October 25, 2021 We held the 6th IER Seminar of FY2021.＜by Prof. TSUKADA＞

Institute of Environmental Radioactivity (IER) regularly holds the IER seminar, in which the faculty members report on their research results, with the purpose of facilitating their research activities and communication.

The 6th IER Seminar of FY2021 was held on October 25, and Professor Hirofumi Tsukada gave a presentation on his research activities. The seminar was attended by 15 researchers and graduate students, including online attendees.

Prof. Tsukada’s field of research is environmental radioecology and he has been especially conducting researches on the speciation of radionuclides in soil. In the seminar, he introduced a new approach called “Density fractionation”, which is used to separate and quantify rediocaesium according to its state in soil, and talked about the results obtained using this method.

Using this method, it was found that most of the radiocaesium derived from the Fukushima Dai-ichi Nuclear Power Plant accident was contained in the heavy fraction, which is dominated by minerals, but accumulated at higher concentrations in the middle fraction where includes relatively decomposed organic matters associated with minerals than in other fractions.

After the presentation, the participants gave Prof. Tsukada specific questions such as if the methodology can be used for forest soils.