Investigation on the influence of rivers by biological samples and depth distribution measurement

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K08700
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Medical Physics and Radiological Technology
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: FUKUSHI MASAHIRO 首都大学東京, 人間健康科学研究科, 教授 (70199199)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: モクズガニ / 放射性セシウム濃度

Outline of Final Research Achievements

I conducted a survey on Biological condensation of radioactive caesium at Tomioka River etc. in Fukushima Prefecture. The eriocheir japonica shell inhabiting the Tomioka River has a relatively high radioactive cesium concentration. The shell of eriocheir japonica was dried and crushed and measured with High purity germanium semiconductor detector. In addition, Soil depth contamination distribution was measured with portable radiation depth distribution spectrometer. As a result, the Cs - 137 concentration of the eriocheir japonica shell in the Tomioka River changed from 299 ± 3.71 Bq / kg (2015), 232 ± 2.63 Bq / kg (2016) and 110 ± 3.06 Bq / kg (2017). Other rivers also showed a similar trend. The concentration of Cs-137 in river water was not detected. In soil depth contamination distribution, contaminated soil was deeper than the surface layer.
From these results, the Biological condensation of organisms was found out. I think that investigation is necessary in the future.

Free Research Field

医学物理学