Loss of #radioactivity in #radiocesium-bearing #microparticles emitted from the #Fukushima Dai-ichi #NPP by heating (Sci Rep., abstract)

[Source: Scientific Reports, full page: (LINK). Abstract, edited.]

Article | OPEN | Published: 26 June 2018

Loss of radioactivity in radiocesium-bearing microparticles emitted from the Fukushima Dai-ichi nuclear power plant by heating

Taiga Okumura, Noriko Yamaguchi, Terumi Dohi, Kazuki Iijima & Toshihiro Kogure

Scientific Reports, volume 8, Article number: 9707 (2018)

 

Abstract

Radiocesium-bearing microparticles (CsPs) substantially made of silicate glass are a novel form of radiocesium emitted from the broken containment vessel of Fukushima Dai-ichi nuclear power plant. CsPs have a potential risk of internal radiation exposure caused by inhalation. Radiation-contaminated waste including CsPs is being burned in incinerators; therefore, this study has investigated the responses of CsPs to heating in air. The radioactivity of CsPs gradually decreased from 600 °C and was almost lost when the temperature reached 1000 °C. The size and spherical morphology of CsPs were almost unchanged after heating, but cesium including radiocesium, potassium and chlorine were lost, probably diffused away from the CsPs. Iron, zinc and tin originally dissolved in the glass matrix were crystallized to oxide nanoparticles inside the CsPs. When the CsPs were heated together with weathered granitic soil that is common in Fukushima, the radiocesium released from CsPs was sorbed by the surrounding soil. From these results, it is expected that the radioactivity of CsPs will be lost when radiation-contaminated waste including CsPs is burned in incinerators.

Keywords: Radiations; Nuclear Events; Environmental Pollution.

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Spatiotemporal #distribution and #fluctuation of #radiocesium in #Tokyo Bay in the five years following the #Fukushima Daiichi Nuclear Power Plant (FDNPP) accident (PLoS One, abstract)

[Source: PLoS One, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Spatiotemporal distribution and fluctuation of radiocesium in Tokyo Bay in the five years following the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident

Hideo Yamazaki, Masanobu Ishida , Ryoichi Hinokio, Yosuke Alexandre Yamashiki, Ryokei Azuma

Published: March 1, 2018 / DOI: https://doi.org/10.1371/journal.pone.0193414

 

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-2in 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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Citation: Yamazaki H, Ishida M, Hinokio R, Yamashiki YA, Azuma R (2018) Spatiotemporal distribution and fluctuation of radiocesium in Tokyo Bay in the five years following the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. PLoS ONE 13(3): e0193414. https://doi.org/10.1371/journal.pone.0193414

Editor: Tim A. Mousseau, University of South Carolina, UNITED STATES

Received: November 16, 2017; Accepted: February 10, 2018; Published: March 1, 2018

Copyright: © 2018 Yamazaki et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: Relevant data are within the paper and its Supporting Information files. The radiocesium activity of global fallout data are available from the Japan Chemical Analysis Center (JCAC), found here: http://www.kankyo-hoshano.go.jp/en/07/07.html.

Funding: This work was supported by the following: Grant number: 24310014 (HY), https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-24310014/. Principal investigator is Hideo Yamazaki. He plays roles in Conceptualization, Investigation, Writing – Review & Editing. Grant number: 26289155 (HY, RA), https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-26289155/. Co-investigators are Hideo Yamazaki and Ryokei Azuma. Ryokei Azuma plays a role in Formal Analysis. Grant number: 15J10109 (MI), https://www.jsps.go.jp/j-pd/data/saiyo_ichiran/h27/dc1/h27_dc1_09_sougou.pdf [in Japanese]. The URL is described the adopters for JSPS DC1; Under the URL, the overview of DC1 is described; https://www.jsps.go.jp/english/e-pd/index.html. Principal investigator is Masanobu Ishida. He plays roles in Data Curation, Formal Analysis, Investigation, Methodology, Project Administration, Visualization and Writing – Original Draft Preparation. Grant number: 26303004 (RA, HY), https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-26303004/. Principal investigator is Ryokei Azuma. Co-investigator is Hideo Yamazaki. Grant number: 24110006 (YY), https://kaken.nii.ac.jp/en/grant/KAKENHI-PLANNED-24110006/. Co-investigator is Yosuke Yamashiki. He plays a role in Formal Analysis and Investigation.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Japan; Nuclear Events; Environmental Pollution; Radiations.

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Electron spin resonance (#ESR) dose #measurement in #bone of #Hiroshima #Atomic #bomb #victim (PLoS One, abstract)

[Source: PLoS One, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Electron spin resonance (ESR) dose measurement in bone of Hiroshima A-bomb victim

Angela Kinoshita  , Oswaldo Baffa , Sérgio Mascarenhas

Published: February 6, 2018 / DOI: https://doi.org/10.1371/journal.pone.0192444

 

Abstract

Explosion of the bombs in Hiroshima and Nagasaki corresponds to the only historical moment when atomic bombs were used against civilians. This event triggered countless investigations into the effects and dosimetry of ionizing radiation. However, none of the investigations has used the victims’ bones as dosimeter. Here, we assess samples of bones obtained from fatal victims of the explosion by Electron Spin Resonance (ESR). In 1973, one of the authors of the present study (SM) traveled to Japan and conducted a preliminary experiment on the victims’ bone samples. The idea was to use the paramagnetism induced in bone after irradiation to measure the radiation dose. Technological advances involved in the construction of spectrometers, better knowledge of the paramagnetic center, and improvement in signal processing techniques have allowed us to resume the investigation. We obtained a reconstructed dose of 9.46 ± 3.4 Gy from the jawbone, which was compatible with the dose distribution in different locations as measured in non-biological materials such as wall bricks and roof tiles.

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Citation: Kinoshita A, Baffa O, Mascarenhas S (2018) Electron spin resonance (ESR) dose measurement in bone of Hiroshima A-bomb victim. PLoS ONE 13(2): e0192444. https://doi.org/10.1371/journal.pone.0192444

Editor: Sergey Sholom, Oklahoma State University Stillwater, UNITED STATES

Received: July 3, 2017; Accepted: January 11, 2018; Published: February 6, 2018

Copyright: © 2018 Kinoshita et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the paper.

Funding: The authors received no specific funding for this work.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Nuclear Events; Radiations; Japan.

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Analysis of #heteroplasmy in bank #voles inhabiting the #Chernobyl exclusion zone: A commentary on Baker et al. (2017) “Elevated mitochondrial genome variation after 50 generations of radiation exposure in a wild rodent.” (Evol Appl., abstract)

[Source: Evolutionary Applications, full page: (LINK). Abstract, edited.]

Evolutionary Applications. 2017;1–7.

Received: 9 October 2017  – Accepted: 3 November 2017

DOI: 10.1111/eva.12578

Analysis of heteroplasmy in bank voles inhabiting the Chernobyl exclusion zone: A commentary on Baker et al. (2017) “Elevated mitochondrial genome variation after 50 generations of radiation exposure in a wild rodent.”

Jenni Kesäniemi 1, Zbyszek Boratyński 2, John Danforth 1, Prince Itam 1, Toni Jernfors 1,
Anton Lavrinienko 1, Tapio Mappes 3, Anders Pape Møller 4,  Timothy A. Mousseau 5, Phillip C. Watts 1

1 Department of Ecology and Genetics, University of Oulu, Oulu, Finland;  2 CIBIO/InBIO, Research Center in Biodiversity and Genetic Resources, University of Porto, Vairão, Portugal; 3 Department of Biological and Environmental Science, University of Jyväskylä,  Jyväskylä, Finland; 4 Ecologie Systématique Evolution, Universit é Paris-Sud, CNRS, AgroParisTech, Universit é Paris-Saclay, Orsay Cedex, France; 5 Department of Biological Sciences, University of South Carolina, Columbia, SC, USA

Correspondence: Jenni Kesäniemi, Department of Ecology and Genetics, University of Oulu, Oulu, Finland. Email: jenni.kesaniemi@oulu.fi

Funding information: Academy of Finland, Grant/Award Number: PCW:287153 and  TM:268670

KEYWORDS: ecological genetics, molecular evolution, population ecology

 

INTRODUCTION

Exposure  to ionizing  radiation  is a well- established  cause of mutation.  Given the global problem of accidental release of radionuclides into the environment (Lourenço,
Mendo, & Pereira, 2016), it is essential to fully understand the genetic consequences of exposure to radio-nuclides.  On 26 April 1986, a fire and explosion in Reactor 4 of the former nuclear power plant at Chernobyl (CNPP), Ukraine, released more than 9 million terabecquerels (TBq) of radionuclides over much (>200,000 km 2) of Europe and eastern Russia (see reviews on the ef fects, e.g., Mousseau & Møller, 2012; Møller & Mousseau, 2006). The Chernobyl Exclusion Zone (CEZ) was established at about a 30- km radius around the accident site to limit human exposure to radioactive fallout. The CEZ contains elevated levels of persistent radioisotopes, notably strontium- 90 (90S), caesium-137 (137
Cs) and plutonium- 239 (239Pu) that have half- lives of 28.8, 30.2 and 24,100 years, respectively. Wildlife inhabiting the CEZ provide clear models of the biological consequences of exposure to environmental radionuclides, with many reports of elevated levels of developmental instability, genetic damage and mutation rate associated with inhabiting areas contaminated by radionuclides. Hence, a meta- analysis revealed a strong effect of radiation upon mutation rate in organisms affected by Chernobyl fallout (data for 30 species in 45 published studies) (Møller & Mousseau, 2015). With this in mind, the report by Baker et al. (2017) in Evolutionary Applications of elevated levels of genetic diversity rates in bank voles inhabiting the CEZ appears consistent with the putative mutagenic effect ofexposure to radionuclides (…)

Keywords: Nuclear Events; Environmental Disasters; European Region.

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Unexpected #source of #Fukushima-derived #radiocesium to the coastal #ocean of #Japan (Proc Natl Acad Sci USA, abstract)

[Source: Proceedings of the National Academy of Sciences of the United States of America, full page: (LINK). Abstract, edited.]

Unexpected source of Fukushima-derived radiocesium to the coastal ocean of Japan

Virginie Sanial a,1, Ken O. Buesseler a,1, Matthew A. Charette a, and Seiya Nagao b

Author Affiliations: a Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543; b Low Level Radioactivity Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Kanazawa 920-1192, Japan

Edited by David M. Karl, University of Hawaii, Honolulu, HI, and approved August 28, 2017 (received for review May 24, 2017)

 

Significance

Five years after the Fukushima Dai-ichi Nuclear Power Plant accident, the highest radiocesium (137Cs) activities outside of the power plant site were observed in brackish groundwater underneath sand beaches. We hypothesize that the radiocesium was deposited on mineral surfaces in the days and weeks after the accident through wave- and tide-driven exchange of seawater through the beach face. As seawater radiocesium concentrations decreased, this radiocesium reentered the ocean via submarine groundwater discharge, at a rate on par with direct discharge from the power plant and river runoff. This new unanticipated pathway for the storage and release of radionuclides to ocean should be taken into account in the management of coastal areas where nuclear power plants are situated.

 

Abstract

There are 440 operational nuclear reactors in the world, with approximately one-half situated along the coastline. This includes the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), which experienced multiple reactor meltdowns in March 2011 followed by the release of radioactivity to the marine environment. While surface inputs to the ocean via atmospheric deposition and rivers are usually well monitored after a nuclear accident, no study has focused on subterranean pathways. During our study period, we found the highest cesium-137 (137Cs) levels (up to 23,000 Bq⋅m−3) outside of the FDNPP site not in the ocean, rivers, or potable groundwater, but in groundwater beneath sand beaches over tens of kilometers away from the FDNPP. Here, we present evidence of a previously unknown, ongoing source of Fukushima-derived 137Cs to the coastal ocean. We postulate that these beach sands were contaminated in 2011 through wave- and tide-driven exchange and sorption of highly radioactive Cs from seawater. Subsequent desorption of 137Cs and fluid exchange from the beach sands was quantified using naturally occurring radium isotopes. This estimated ocean 137Cs source (0.6 TBq⋅y−1) is of similar magnitude as the ongoing releases of 137Cs from the FDNPP site for 2013–2016, as well as the input of Fukushima-derived dissolved 137Cs via rivers. Although this ongoing source is not at present a public health issue for Japan, the release of Cs of this type and scale needs to be considered in nuclear power plant monitoring and scenarios involving future accidents.

Fukushima Dai-ichi Nuclear Power Plant accident –  cesium –  submarine groundwater discharge – radioactivity –  radium

 

Footnotes

1 To whom correspondence may be addressed. Email: kbuesseler@whoi.edu or virginie.sanial.vs@gmail.com.

Author contributions: K.O.B. and M.A.C. designed research; V.S., K.O.B., M.A.C., and S.N. performed research; V.S., K.O.B., M.A.C., and S.N. analyzed data; and V.S., K.O.B., M.A.C., and S.N. wrote the paper.

Conflict of interest statement: K.O.B. has served in a consulting capacity related to radionuclides in Japanese fisheries products.

This article is a PNAS Direct Submission.

This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1708659114/-/DCSupplemental.

Freely available online through the PNAS open access option.

Keywords: Environmental Pollution; Environmental Disasters; Nuclear Events; Japan; Radiations.

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#Dynamics and early post- #tsunami #evolution of floating marine #debris near #Fukushima Daiichi (Nat Geosci., abstract)

[Source: Nature Geoscience, full page: (LINK). Abstract, edited.]

Dynamics and early post-tsunami evolution of floating marine debris near Fukushima DaiichiDynamics and early post-tsunami evolution of floating marine debris near Fukushima Daiichi

John Philip Matthews, Lev Ostrovsky, Yutaka Yoshikawa, Satoru Komori & Hitoshi Tamura

Nature Geoscience (2017) / doi:10.1038/ngeo2975

Received 23 February 2017 – Accepted 23 May 2017 – Published online 03 July 2017

 

Abstract

The devastating tsunami triggered by the Tōhoku-Oki earthquake of 11 March 2011 caused a crisis at the Fukushima Daiichi nuclear power station where it overtopped the seawall defences. On retreating, the tsunami carried loose debris and wreckage seaward and marshalled buoyant material into extensive plumes. Widespread concern over the fate of these and numerous other Tōhoku tsunami depositions prompted attempts to simulate debris dispersion throughout the wider Pacific. However, the effects of locally perturbed wind and wave fields, active Langmuir circulation and current-induced attrition determine a complex and poorly understood morphology for large floating agglomerations. Here we show that the early post-tsunami evolution of marine-debris plumes near Fukushima Daiichi was also shaped by near-surface wind modifications that took place above relatively calm (lower surface roughness) waters covered by surface films derived from oil and other contaminants. High-spatial-resolution satellite tracking reveals faster-than-expected floating-debris motions and invigorated plume evolution within these regions, while numerical modelling of turbulent air flow over the low-drag, film-covered surface predicts typically metre-per-second wind strengthening at centimetric heights, sufficient to explain the observed debris-speed increases. Wind restructuring probably stimulates the dispersion of flotsam from both biological and anthropogenic sources throughout a global ocean of highly variable surface roughness.

Keywords: Tsunami; Earthquakes; Japan; Nuclear Events; Environmental Disasters; Environmental Pollution.

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Quantitative modeling of responses to chronic ionizing #radiation #exposure using targeted and non-targeted effects (PLoS One, abstract)

[Source: PLoS One, full page: (LINK). Abstract, edited.]

OPEN ACCESS / PEER-REVIEWED / RESEARCH ARTICLE

Quantitative modeling of responses to chronic ionizing radiation exposure using targeted and non-targeted effects

Igor Shuryak

Published: April 25, 2017 / https://doi.org/10.1371/journal.pone.0176476

 

Abstract

The biological effects of chronic ionizing radiation exposure can be difficult to study, but important to understand in order to protect the health of occupationally-exposed persons and victims of radiological accidents or malicious events. They include targeted effects (TE) caused by ionizations within/close to nuclear DNA, and non-targeted effects (NTE) caused by damage to other cell structures and/or activation of stress-signaling pathways in distant cells. Data on radiation damage in animal populations exposed over multiple generations to wide ranges of dose rates after the Chernobyl nuclear-power-plant accident are very useful for enhancing our understanding of these processes. We used a mechanistically-motivated mathematical model which includes TE and NTE to analyze a large published data set on chromosomal aberrations in pond snail (Lymnaea stagnalis) embryos collected over 16 years from water bodies contaminated by Chernobyl fallout, and from control locations. The fraction of embryo cells with aberrations increased dramatically (>10-fold) and non-linearly over a dose rate range of 0.03–420 μGy/h (0.00026–3.7 Gy/year). NTE were very important for describing the non-linearity of this radiation response: the TE-only model (without NTE) performed dramatically worse than the TE+NTE model. NTE were predicted to reach ½ of maximal intensity at 2.5 μGy/h (0.022 Gy/year) and to contribute >90% to the radiation response slope at dose rates <11 μGy/h (0.1 Gy/year). Internally-incorporated 90Sr was possibly more effective per unit dose than other radionuclides. The radiation response shape for chromosomal aberrations in snail embryos was consistent with data for a different endpoint: the fraction of young amoebocytes in adult snail haemolymph. Therefore, radiation may affect different snail life stages by similar mechanisms. The importance of NTE in our model-based analysis suggests that the search for modulators of NTE-related signaling pathways could be a promising strategy for mitigating the deleterious effects of chronic irradiation.

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Citation: Shuryak I (2017) Quantitative modeling of responses to chronic ionizing radiation exposure using targeted and non-targeted effects. PLoS ONE 12(4): e0176476. https://doi.org/10.1371/journal.pone.0176476

Editor: Roberto Amendola, ENEA Centro Ricerche Casaccia, ITALY

Received: November 1, 2016; Accepted: April 11, 2017; Published: April 25, 2017

Copyright: © 2017 Igor Shuryak. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: Data are available in supplementary materials.

Funding: The authors received no specific funding for this work.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Radiations; Environmental Pollution.

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