Journal of Plant Research

, Volume 127, Issue 1, pp 91–97 | Cite as

Measurements of gamma (γ)-emitting radionuclides with a high-purity germanium detector: the methods and reliability of our environmental assessments on the Fukushima 1 Nuclear Power Plant accident

  • Tetsuro MimuraEmail author
  • Mari Mimura
  • Chiyo Komiyama
  • Masaaki Miyamoto
  • Akira Kitamura
JPR Symposium Current status and future control of cesium contamination in plants and algae in Fukushima


The severe accident of Fukushima 1 Nuclear Power Plant due to the Tohoku Region Pacific Coast Earthquake in 11 March 2011 caused wide contamination and pollution by radionuclides in Fukushima and surrounding prefectures. In the current JPR symposium, a group of plant scientists attempted to examine the impact of the radioactive contamination on wild and cultivated plants. Measurements of gamma (γ) radiation from radionuclides in “Fukushima samples”, which we called and collected from natural and agricultural areas in Fukushima prefecture were mostly done with a high-purity Ge detector in the Graduate School of Maritime Sciences, Kobe University. In this technical note, we describe the methods of sample preparation and measurements of radioactivity of the samples and discuss the reliability of our data in regards to the International Atomic Energy Agency (IAEA) Interlaboratory comparisons and proficiency test (IAEA proficiency test).


A high-purity Ge semiconductor detector 137Cs 134Cs Fukushima 1 Nuclear Power Plant IAEA proficiency test Radionuclides 



Fukushma 1 Nucelar Power Plant


International Atomic Energy Agency


High-purity germanium


Multi-channel analyzer


Counts per second


Gamma-ray counts per second



The new multi-channel analyzer and data analysis software were purchased by the emergent financial support from Kobe University. We are grateful to Prof. Yuichi Onda (University of Tsukuba) for his kind support for using the set of standards for preliminary calibration of the detector and joining the IAEA proficiency test. We are also grateful to the laboratories participating in the ad-hoc measurement group organized by Prof. Kazuyoshi Masumoto and Michihiro Shibata, Japanese Society of Radiation Safety Management, for providing the standard set of U8 samples for calibration. We thank Prof. Keiji Oda, Prof. Tomoya Yamauchi, Prof. Hideo Okamura and Dr. Yuji Tooyama for their assistance with the use of the HPGe detector, and also IAEA for evaluation of our measurements in the proficiency test. We are grateful to Dr. Robert Reid, The University of Adelaide, Australia, for his kind assistance with the English text. The present technical work was partly supported by a grant from the Mitsui & Co., Ltd. Environment Fund and Grant-in-Aid for Scientific Research on Innovative Areas Grant Number 24110007.


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Copyright information

© The Botanical Society of Japan and Springer Japan 2013

Authors and Affiliations

  • Tetsuro Mimura
    • 1
    Email author
  • Mari Mimura
    • 1
  • Chiyo Komiyama
    • 2
  • Masaaki Miyamoto
    • 3
  • Akira Kitamura
    • 2
  1. 1.Department of Biology, Graduate School of ScienceKobe UniversityKobeJapan
  2. 2.Department of Marine Engineering, Graduate School of Maritime SciencesKobe UniversityKobeJapan
  3. 3.Radioisotope Division, Center for Supports to Research and Educational ActivitiesKobe UniversityKobeJapan

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