Research Article

Concentration of Strontium-90 at Selected Hot Spots in Japan

• Georg Steinhauser mail,
  
  
• Viktoria Schauer,
• Katsumi Shozugawa  
•  

  Abstract

  This study is dedicated to the environmental monitoring of radionuclides released in the course of the Fukushima nuclear accident. The activity concentrations of β⁻ -emitting ⁹⁰Sr and β⁻/γ-emitting ¹³⁴Cs and ¹³⁷Cs from several hot spots in Japan were determined in soil and vegetation samples. The ⁹⁰Sr contamination levels of the samples were relatively low and did not exceed the Bq⋅g⁻¹ range. They were up four orders of magnitude lower than the respective ¹³⁷Cs levels. This study, therefore, experimentally confirms previous predictions indicating a low release of ⁹⁰Sr from the Fukushima reactors, due to its low volatility. The radiocesium contamination could be clearly attributed to the Fukushima nuclear accident via its activity ratio fingerprint (¹³⁴Cs/¹³⁷Cs). Although the correlation between ⁹⁰Sr and ¹³⁷Cs is relatively weak, the data set suggests an intrinsic coexistence of both radionuclides in the contaminations caused by the Fukushima nuclear accident. This observation is of great importance not only for remediation campaigns but also for the current food monitoring campaigns, which currently rely on the assumption that the activity concentrations of β⁻-emitting ⁹⁰Sr (which is relatively laborious to determine) is not higher than 10% of the level of γ-emitting ¹³⁷Cs (which can be measured quickly). This assumption could be confirmed for the samples investigated herein.
  Citation: Steinhauser G, Schauer V, Shozugawa K (2013) Concentration of Strontium-90 at Selected Hot Spots in Japan. PLoS ONE 8(3): e57760. doi:10.1371/journal.pone.0057760
  Editor: Christof Markus Aegerter, University of Zurich, Switzerland
  
  
  Citation: Steinhauser G, Schauer V, Shozugawa K (2013) Concentration of Strontium-90 at Selected Hot Spots in Japan. PLoS ONE 8(3): e57760. doi:10.1371/journal.pone.0057760
  Editor: Christof Markus Aegerter, University of Zurich, Switzerland
  Received: October 24, 2012; Accepted: January 24, 2013; Published: March 7, 2013
  Copyright: © 2013 Steinhauser 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.
  Funding: Partial funding of this work by the Austrian Federal Ministry for Agriculture, Forestry, Environment and Water Management (BMLFUW) and the Dr. Michael-Häupl-Fonds is gratefully acknowledged. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
  Competing interests: The authors have declared that no competing interests exist.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0057760#s4