Radioactive pollution and accumulation of radionuclides in wild plants in Fukushima
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The radionuclide status of wild plants and soil in the Fukushima area was investigated during the period May 2011 to October 2012, using an imaging plate (autoradiograms) or a high purity germanium detector. Analyses of autoradiograms showed that wild plants grown in March 2011 were strongly polluted with fallout released from the Fukushima 1 Nuclear Power Plant. The radioactivity was mostly due to fallout adsorbed on the surface of the plants. On the other hand, a number of herbaceous plants were regularly collected in the Fukushima area and their radionuclide concentrations were measured with a high-purity germanium detector. Plants grown in March 2011 showed very high levels of 134Cs and 137Cs, but these radioactivity levels decreased rapidly after July 2011 and eventually became lower than that of endogenous 40K. During this period, the radioactivity of the soil remained high. We therefore suppose that a significant proportion of the radioactivity detected from plants harvested after July 2011 was most likely derived from soil dust attached on the plant surface. Autoradiograms of rice plants were virtually identical between plants cultivated in Fukushima and Osaka area, reflecting the background radiation due to 40K.
KeywordsContamination of wild plants 137Cs 134Cs Fukushima Daiichi Nuclear Power Plant Radionuclides
Fukushima 1 Nuclear Power Plant
We thank Mr. Toshiyasu Okochi, Family Ouchi and Ms. Kazumi Tsutsui for their kind permission to collect plant and soil samples from their fields. We are grateful to Dr. Robert Reid, The University of Adelaide, Australia, for his kind assistance with the English text. The present work was supported in part by a grant from the Mitsui & Co., Ltd. Environment Fund, a grant from Japan Society for the Promotion of Science and a grant from the Ministry of Education, Culture, Sports, Science and Technology of Japan (Grant-in-Aid no. 24110007).
- Inoue M, Kofuji H, Nagao S, Yamamoto M, Hamajima Y, Yoshida K, Fujimoto K, Takada T, Isoda Y (2012) Lateral variation of 134Cs and 137Cs concentrations in surface seawater in and around the Japan Sea after the Fukushima Dai-ichi Nuclear Power Plant accident. J Environ Radioact 109:45–51CrossRefPubMedGoogle Scholar
- International Atomic Energy Agency (IAEA), Fukushima Nuclear Accident, http://www.iaea.org/newscenter/focus/fukushima/. Accessed 26 Oct 2013
- Mimura T, Mimura M, Komiyama C, Miyamoto M, Kitamura A (2014) 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. J Plant Res 127 (in this issue). doi: 10.1007/s10265-013-0594-y
- Ministry of Agriculture, Forestry and Fisheries, The Great East Japan Earthquake (http://www.maff.go.jp/e/quake/press_110312-1.html). Accessed 26 Oct 2013
- Nuclear Regulation Authority (NRA), Monitoring information of environmental radioactivity level. http://radioactivity.nsr.go.jp/ja/index.html. Accessed 26 Oct 2013
- Sakamoto F, Ohnuki T, Kozai N, Igarashi S, Yamasaki S, Yoshida Z, Tanaka S (2012) Local distributions of radioactive Cs deposited on plant and soil from Fukushima Daiichi Nuclear Power Plants. Annual Report of ASRC (Advanced Science Research Center) 2011:7Google Scholar