m3 with the average 1.52∙10-10 Bq/m3 for Pu-238. The analysis of the potential sources of plutonium isotopes in the air aerosols samples indicated that only two samples are uniquely characterized by the ratio corresponding to spent nuclear fuel: February 2012 (0.59 ± 0.18) and February 2015 (0.68 ± 0.19). The remaining samples showed mixed origins, with global radioactive fallout appearing to contribute more than spent nuclear fuel. To study the relationship between Pu-239 + 240 and meteorological conditions, Pearson's correlation and circulation pattern analyses were performed. The analyses showed that the Pu-239 + 240 activity concentration depends on air temperature (R = 0.51), the sum of ice and snowfall (R = -0.45), relative humidity (R = -0.54) and mean total cloud cover (R = -0.56). High concentrations of Pu-239 + 240 were positively correlated with air advection from the southern and eastern sectors, whereas low concentrations were observed during dynamic weather conditions with intense circulation from the western sector. In case of Pu-238 no significant correlation was observed.
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Affiliation(s)
- Ewa Nalichowska
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland.
| | - Jerzy Wojciech Mietelski
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Renata Kierepko
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Zbigniew Ustrnul
- Jagiellonian University in Krakow, Department of Climatology, Gronostajowa 7, 30-387, Krakow, Poland
| | - Krzysztof Gorzkiewicz
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Kamil Brudecki
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Agata Kowalska
- Wrocław University of Science and Technology, Faculty of Geoengineering, Mining and Geology, Na Grobli 15, 50-421, Wrocław, Poland
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Feng D, Ji M, Liao H, Yang F, Zhou X, Pan T, Lu C, Luo J, Miao Y. An overview of plutonium isotopes in soils, China: Distribution, spatial patterns, and sources. ENVIRONMENTAL RESEARCH 2023; 216:114677. [PMID: 36374654 DOI: 10.1016/j.envres.2022.114677] [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: 06/19/2022] [Revised: 10/21/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Plutonium (Pu) is an anthropogenic radionuclide which has drawn significant attentions due to its radiotoxicity, and the sources of plutonium linked with nuclear accidents and contaminations. The 240Pu/239Pu atom ratio is source dependent and can be used as a fingerprint to determine the sources of radioactive contaminant. However, the distribution and sources of plutonium in soils of China have not yet been systematically studied at a national scale up to date. The distribution, spatial patterns, and sources of plutonium in soils of China were discussed in this work. The concentrations of 239,240Pu are in the range of 0.002-4.824 mBq/g with a large variation, and the 239,240Pu concentrations in surface soils increase with the increasing latitude, which affects by multi-factors such as organic matter and particle size, etc. The inventories of 239,240Pu are in the range of 7.31-554 Bq/m2. The weighted average of 240Pu/239Pu atom ratios (0.180 ± 0.004) in all surface samples is good agreement with the ratio of global fallout (0.180 ± 0.014) of the nuclear weapons tests, this indicate that the major source of plutonium in China is global fallout. However, among some sites, distinctly lower 240Pu/239Pu atom ratio compared to the global fallout values were observed in the northwest China, indicating a significant contribution from other source besides the global fallout. Furthermore, the spatial clustering patterns of hot spots (high values) and cold spots (low values) for plutonium showing the clear associations with nuclear tests, especially the Chinese Lop Nor nuclear weapons tests (CNTs) and the Semipalatinsk nuclear weapons tests (STS). Radioactive material including plutonium from the STS or CNTs was transported by the prevailing westerlies to the northwest China. This review about the fingerprints and distribution of plutonium in soils of China will help researchers to establish a reference database for future radiation risk assessment and environmental radioactive management.
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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
| | - Meichen Ji
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Haiqing Liao
- 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
| | - Xingxuan Zhou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Ting Pan
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Chaojun Lu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Jingtian Luo
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yunge Miao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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4
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Mietelski JW, Mróz T, Brudecki K, Janowski P, Dziedzic B. On a risk of inhalation exposure during visits in Chernobyl exclusion zone. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2022; 251-252:106972. [PMID: 35988319 DOI: 10.1016/j.jenvrad.2022.106972] [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: 02/24/2022] [Revised: 07/10/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
In recent years Chernobyl exclusion zone has become a very popular tourist destination. Many people visiting power plant, Pripyat city or surrounding villages use different types of personal dosimeters to control external exposure, however very small group of tourist have opportunity to control internal contamination of respiratory tract using dedicated, high sensitive whole body counters. In this study 11 anti-dust masks collected from CEZ visitors and filters from one military MP-5 mask were analyzed using alpha, beta and gamma spectrometry to determine doses from actinides and fission products which can be inhaled without proper protective equipment. Results showed, that average effective dose from inhalation of contaminated aerosol in case of single-day trip (avoided due to use of mask) was 1.3 μSv per person, which is much smaller than potential effective dose after exploration of highly contaminated areas like Jupiter complex, where combined dose from all measured nuclides collected on MP-5 mask filter was 1.4 mSv.
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Affiliation(s)
- Jerzy W Mietelski
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego o152, 31-342, Kraków, Poland.
| | - Tomasz Mróz
- Institute of Physics, Jagiellonian University, Łojasiewicz 11, 30-348, Kraków, Poland
| | - Kamil Brudecki
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego o152, 31-342, Kraków, Poland
| | - Paweł Janowski
- Department of Physics and Applied Informatics, AGH Technical University, Reymonta 19, 30-059, Kraków, Poland
| | - Bartosz Dziedzic
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego o152, 31-342, Kraków, Poland
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5
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Sung SH, Kim MJ, Kim HR. Accuracy comparison of fitting function applied to air-borne alpha detection spectrum. PROGRESS IN NUCLEAR ENERGY 2021. [DOI: 10.1016/j.pnucene.2021.103737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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6
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Sung SH, Kim HR. Optimization of airborne alpha beta detection system modeling using MCNP simulation. NUCLEAR ENGINEERING AND TECHNOLOGY 2020. [DOI: 10.1016/j.net.2019.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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7
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Cwanek A, Mietelski JW, Łokas E, Olech MA, Anczkiewicz R, Misiak R. Sources and variation of isotopic ratio of airborne radionuclides in Western Arctic lichens and mosses. CHEMOSPHERE 2020; 239:124783. [PMID: 31726517 DOI: 10.1016/j.chemosphere.2019.124783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 08/24/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
This research concerned radioactivity of lichens and mosses from coastal zones of the Canadian Arctic and Alaska. Over 50 samples were collected from 7 positions during two scientific expeditions in 2012 and 2013. The tundra contamination caused by anthropogenic radionuclides was relatively low, reaching mean values with SD's of: 17.4 ± 3.5 Bq/kg for 90Sr, 14.0 ± 2.9 Bq/kg for 134Cs, 38.4 ± 7.5 Bq/kg for 137Cs, 0.86 ± 0.24 Bq/kg for 239+240Pu, 0.065 ± 0.017 Bq/kg for 238Pu and 0.50 ± 0.13 Bq/kg for 241Am. The increase of activity concentration with increasing latitudes was noticed mostly in regard to 90Sr, Pu isotopes and 241Am. The analysis of isotopic ratios exhibited dominant contribution of the global fallout (+SNAP 9A satellite re-entry fallout) for the presence of plutonium isotopes and 241Am. The Fukushima fallout signature was identified in a few lichens from Alaska. However, the influence of additional unknown factor on the occurrence of 90Sr and 137Cs has been detected in western part of Canadian Arctic. Natural radioisotopes of thorium and uranium were found throughout the entire investigated region and the average values of activity concentration with SD's were as follows: 2.92 ± 0.47 Bq/kg for 230Th, 2.61 ± 0.48 Bq/kg for 232Th, 4.32 ± 0.80 Bq/kg for 234U and 3.97 ± 0.71 Bq/kg for 238U. Examined Western Arctic tundra was not affected with any technically enhanced natural radioactivity.
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Affiliation(s)
- Anna Cwanek
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland.
| | - Jerzy W Mietelski
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Edyta Łokas
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Maria A Olech
- Institute of Botany, Jagiellonian University, Lubicz 46, 31-512, Krakow, Poland
| | - Robert Anczkiewicz
- Institute of Geological Sciences, Polish Academy of Sciences, Kraków Research Centre, Senacka 1, 31-002, Krakow, Poland
| | - Ryszard Misiak
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
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8
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Hou X, Zhang W, Wang Y. Determination of Femtogram-Level Plutonium Isotopes in Environmental and Forensic Samples with High-Level Uranium Using Chemical Separation and ICP-MS/MS Measurement. Anal Chem 2019; 91:11553-11561. [DOI: 10.1021/acs.analchem.9b01347] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- 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
- Center for Nuclear Technologies, Technical University of Denmark, DTU Nutech, Roskilde DK-4000, 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
| | - 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
- University of Chinese Academy of Sciences, Beijing 100049, 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
- University of Chinese Academy of Sciences, Beijing 100049, China
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9
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Kierepko R, Sahoo SK, Hosoda M, Tokonami S, Sorimachi A, Kim E, Ohno M. 238Pu/ (239+240)Pu activity ratio as an indicator of Pu originating from the FDNPP accident in the terrestrial environment of Fukushima Prefecture. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 196:133-140. [PMID: 30453130 DOI: 10.1016/j.jenvrad.2018.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 11/08/2018] [Accepted: 11/08/2018] [Indexed: 06/09/2023]
Abstract
The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident has caused significant radionuclide contamination. Pu isotopes at the level of GBq were released from the damaged reactors to terrestrial and marine ecosystems. In this work, 35 samples were collected at different locations of Fukushima. Samples consisted of three types, soil, forest litter and alluvial dust (road dust, sludges from drainage systems and below gutter pipe outflows). The obtained activity ratios of 238Pu/(239+240)Pu ranged from 0.030 to 1.86. 14 of our samples contained trace amounts of Pu originating from the damaged reactors (2SM verification). Our study identified a few previously unknown "hot spots" of 238Pu/(239+240)Pu activity ratio localized in an area between 15 and 30 km in the northwest direction from the FDNPP. Additionally, results obtained in this study combined with previously published data allowed us to prepare a map of spatial distribution of the Pu isotope fingerprints (238Pu/(239+240)Pu) in Fukushima Prefecture.
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Affiliation(s)
- R Kierepko
- Fukushima Project Headquarters, National Institute for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan; Department of Nuclear Physical Chemistry, Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Radzikowskiego 152, Poland
| | - S K Sahoo
- Fukushima Project Headquarters, National Institute for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
| | - M Hosoda
- Department of Radiation Sciences, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan
| | - S Tokonami
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan
| | - A Sorimachi
- Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori, 036-8564, Japan; Department of Radiation Physics and Chemistry, School of Medicine, Fukushima Medical University, Hikarigaoka 1, Fukushima, 960-1295, Japan
| | - E Kim
- Department of Radiation Measurement and Dose Assessment, National Institute for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - M Ohno
- Department of Radiation Measurement and Dose Assessment, National Institute for Quantum and Radiological Sciences and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
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10
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Thakur P, Ward AL. 241Pu in the environment: insight into the understudied isotope of plutonium. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-5946-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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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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12
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Łokas E, Wachniew P, Jodłowski P, Gąsiorek M. Airborne radionuclides in the proglacial environment as indicators of sources and transfers of soil material. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 178-179:193-202. [PMID: 28881250 DOI: 10.1016/j.jenvrad.2017.08.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 08/25/2017] [Accepted: 08/25/2017] [Indexed: 06/07/2023]
Abstract
A survey of artificial (137Cs, 238Pu, 239+240Pu, 241Am) and natural (226Ra, 232Th, 40K, 210Pb) radioactive isotopes in proglacial soils of an Arctic glacier have revealed high spatial variability of activity concentrations and inventories of the airborne radionuclides. Soil column 137Cs inventories range from below the detection limit to nearly 120 kBq m-2, this value significantly exceeding direct atmospheric deposition. This variability may result from the mixing of materials characterised by different contents of airborne radionuclides. The highest activity concentrations observed in the proglacial soils may result from the deposition of cryoconites, which have been shown to accumulate airborne radionuclides on the surface of glaciers. The role of cryoconites in radionuclide accumulation is supported by the concordant enrichment of the naturally occurring airborne 210Pb in proglacial soil cores showing elevated levels of artificial radionuclides. The lithogenic radionuclides show less variability than the airborne radionuclides because their activity concentrations are controlled only by the mixing of material derived from the weathering of different parent rocks. Soil properties vary little within and between the profiles and there is no unequivocal relationship between them and the radionuclide contents. The inventories reflect the pathways and time variable inputs of soil material to particular sites of the proglacial zone. Lack of the airborne radionuclides reflects no deposition of material exposed to the atmosphere after the 1950s or its removal by erosion. Inventories above the direct atmospheric deposition indicate secondary deposition of radionuclide-bearing material. Very high inventories indicate sites where transport pathways of cryoconite material terminated.
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Affiliation(s)
- Edyta Łokas
- Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow, Poland.
| | - Przemysław Wachniew
- AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Krakow, Poland.
| | - Paweł Jodłowski
- AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Krakow, Poland.
| | - Michał Gąsiorek
- University of Agriculture, Department of Soil Science and Soil Protection, Al. Mickiewicza 21, 31-120 Kraków, Poland.
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Gückel K, Shinonaga T, Christl M, Tschiersch J. Scavenged 239Pu, 240Pu, and 241Am from snowfalls in the atmosphere settling on Mt. Zugspitze in 2014, 2015 and 2016. Sci Rep 2017; 7:11848. [PMID: 28928452 PMCID: PMC5605513 DOI: 10.1038/s41598-017-12079-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 09/04/2017] [Indexed: 11/24/2022] Open
Abstract
Concentrations of 239Pu, 240Pu, and 241Am, and atomic ratio of 240Pu/239Pu in freshly fallen snow on Mt. Zugspitze collected in 2014, 2015 and 2016 were determined by accelerator mass spectrometry (AMS). For the sub-femtogram (10-15 g) - level of Pu and Am analysis, a chemical separation procedure combined with AMS was improved and an excellent overall efficiency of about 10-4 was achieved. The concentration of 239Pu ranges from 75 ± 13 ag/kg to 2823 ± 84 ag/kg, of 240Pu from 20.6 ± 5.2 to 601 ± 21 ag/kg, and of 241Am was found in the range of 16.7 ± 5.0-218.8 ± 8.9 ag/kg. Atomic ratios of 240Pu/239Pu for most samples are comparable to the fallout in middle Europe. One exceptional sample shows a higher Pu concentration. High airborne dust concentration, wind directions, high Cs concentrations and the activity ratio of 239+240Pu/137Cs lead to the conclusion that the sample was influenced by Pu in Saharan dust transported to Mt. Zugspitze.
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Affiliation(s)
- Katharina Gückel
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.
| | - Taeko Shinonaga
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
- Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, Aomori, 036-8564, Japan
| | - Marcus Christl
- Laboratory of Ion Beam Physics, ETH Zurich, 8093, Zurich, TS, Switzerland
| | - Jochen Tschiersch
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
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14
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Thakur P, Khaing H, Salminen-Paatero S. Plutonium in the atmosphere: A global perspective. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 175-176:39-51. [PMID: 28432864 DOI: 10.1016/j.jenvrad.2017.04.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/06/2017] [Accepted: 04/09/2017] [Indexed: 06/07/2023]
Abstract
A number of potential source terms have contributed plutonium isotopes to the atmosphere. The atmospheric nuclear weapon tests conducted between 1945 and 1980 and the re-entry of the burned SNAP-9A satellite in 1964, respectively. It is generally believed that current levels of plutonium in the stratosphere are negligible and compared with the levels generally found at surface-level air. In this study, the time trend analysis and long-term behavior of plutonium isotopes (239+240Pu and 238Pu) in the atmosphere were assessed using historical data collected by various national and international monitoring networks since 1960s. An analysis of historical data indicates that 239+240Pu concentration post-1984 is still frequently detectable, whereas 238Pu is detected infrequently. Furthermore, the seasonal and time-trend variation of plutonium concentration in surface air followed the stratospheric trends until the early 1980s. After the last Chinese test of 1980, the plutonium concentrations in surface air dropped to the current levels, suggesting that the observed concentrations post-1984 have not been under stratospheric control, but rather reflect the environmental processes such as resuspension. Recent plutonium atmospheric air concentrations data show that besides resuspension, other environmental processes such as global dust storms and biomass burning/wildfire also play an important role in redistributing plutonium in the atmosphere.
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Affiliation(s)
- P Thakur
- Carlsbad Environmental Monitoring & Research Center, 1400 University Drive, Carlsbad, NM 88220, USA.
| | - H Khaing
- Carlsbad Environmental Monitoring & Research Center, 1400 University Drive, Carlsbad, NM 88220, USA
| | - S Salminen-Paatero
- Department of Chemistry - Radiochemistry, P.O. Box 55, 00014, University of Helsinki, Finland
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15
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Łokas E, Anczkiewicz R, Kierepko R, Mietelski JW. Variations in Pu isotopic composition in soils from the Spitsbergen (Norway): Three potential pollution sources of the Arctic region. CHEMOSPHERE 2017; 178:231-238. [PMID: 28324843 DOI: 10.1016/j.chemosphere.2017.03.054] [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: 01/19/2017] [Revised: 03/09/2017] [Accepted: 03/12/2017] [Indexed: 06/06/2023]
Abstract
Although the polar regions have not been industrialised, numerous contaminants originating from human activity are detectable in the Arctic environment. This study reports evidence of 240Pu/239Pu atomic ratios in the tundra and initial soils from different parts of west and central Spitsbergen and recognizes possible environmental inputs of non-global fallout Pu. The average atomic ratio of 240Pu/239Pu equal to 0.179 (ranging between 0.129 and 0.201) in tundra soils are comparable to the characteristic ratio for global fallout (0.180). However, the 240Pu/239Pu atomic ratios in the initial soils from proglacial zone of glaciers change within wide range between 0.1281 and 0.234 with the mean value of 0.169. By combining alpha and mass spectrometry, the three-sources model was used to identify the Pu sources in initial soils. Our study indicated that the main source of Pu is nuclear tests and that a second source with lower Pu ratio may come from weapons grade Pu (unexploded weapons grade Pu ie. material from bomb which didn't undergo nuclear explosions for example for security tests). Additionally, we found samples with high 238Pu/239+240Pu activity ratios and with typical global fallout 240Pu/239Pu atomic ratios, which are associated with separate sources of pure 238Pu from the SNAP-9A satellite burn up in the atmosphere.
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Affiliation(s)
- E Łokas
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland.
| | - R Anczkiewicz
- Institute of Geological Sciences, Polish Academy of Sciences, Senacka 1, 31-002, Krakow, Poland
| | - R Kierepko
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
| | - J W Mietelski
- Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342, Krakow, Poland
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16
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Sources of plutonium in the atmosphere and stratosphere-troposphere mixing. Sci Rep 2015; 5:15707. [PMID: 26508010 PMCID: PMC4623714 DOI: 10.1038/srep15707] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 09/15/2015] [Indexed: 11/25/2022] Open
Abstract
Plutonium isotopes have primarily been injected to the stratosphere by the atmospheric nuclear weapon tests and the burn-up of the SNAP-9A satellite. Here we show by using published data that the stratospheric plutonium exponentially decreased with apparent residence time of 1.5 ± 0.5 years, and that the temporal variations of plutonium in surface air followed the stratospheric trends until the early 1980s. In the 2000s, plutonium and its isotope ratios in the atmosphere varied dynamically, and sporadic high concentrations of 239,240Pu reported for the lower stratospheric and upper tropospheric aerosols may be due to environmental events such as the global dust outbreaks and biomass burning.
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