On March 18, 2025, Professors TSUKADA Hirofumi and Aleksei KONOPLEV delivered their final lectures.

Date & Time	Tue. March 18, 2025, 13:30 ‒ 16:30 JST
Venue	6F Conference Room, Main Bldg. IER/Online (Zoom)
Lecturers	Professor TSUKADA Hirofumi Project Professor Aleksei KONOPLEV (Vice Director) (Presentation order)
Lecture Titles	From Geochemistry to Environmental Radioecology —Interpretation of environmental radioactivity dynamics utilizing speciation and specific radioactivity— (Tsukada) The way of scientist: from upper atmosphere via Chornobyl to Fukushima (Konoplev)

The final lectures by Professors TSUKADA Hirofumi and Aleksei KONOPLEV, who are retiring at the end of the academic year of 2024, were attended in person by approximately 80 people, including researchers, graduate students, alumni, the general public, and faculty and staff, while about 90 people joined online.

Professor Tsukada, after graduating from the School of Fisheries Sciences at Hokkaido University, honed his expertise in environmental radioecology at the Institute for Environmental Sciences. In 2001, he obtained his doctoral degree (PhD in Agriculture) from the Graduate School of Agricultural Science at Tohoku University. In April 2014, he joined the Institute of Environmental Radioactivity (IER) as a professor, teaching at the university’s graduate school while also serving as the director of IER, contributing significantly to the institute’s operations.

In his final lecture, titled “From Geochemistry to Environmental Radioecology,” he shared the achievements of his research and discussed the importance of new research approaches, such as predicting activity concentrations of radionuclides in crops.

The lecture offered a meaningful opportunity to experience the passion of Professor Tsukada, who has dedicated himself to the restoration of agriculture in Fukushima.

Project Professor Alexei Konoplev graduated from the Faculty of Chemistry at Moscow State University and spent 36 years at Research Production Association “Typhoon,” a leading institute in the field of environmental monitoring at the time. He obtained his PhD (Кандидат наук) in Chemistry in 1983, and then he earned his Doctor of Science (Доктор наук) in Radiobiology in 1998 after his academic achievement. In November 2013, he joined IER as a project professor. Over the years, he has taught at the university’s graduate school and served as a professor, and the vice director of IER.

In his final lecture, titled “The way of scientist: from upper atmosphere via Chornobyl and Fukushima,” he reflected on his research journey and discussed his findings from Fukushima, including how radioactive cesium in Fukushima strongly binds to soil and sediments, making its bioavailability to plants and biota relatively low.

During the Q&A session following the lectures, a warm atmosphere filled the venue, with smiles shared naturally between the professors and attendees.

A celebration party was held in the evening, where everyone engaged in conversation and enjoyed the friendly atmosphere.

We extend our heartfelt gratitude to Professors Tsukada and Konoplev for their many years of dedication to education and research.