Application of lichens to evaluate distribution of radionuclides nearby the Fukushima Dai-ichi Nuclear Power Station

Dohi, Terumi   ; Iijima, Kazuki  ; Omura, Yoshihito*; Fujiwara, Kenso ; Kikuchi, Naoyuki*

The local radioactive contaminations (i.e. radioactive plume's trace) around the FDNPS were caused by the releasing radionuclides from each reactor, weather conditions, etc. Japan Atomic Energy Agency is carrying out the project to evaluate off-site distribution of radionuclides and to determine the origin of plume's traces at each point, since we develop the model to estimate on-site distribution. As lichens are known to be effective tools to monitor environmental radionuclides in both time and space because of their ability to retain radionuclides for a long period, lichen samples are expected to be used to examine initial fallout distribution. The purpose of this study is to measure radionuclides concentrations in lichens and analyse elemental composition in particles captured on lichen thalli, in order to evaluate initial distribution of radionuclides and clarify the contamination characteristics of the plume's traces nearby the FDNPS.