Department of Radiochemistry and Radioecology

Research Overview

 The Department of Radiochemistry and Radioecology carries out chemical approaches to evaluate radiation exposure doses. Studies evaluate internal exposure doses from radioactive materials are carried out. Intake, residual, and excretion amounts in the human body are evaluated by analyzing radionuclides in a biological sample. In addition, analysis of radionuclide concentration in the environment and understanding environmental dynamics are important in the evaluation of exposure dose. To do so, analysis of environmental samples is also carried out. Hirosaki University has been designated as an Advance Medical Care for Radiation Exposure Support Center and a Nuclear Disaster Medical Care / General Support Center by the Nuclear Regulatory Commission.
This laboratory is in charge of internal exposure dose evaluations including actinide by bioassay by the Advance Medical Care for Radiation Exposure Support Center.

Current Research Themes

  1. Development of analytical methods for radioactive material in biological samples and study on the evaluation of internal exposure doses
  2. Study of tritium measurement in environmental and biological samples
  3. Distribution and behavior of radionuclides in Fukushima Prefecture
  4. Earth science study using tritium and cosmogenic radionuclides as a tracer
  5. Environmental chemistry using stable and radioactive isotopes

Laboratory Organization

  • • Professor Naofumi Akata
  • • Assistant Professor Yamada Ryohei
  • • Technical Assistant Haruka Kuwata (Master’s program, 2nd year)
  • • Student Khemruthai Kheamsiri (Master’s program, 2nd year)
  • • Visiting Researcher Akira Takeda (Institute for Environmental Sciences, Japan)
  • • Visiting Researcher Yusuke Unno (Institute for Environmental Sciences, Japan)
  • • Visiting Researcher Mathew Swallow(Mount Royal University, Canada)
  • • Visiting Researcher Hideki Kimura


Germanium semiconductor detector Tritium electrical enrichment system

Recent Projects

  • • Grants-in-Aid for Scientific Research (B),  Establishment of simple and high precision method for environmental tritium measurement and its background concentration measurement in Japan (2021-2025) (Principal Investigator)
  • • Challenging Research (Exploratory), A revised interpretation of the relationship between d18O in snow and surface temperature over Antarctica (2018-2021) (research contributor)
  • • National Institute for Fusion Science LHD Project Collaborative Research, Development of Field Estimation Technique and Improvement of Environmental Tritium Behavior Model (2018-2021) (research contributor)
  • • Grants-in-Aid for Scientific Research (B), Elucidation of the movement of a dynamic hydrogen isotope by the mid-infrared laser spectroscopy (2018-2021) (research contributor)
  • • Fund for the Promotion of Joint International Research (Fostering Joint International Research), Study of the multi-isotope method to trace study of the natural tritium (2018-2021) (Principal Investigator)
  • • Grants-in-Aid for Scientific Research (C), Development of high time resolution atmospheric tritium sampler and its application as environmental research (2017-2021) (Principal Investigator),
  • • Grants-in-Aid for Scientific Research (C),  Pretreatment Technique for Environmental Tritium Analysis with Microwave Heating Method (2014-2017) (Principal Investigator),

Recent research results

  • • Naofumi Akata, Hideki Kakiuchi, Masahiro Tanaka, Yoshio Ishikawa, Naoyuki Kurita, Masahide Furukawa, Miklos Hegedus, Tibor Kovacs, Maksym Gusyev, Tetsuya Sanada, Isotope and chemical composition of monthly precipitation collected at Sapporo, northern part of Japan during 2015-2019, Fusion Engineering and Design, 168, 112434(2021)
  • • Naofumi Akata, Chie Iwata, Miki Nakada, Masahiro Tanaka, Hideki Kakiuchi, Tibor Kovacs, Fumitaka, Yanagisawa, Yutaka Kanai, Characterization of atmospheric 210Pb concentration and its relation to major ion species at Tsukuba, Japan, Journal of Radioanalytical and Nuclear Chemistry, 327, 755-760(2021)

Characteristics of the Laboratory

We are promoting the radiochemistry and radioecology with internal dose assessment as the main theme.