October 31, 2022 The 6th IER seminar was held. 〈Professor Tsukada, Associate Professors Hirao and Wakiyama〉

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

In the 6th IER seminar of this fiscal year that held on October 31, 2022, three researchers gave presentations on their research activities and results. The seminar was attended by 23 researchers and students.

Prof. Hirao presented his research on atmospheric HTO concentration. In the presentation, he showed the variation of HTO concentration obtained from investigations conducted around the FDNPP, and explained the causes of these variations along with the variations in environmental factors such as wind direction and speed.

Prof. Tsukada presented about activity concentration of ¹²⁹I and ¹³⁷Cs in crops and internal radiation exposure from self-consumed crops and wild edible plants (wild vegetables, fruits, etc.) in the difficult-to-return zone. As for the first topic, he explained that although ¹²⁹I derived from the nuclear accident was detected in Fukushima by investigations, the calculated internal exposure is extremely low. For the other topic, he showed that although ¹³⁷Cs concentration exceeding the standard level was detected in some wild plants, the effects on internal exposure were small.

Prof. Wakiyama presented the results of his research on the Niida River, which flows through the northern part of Hamadori area, regarding the impact of nearby decontamination activities on the dynamics of ¹³⁷Cs in the river. He also presented the analytical results of samples collected during high-flow events.

After the presentations, participants gave the presenters various questions and comments, and they had a fruitful discussion.