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Zhao X, Hou X, Huang Z, Tang L. Source, preservation and re-suspension of 239,240Pu in a well dated peat core collected from northwest China. CHEMOSPHERE 2024; 359:142267. [PMID: 38719122 DOI: 10.1016/j.chemosphere.2024.142267] [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: 11/28/2023] [Revised: 04/21/2024] [Accepted: 05/04/2024] [Indexed: 05/12/2024]
Abstract
Owning to the high radiotoxicity in high concentrations, as well as the irreplaceability in quantifying soil erosion rates, demarcating the Anthropocene, and dating of sediment, anthropogenic 239,240Pu have drawn high attention. However, the source in specific areas, preservation characteristics in different environment media, and re-distribution process after the cessation of atmospheric nuclear weapons tests, have not been fully understood, which obscures the exact start year, temporal variation, and deposition flux of 239,240Pu in sedimentary records, and hinders the wide application of 239,240Pu in environment study. A sediment core from the Yiwu peat bog with dominance of atmospheric deposition in the source material, simple sedimentary environment, and high dust deposition flux, was collected to examine the 239,240Pu, and explore the source, preservation, and re-distribution process. The double peaks of 239,240Pu in 1952 CE and 1963 CE, as well as 240Pu/239Pu ratios of 0.163-0.190 with an average of 0.177 ± 0.010 confirmed that the 239,240Pu source originated predominantly from global fallout. The minimal vertical migration of plutonium in the Yiwu peat core was attributed to the near-neutral pH condition. The high inventory of 128 ± 7 Bq m-2, as well as the atypical negative correlation between 239,240Pu concentrations and organic matter content (r = - 0.79, P < 0.01), was attributed to the contribution of 239,240Pu re-suspended with dust from the neighboring Gobi Desert, particularly in the cold and dry years. The total re-suspended 239,240Pu was estimated to be 77 Bq m-2, exceeding the direct fallout level of 51 Bq m-2 during 1945-2016 CE. In this study, the specified deposition pattern of 239,240Pu after the cessation of atmospheric nuclear weapons was established, providing an important standard for multiple environmental studies, and the re-suspended amount of 239,240Pu in a typical arid area was quantified for the first time.
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Affiliation(s)
- Xue Zhao
- State Key Laboratory of Loess Science, 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, PR China; Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, PR China; Open Studio for Oceanic-Continental Climate and Environment Changes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266061, PR China
| | - Xiaolin Hou
- State Key Laboratory of Loess Science, 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, PR China; Open Studio for Oceanic-Continental Climate and Environment Changes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266061, PR China.
| | - Zhao Huang
- State Key Laboratory of Loess Science, 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, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Lu Tang
- Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, PR China
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2
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Zheng J, Tagami K, Uchida S, Shibutani S, Ishida K, Hamamoto T. Assessment of soil-soil solution distribution coefficients of global fallout 237Np and 239Pu in Japanese upland soils. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 266-267:107241. [PMID: 37454645 DOI: 10.1016/j.jenvrad.2023.107241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/05/2023] [Accepted: 07/09/2023] [Indexed: 07/18/2023]
Abstract
Neptunium-237 and 239Pu are important radionuclides in the safety assessment related to geological disposal of radioactive waste because of the possibility of long-term exposure to humans. Mobilities of these radionuclides in the environment are of particular importance for their radiation dose evaluation; therefore, in this study, we have made the assessment of the soil-soil solution distribution coefficient (Kd, L/kg) using global fallout 237Np and 239Pu in Japanese upland soils. The Kd values were determined by extracting these radionuclides from 24 soil samples using a laboratory batch method. The desorption Kd values of 237Np ranged from 3.3 × 102 to 1.0 × 104 L/kg, and their geometric mean (GM) and arithmetic mean (AM) were 1.7 × 103 L/kg and 2.6 × 103 L/kg, respectively. The desorption Kd values of 239Pu were found to vary from 9.4 × 103 to 7.1 × 104 L/kg, and their GM and AM were 3.3 × 104 L/kg and 4.0 × 104 L/kg, respectively. In Japanese upland soils, the Kd value of 239Pu was one order of magnitude higher than that of 237Np.
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Affiliation(s)
- Jian Zheng
- National Institute for Radiological Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Keiko Tagami
- National Institute for Radiological Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Shigeo Uchida
- National Institute for Radiological Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Sanae Shibutani
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Keisuke Ishida
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Takafumi Hamamoto
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
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3
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Lukashenko SN, Edomskaya MA. Plutonium in the Environment: Sources, Dissemination Mechanisms, and Concentrations. BIOL BULL+ 2022. [DOI: 10.1134/s1062359022110139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Zheng J, Tagami K, Uchida S, Shibutani S, Ishida K, Hamamoto T. Soil-soil solution distribution coefficients of global fallout 239Pu and 237Np in Japanese paddy soils. CHEMOSPHERE 2022; 291:132775. [PMID: 34752838 DOI: 10.1016/j.chemosphere.2021.132775] [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: 09/09/2021] [Revised: 10/23/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
239Pu and 237Np are long-lived radionuclides that emit alpha rays, and once released into the environment, they are present there for a long period of time. Therefore,239Pu and 237Np are important radionuclides in the safety assessment related to geological disposal of radioactive waste because of the possibility of long-term exposure to humans. Mobilities of these radionuclides in the environment are of particular interest; therefore, in this study, we have made the first-time determination of the soil-soil solution distribution coefficient (Kd, L/kg) using global fallout 239Pu and 237Np in soil. The Kd values were determined by extracting these radionuclides from 23 soil samples using a laboratory batch method. The desorption Kd values of 239Pu were found to vary from 3.2 × 103 to 1.4 × 105 L/kg, and their geometric mean (GM) and arithmetic mean (AM) were 2.3 × 104 L/kg and 3.2 × 104 L/kg, respectively. The desorption Kd values of 237Np ranged from 8.9 × 102 to 2.1 × 104 L/kg, and their GM and AM were 4.1 × 103 L/kg and 6.4 × 103 L/kg, respectively. A comparison between the obtained Kd values of 239Pu and 237Np indicated that the former were about 6-fold higher than the latter in Japanese paddy field soils. Pearson's correlation analysis suggested that the main factors contributing to the sorption and desorption of Pu isotopes in Japanese paddy soils were related to the amounts of Fe and Mn oxides, while the sorption and desorption of 237Np in them would be controlled by an ion-exchange reaction, and/or complex-formation with organic matter, especially in Fluvisols.
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Affiliation(s)
- Jian Zheng
- National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Keiko Tagami
- National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Shigeo Uchida
- National Institute of Radiological Sciences, National Institute for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Sanae Shibutani
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Keisuke Ishida
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
| | - Takafumi Hamamoto
- Nuclear Waste Management Organization of Japan, 4-1-23 Shiba, Minato-ku, Tokyo, 108-0014, Japan
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Johansen MP, Anderson D, Child D, Hotchkis MAC, Tsukada H, Okuda K, Hinton TG. Differentiating Fukushima and Nagasaki plutonium from global fallout using 241Pu/ 239Pu atom ratios: Pu vs. Cs uptake and dose to biota. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:141890. [PMID: 32916482 DOI: 10.1016/j.scitotenv.2020.141890] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/19/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
Plutonium (Pu) has been released in Japan by two very different types of nuclear events - the 2011 Fukushima accident and the 1945 detonation of a Pu-core weapon at Nagasaki. Here we report on the use of Accelerator Mass Spectrometry (AMS) methods to distinguish the FDNPP-accident and Nagasaki-detonation Pu from worldwide fallout in soils and biota. The FDNPP-Pu was distinct in local environmental samples through the use of highly sensitive 241Pu/239Pu atom ratios. In contrast, other typically-used Pu measures (240Pu/239Pu atom ratios, activity concentrations) did not distinguish the FDNPP Pu from background in most 2016 environmental samples. Results indicate the accident contributed new Pu of ~0.4%-2% in the 0-5 cm soils, ~0.3%-3% in earthworms, and ~1%-10% in wild boar near the FDNPP. The uptake of Pu in the boar appears to be relatively uninfluenced by the glassy particle forms of fallout near the FDNPP, whereas the 134,137Cs uptake appears to be highly influenced. Near Nagasaki, the lasting legacy of Pu is greater with high percentages of Pu sourced from the 1945 detonation (~93% soils, ~88% earthworm, ~96% boar). The Pu at Nagasaki contrasts with that from the FDNPP in having proportionately higher 239Pu and was distinguished by both 240Pu/239Pu and 241Pu/239Pu atom ratios. However, compared with the contamination near the Chernobyl accident site, the Pu amounts at all study sites in Japan are orders of magnitude lower. The dose rates from Pu to organisms in the FDNPP and Nagasaki areas, as well as to human consumers of wild boar meat, have been only slightly elevated above background. Our data demonstrate the greater sensitivity of 241Pu/239Pu atom ratios in tracing Pu from nuclear releases and suggest that the Nagasaki-detonation Pu will be distinguishable in the environment for much longer than the FDNPP-accident Pu.
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Affiliation(s)
- Mathew P Johansen
- Australian Nuclear Science and Technology Organisation, Sydney, Australia.
| | - Donovan Anderson
- Institute of Environmental Radioactivity, Fukushima University, 960-1248, Fukushima Prefecture, Fukushima, Kanayagawa, Japan; Symbiotic Systems Science and Technology, Fukushima University, 960-1248, Fukushima Prefecture, Fukushima, Kanayagawa, Japan
| | - David Child
- Australian Nuclear Science and Technology Organisation, Sydney, Australia
| | | | - Hirofumi Tsukada
- Institute of Environmental Radioactivity, Fukushima University, 960-1248, Fukushima Prefecture, Fukushima, Kanayagawa, Japan
| | - Kei Okuda
- Faculty of Human Environmental Studies, Hiroshima Shudo University, 731-3195, Hiroshima Prefecture, Asaminami-ku, Ozuka-higashi, Japan
| | - Thomas G Hinton
- Institute of Environmental Radioactivity, Fukushima University, 960-1248, Fukushima Prefecture, Fukushima, Kanayagawa, Japan; CERAD CoE, Norwegian University of Life sciences, Faculty for Environmental Sciences and Nature Research Management, Aas, Norway
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Lin P, Xu C, Kaplan DI, Chen H, Yeager CM, Xing W, Sun L, Schwehr KA, Yamazaki H, Saito-Kokubu Y, Hatcher PG, Santschi PH. Nagasaki sediments reveal that long-term fate of plutonium is controlled by select organic matter moieties. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 678:409-418. [PMID: 31077919 DOI: 10.1016/j.scitotenv.2019.04.375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/23/2019] [Accepted: 04/25/2019] [Indexed: 06/09/2023]
Abstract
Forecasting the long-term fate of plutonium (Pu) is becoming increasingly important as more worldwide military and nuclear-power waste is being generated. Nagasaki sediments containing bomb-derived Pu that was deposited in 1945 provided a unique opportunity to explore the long-term geochemical behavior of Pu. Through a combination of selective extractions and molecular characterization via electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FTICRMS), we determined that 55 ± 3% of the bomb-derived 239,240Pu was preferentially associated with more persistent organic matter compounds in Nagasaki sediments, particularly those natural organic matter (NOM) stabilized by Fe oxides (NOMFe-oxide). Other organic matter compounds served as a secondary sink of these bomb-derived 239,240Pu (31 ± 2% on average), and <20% of the 239,240Pu was immobilized by inorganic mineral particles. In a narrow, 239,240Pu-enriched layer of only 9-cm depth (total core depth was 600 cm), N-containing carboxyl aliphatic and/or alicyclic molecules (CCAM) in NOMFe-oxide and other NOM fractions immobilized the majority of 239,240Pu. Among the cluster of N-containing CCAM moieties, hydroxamate siderophores, the strongest known Pu chelators in nature, were further detected in these "aged" Nagasaki bomb residue-containing sediments. While present long-term disposal and environmental remediation modeling assume that solubility limits and sorption to mineral surfaces control Pu subsurface mobility, our observations suggest that NOM, which is present in essentially all subsurface systems, undoubtedly plays an important role in sequestrering Pu. Ignoring the role of NOM in controlling Pu fate and transport is not justified in most environmental systems.
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Affiliation(s)
- Peng Lin
- Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77553, United States.
| | - Chen Xu
- Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77553, United States
| | - Daniel I Kaplan
- Savannah River National Laboratory, Aiken, SC 29808, United States
| | - Hongmei Chen
- Department of Chemistry and Biochemistry, College of Sciences, Old Dominion University, Norfolk, VA 23529, United States
| | - Chris M Yeager
- Los Alamos National Laboratory, Los Alamos, NM 87545, United States
| | - Wei Xing
- Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77553, United States
| | - Luni Sun
- Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77553, United States
| | - Kathleen A Schwehr
- Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77553, United States
| | - Hideo Yamazaki
- Formally from Kindai University, Higashi-osaka, Osaka Prefecture 577-8502, Japan
| | - Yoko Saito-Kokubu
- Tono Geoscience Center, Japan Atomic Energy Agency, Jorinji, Izumicho, Toki-Shi, Gifu Prefecture 509-5102, Japan
| | - Patrick G Hatcher
- Department of Chemistry and Biochemistry, College of Sciences, Old Dominion University, Norfolk, VA 23529, United States
| | - Peter H Santschi
- Department of Marine Science, Texas A&M University at Galveston, Galveston, TX 77553, United States
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7
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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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8
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Ni Y, Wang Z, Zheng J, Tagami K, Guo Q, Uchida S, Tsukada H. The transfer of fallout plutonium from paddy soil to rice: A field study in Japan. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 196:22-28. [PMID: 30368198 DOI: 10.1016/j.jenvrad.2018.10.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 10/19/2018] [Accepted: 10/19/2018] [Indexed: 06/08/2023]
Abstract
Reported transfer factor (TF) values of Pu from paddy soil to rice are rather scarce, despite the radiotoxicity of Pu and the irreplaceable role of rice in Asian peoples' diets. Here, we conducted a field study to investigate the transfer of global fallout Pu from paddy soil to rice grain (hulled rice) in Japan. The 240Pu/239Pu atomic ratios in two rice grain samples out of 16 samples were determined and the ratios corresponded well with the global fallout value. The soil-to-rice TFPu in 12 Japanese prefectures ranged from 4.5 × 10-6 to 1.2 × 10-4 with a geometric mean of 3.3 × 10-5. The TFs of rice obtained in this study were compatible to the TFs for the broad heading "cereals" compiled in the IAEA Technical Report Series No. 472. Weak correlations were found between the TF and the investigated soil characteristics such as soil pH and loss on ignition. Regarding the TFs for cerium (Ce) and thorium (Th) which are commonly considered as Pu analogues, we observed no significant correlations between the log(TFPu) and log(TFCe) or log(TFPu) and log(TFTh). On the other hand, interestingly, a significantly positive correlation (r = 0.795, p < 0.001) was observed between log(TFPu) and log(TFU). In view of the observed similarity of TF values for U and Pu from soil to rice, we thought that using the easy-to-measure TFU to estimate TFPu from soil to rice might be suggested although the mechanism was unclear.
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Affiliation(s)
- Youyi Ni
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan; State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Zhongtang Wang
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Jian Zheng
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan.
| | - Keiko Tagami
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Qiuju Guo
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Shigeo Uchida
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, 263-8555, Japan
| | - Hirofumi Tsukada
- Institute of Environmental Radioecology, Fukushima University, 1 Kanayagawa, Fukushima, 960-1296, Japan
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Yamazaki H, Ishida M, Hinokio R, Yamashiki YA, Azuma R. Spatiotemporal distribution and fluctuation of radiocesium in Tokyo Bay in the five years following the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. PLoS One 2018; 13:e0193414. [PMID: 29494667 PMCID: PMC5832246 DOI: 10.1371/journal.pone.0193414] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 02/10/2018] [Indexed: 11/19/2022] Open
Abstract
A monitoring survey was conducted from August 2011 to July 2016 of the spatiotemporal distribution in the 400 km2 area of the northern part of Tokyo Bay and in rivers flowing into it of radiocesium released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. The average inventory in the river mouth (10 km2) was 131 kBq⋅m-2 and 0.73 kBq⋅m-2 in the central bay (330 km2) as the decay corrected value on March 16, 2011. Most of the radiocesium that flowed into Tokyo Bay originated in the northeastern section of the Tokyo metropolitan area, where the highest precipitation zone of 137Cs in soil was almost the same level as that in Fukushima City, then flowed into and was deposited in the Old-Edogawa River estuary, deep in Tokyo Bay. The highest precipitation of radiocesium measured in the high contaminated zone was 460 kBq⋅m-2. The inventory in sediment off the estuary of Old-Edogawa was 20.1 kBq⋅m-2 in August 2011 immediately after the accident, but it increased to 104 kBq⋅m-2 in July 2016. However, the radiocesium diffused minimally in sediments in the central area of Tokyo Bay in the five years following the FDNPP accident. The flux of radiocesium off the estuary decreased slightly immediately after the accident and conformed almost exactly to the values predicted based on its radioactive decay. Contrarily, the inventory of radiocesium in the sediment has increased. It was estimated that of the 8.33 TBq precipitated from the atmosphere in the catchment regions of the rivers Edogawa and Old-Edogawa, 1.31 TBq migrated through rivers and was deposited in the sediments of the Old-Edogawa estuary by July 2016. Currently, 0.25 TBq⋅yr-1 of radiocesium continues to flow into the deep parts of Tokyo Bay.
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Affiliation(s)
- Hideo Yamazaki
- Graduate School of Science and Engineering, Kindai University, Higashiosaka, Osaka, Japan
| | - Masanobu Ishida
- Graduate School of Science and Engineering, Kindai University, Higashiosaka, Osaka, Japan
- * E-mail:
| | - Ryoichi Hinokio
- Faculty of Science and Technology, Ryukoku University, Otsu, Shiga, Japan
| | - Yosuke Alexandre Yamashiki
- Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto University, Kyoto, Kyoto, Japan
| | - Ryokei Azuma
- Department of Civil Engineering and Urban Design, Osaka Institute of Technology, Osaka, Osaka, Japan
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10
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Automatic sequential separation with an anion-exchange column for ultra-trace analysis of Pu, U, Th, Pb, and lanthanides in environmental samples. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-016-4837-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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11
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Vrel A, Boust D, Lesueur P, Deloffre J, Dubrulle-Brunaud C, Solier L, Rozet M, Thouroude C, Cossonnet C, Thomas S. Dating of sediment record at two contrasting sites of the Seine River using radioactivity data and hydrological time series. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2013; 126:20-31. [PMID: 23933083 DOI: 10.1016/j.jenvrad.2013.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 06/06/2013] [Accepted: 06/17/2013] [Indexed: 06/02/2023]
Abstract
Sediment cores were collected at the outlet of the highly anthropogenized catchment of the Seine River at two contrasting sites: a flood plain of the lower Seine River and a quasi-permanently submerged harbour basin (or wet dock) in the upper tidal estuary. Analyses of artificial radionuclides ((137)Cs and plutonium isotopes), coupled with hydrological and bathymetric data, lead to a precise dating of the sediment cores collected at the two sites. (137)Cs signals originating from global fallout (early 1960s) and from the Chernobyl accident (1986) are identified, but at different levels due to the incomplete nature or variable continuity of the records. Anomalous (238)Pu concentrations found at both sites (1-2 Bq kg(-1)) are attributed to unknown industrial releases originating from upstream. Interpolating (137)Cs sediment activities under the assumption of a constant sediment rate, those releases were dated back to 1975 ± 1, thus providing a local but reliable time-marker. Age models have highlighted a very contrasting sediment filling dynamics in these two sites. This study presents the first sediment record of alpha- and gamma-emitting artificial radionuclides obtained at the outlet of the huge catchment area of the River Seine, over a period covering the last 50 years.
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Affiliation(s)
- Anne Vrel
- Laboratoire de Radioécologie de Cherbourg-Octeville (LRC), IRSN, 50130 Cherbourg-Octeville, France; Université de Caen-Basse Normandie, Laboratoire M2C, UMR CNRS 6143, 14032 Caen, France
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12
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Lindahl P, Andersen MB, Keith-Roach M, Worsfold P, Hyeong K, Choi MS, Lee SH. Spatial and temporal distribution of Pu in the Northwest Pacific Ocean using modern coral archives. ENVIRONMENT INTERNATIONAL 2012; 40:196-201. [PMID: 21890207 DOI: 10.1016/j.envint.2011.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 08/07/2011] [Accepted: 08/07/2011] [Indexed: 05/31/2023]
Abstract
Historical (239)Pu activity concentrations and (240)Pu/(239)Pu atom ratios were determined in skeletons of dated modern corals collected from three locations (Chuuk Lagoon, Ishigaki Island and Iki Island) to identify spatial and temporal variations in Pu inputs to the Northwest Pacific Ocean. The main Pu source in the Northwest Pacific is fallout from atmospheric nuclear weapons testing which consists of global fallout and close-in fallout from the former US Pacific Proving Grounds (PPG) in the Marshall Islands. PPG close-in fallout dominated the Pu input in the 1950s, as was observed with higher (240)Pu/(239)Pu atom ratios (>0.30) at the Ishigaki site. Specific fallout Pu contamination from the Nagasaki atomic bomb and the Ivy Mike thermonuclear detonation at the PPG were identified at Ishigaki Island from the (240)Pu/(239)Pu atom ratios of 0.07 and 0.46, respectively. During the 1960s and 1970s, global fallout was the major Pu source to the Northwest Pacific with over 60% contribution to the total Pu. After the cessation of the atmospheric nuclear tests, the PPG again dominated the Pu input due to the continuous transport of remobilised Pu from the Marshall Islands along the North Equatorial Current and the subsequent Kuroshio Current. The Pu contributions from the PPG in recent coral bands (1984 onwards) varied over time with average estimated PPG contributions between 54% and 72% depending on location.
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Affiliation(s)
- Patric Lindahl
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, UK; Marine Environment Research Department, Korea Ocean Research & Development Institute, 1270 Sadong, Ansan 426-744, South Korea.
| | - Morten B Andersen
- School of Earth Sciences, Bristol Isotope Group, University of Bristol, Wills Memorial Building, Bristol, BS8 1RJ, UK
| | - Miranda Keith-Roach
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, UK
| | - Paul Worsfold
- School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, UK
| | - Kiseong Hyeong
- Deep-Sea Resources Research Division, Korea Ocean Research & Development Institute, 1270 Sadong, Ansan 426-744, South Korea
| | - Min-Seok Choi
- Division of Earth and Environmental Science, Korea Basic Science Institute, 113 Gwahangno, Yusung-gu, Daejon 305-333, South Korea
| | - Sang-Hoon Lee
- Marine Geology and Geophysics Laboratory, Korea Ocean Research & Development Institute, 1270 Sadong, Ansan 426-744, South Korea
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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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Liu Z, Zheng J, Yamada M, Pan S, Kawahata H. Plutonium characteristics in sediments of Hiroshima Bay in the Seto Inland Sea in Japan. J Radioanal Nucl Chem 2011. [DOI: 10.1007/s10967-011-1025-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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