Current Issue

Radiation Environment and Medicine
Vol.11, No.2

Radiation Environment and Medicine Vol.11 No.2 cover
  • Publisher : Hirosaki University Press
  • Language : English
  • ISSN : 2423-9097 , 2432-163X
  • Release : August, 2022
  • Issue : Hirosaki University Press
  • pp. 41-103

Foreword

On the Occasion of the Publication of a New Journal
“Radiation Environment and Medicine”

I am privileged with the honor of sending my short message on the occasion of the publication by Hirosaki University Press of a new journal “Radiation Environment and Medicine”. This journal was previously published under the other title, “Radiation Emergency Medicine”, from 2012 through 2015 concurrently with the inauguration of the program to foster human resources in radiation emergency medicine that was approved by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan in 2010. This success is greatly indebted to the enthusiasm of the then President of Hirosaki University, Dr. Masahiko Endo, who firmly believed the necessity of establishing a stronghold on radiation emergency medicine in the northern region of Japan.

Having been launched by the Ex-President Dr. Masahiko Endo and continuously supported by the present President Dr. Kei Sato, the program has been run steadily by efforts of faculty members and students of Hirosaki University. Thereby, the publication of the journal overcame start-up problems and recently the Editorial Board discussed how to further upgrade the journal. In order to invite more submissions of papers, the Editorial Board decided to broaden the scope of the journal by incorporating “radiation environmental issues”. Thus, the journal wasrelabeled as “Radiation Environment and Medicine.”

I sincerely hope that not only domestic but also world-wide researchers in the related fields will contribute their scientific outcomes to the new journal.

Akihiro Shima, Ph.D.
Professor Emeritus, The University of Tokyo
Ex-Member of the External Evaluation Board of the Program


Preface

Hirosaki University has issued Radiation Emergency Medicine (REM) since 2012. An educational program for professionals in Radiation Emergency Medicine was initiated in 2010, and our prompt response to the Fukushima nuclear accident which occurred in 2011 motivated the publication of this journal. Many prestigious scientists from not only Japan, but also foreign countries have contributed to REM thus far.

In addition, the inaugural symposium was held in February 2012, with a focus on natural radiation exposures and low-dose radiation epidemiological studies (NARE2012). The symposium attracted more than 150 participants from 30 countries. Additionally, the ninth symposium in the series of international symposia on Natural Radiation Environment (NRE9), which commenced in the 1960s, was held in September 2014. A special session on the Fukushima nuclear accident was also included in the symposium. Approximately 200 participants from 35 countries attended NRE9. According to these two large symposia, many scientists in the world now recognize Hirosaki University as one of the prominent Japanese institutions, whose faculty conduct research on a wide spectrum of radiation topics.

Last August (2015), the Nuclear Regulation Authority designated Hirosaki University as having two important centers which cover radiation emergency medicine and radiation emergency medical assistance. In addition to these domestic situations, there have been recent developments worldwide in the area of natural radiation exposures and their control. For instance, the World Health Organization (WHO) released a handbook on indoor radon in 2009, and more recently the European Radon Association was formed to address the health burden due to indoor radon in Europe. It is of interest to note that the International Atomic Energy Agency (IAEA) released a revised version of the Basic Safety Standards (BSS), which includes protection of the public against indoor exposure to radon and other natural sources of radiation last May (2015) .

From such international circumstances, many articles concerning environmental radiation and radioactivity, including natural radiation exposure studies, have been published in Radiation Emergency Medicine. Therefore, the editorial board elected to change the journal name to Radiation Environment and Medicine as the continuation of Radiation Emergency Medicine from the publication of Volume 5. The scope of the journal now widely covers not only medical issues including radiation emergency medicine, but also environmental issues.

On behalf of the editorial board, we welcome your submission to the new REM.

Shinji Tokonami, Ph.D.
Editor-in-chief
Radiation Environment and Medicine

Articles

Review

An Overview of Passive-Type Detectors for Radon and Its Progeny Measurement

  • Worawat Poltabtim1, Chutima Kranrod2 and Shinji Tokonami2*

  • 1Department of Radiation Science, Graduate School of Health Sciences, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    2Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Honcho, Hirosaki, Aomori 036-8564, Japan

Abstract

Radon is well known as a radioactive gas, and the inhalation of radon and its progeny could lead to health risks, especially inducing carcinogenesis that potentially generates lung cancer. Therefore, it is essential to monitor concentrations of radon and its decay products to estimate the radiological hazards and risks to human health. In this paper, numerous studies on passive techniques for radon and its progeny have been reviewed and summarized. The mainstream of passive devices can be classified into four groups: (i) alpha track detectors, (ii) activated charcoal detectors, (iii) electret ion chambers, and (iv) thermo-luminescent dosimeters. The principle of passive devices, materials, designs, and the factors affecting their performance are discussed. This review aims to provide options and understanding of the passive techniques for radon and its progeny measurement, which have been developed for radiation protection and surveillance of radon and its progeny in various environments.

Regular Article

Thoron Equilibrium Factor Observed around Chhatrapur Placer Deposit, a High Background Radiation Area in Odisha, India

  • Yasutaka Omori1, Ganesh Prasad2, Devulapalli Vidya Sagar3, Sarata Kumar Sahoo4, Atsuyuki Sorimachi5, Miroslaw Janik4, Tetsuo Ishikawa6, Rakesh Chand Ramola2 and Shinji Tokonami1*

  • 1Hirosaki University, 66-1 Honcho, Hirosaki, Aomori 036-8564, Japan
    2H.N.B. Garhwal University, Badshahi Thaul, Tehri Garhwal 249 199, India
    3Indian Rare Earths Limited, Ganjam, Odisha 761-045, India
    4National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
    5Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585, Japan
    6Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan

     

Abstract

In thoron (220Rn)-prone areas, the contribution from thoron (including progenies) can be equal to or exceed that from radon (222Rn) during radiation exposure. The dose estimation is practically performed using the thoron concentration and thoron equilibrium factor. In the present study, thoron equilibrium factors were determined from direct measurements of thoron and its progeny concentrations for dwellings in the high background radiation area of Odisha, India. The results show that the equilibrium factor has a seasonal variation, with a minimum in winter and a maximum in summer. The frequency distributions exhibit log normality with geometric means of 0.025, 0.044, and 0.051 in winter, rainy, and summer-seasons, respectively. The annual average of 0.04 is observed to be in the order of the United Nations Scientific Committee on the Effects of Atomic Radiation recommended value (i.e., 0.02).

Report

Discussion Points of Radiation Protection for NORM Based on the IAEA Webinar “Holistic Approach to NORM Management”

  • Md. Mahamudul Hasan1* and Qinyou Zhuang1

  • 1Department of Environment Systems, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa campus, Chiba 277-8561, Japan

Abstract

International Atomic Energy Agency (IAEA) organized an online meeting on July 15, 2021, entitled ‘Holistic Approach to NORM Management Webinar,’ which shared the perspectives based on a workshop held on May 2021 in Brazil assessing the member state’s infrastructures in managing Naturally Occurring Radioactive Materials (NORM), devised valuable perspectives by providing a roadmap on the integrated system. The panelists, and/or international experts who supported the workshop summarized new NORM perspectives in the webinar. As the young participants to the webinar under the invitation of Nuclear Regulation Authority (NRA, Japan) and IAEA; the authors, in this report summarized the webinar contents on eight presentations, discussions, important/unique points (strong suggestions, new proposals, potential solutions involving IAEA critical role, countrywide strategic examples, Sustainable Development Goals (SDGs) adoption, new international standards following political feasibility, and waste handlings on NORM management) along with sharing opinions on the webinar. ‘How holistic approach is applicable in countries with inappropriate infrastructure,’ ‘harmonization,’ and ‘future decommissioning perspectives in regions which lacked disposal option’ etc. were mainly discussed in the webinar, also showed in this report based on the author’s opinion exchanges from the viewpoint of young researchers in the field of radiation protection.

Report

Utilization of Computational Fluid Dynamics Simulation for Gas Exposure Chamber

  • Kazuki Iwaoka1*, Miroslaw Janik1, Yuki Tamakuma1, 2, Masahiro Hosoda3, Shinji Tokonami3 and Reiko Kanda1

  • 1National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
    2Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
    3Hirosaki University, 66-1 Honcho, Hirosaki, Aomori 036-8564, Japan

Abstract

Testing devices and measuring physical parameters are often carried out in gas chambers. However, if the environmental conditions (e.g. gas concentration) inside the chamber is inhomogeneous, we may expect incorrect results of experiment. Confirmation of the gas distribution in various environmental conditions is an important problem in the design of the chamber. For checking the gas distribution, a theoretical approach using the computational fluid dynamics (CFD) simulation can be relatively-easily used. The article demonstrates the utilization of numerical calculations based on the CFD simulation for the analysis of gas uniformity in the virtual chamber.

Report

Meeting Report of the 8th Educational Symposium on Radiation and Health by Young Scientists (ESRAH2021) and the 4th Workshop on Radiation Research and Its Related Issue: Summary of Lectures, Presentations, and Troubleshooting When Running International Online Symposium

  • Ryo Nakayama1, 2, Yoshiaki Sato3, Kazuki Hasegawa3, Kai Takebayashi1, 2, Hikari Sato3, Eka Djatnika Nugraha3, 4, Yoshie Yachi5, Ryosuke Seino5, Tomoya Yamashita5, Hiroaki Mori5, Chutima Kranrod6, Hiroyuki Date5 and Masahiro Hosoda3, 6*

  • 1Department of Bioscience and Laboratory Medicine, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    2Department of Risk Analysis and Biodosimetry, Institute of Radiation Emergency Medicine (IREM), Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    3Department of Radiation Science, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    4Centre for Technology of Radiation Safety and Metrology (PTKMR), National Nuclear Energy Agency (BATAN) JI. Lebak Bulus Raya No. 49, Jakarta, 12440, Indonesia
    5Faculty of Health Sciences, Hokkaido University, Kita-12, Nishi-5, Kita-ku, Sapporo, Hokkaido 060-0812, Japan
    6Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan

Abstract

The 8th Educational Symposium on Radiation and Health by Young Scientists (ESRAH2021) and the 4th Workshop on Radiation Research and Its Related Issue 2021 Joint Symposium was held offsite on November 12-14, 2021. This symposium has provided an opportunity for young researchers and students to be exposed to cutting-edge research and engage in lively discussions. However, due to the restrictions of COVID-19, it has been held online for the 2nd year running. In spite of this situation, a total of about 60 participants attended and listened to lectures by established, leading researchers and poster presentations by young researchers. In this report, we summarize the lectures and oral sessions at this joint symposium, and share our troubleshooting experiences when running an online symposium.

Report

Activities of the Organization for Radiation Emergency Medicine and Cooperation Promotion in Hirosaki University

  • Ikuo Kashiwakura1*, Naofumi Akata2, Masahiro Hosoda2, 3, Tomisato Miura2, Chieko Itaki3, 4, Takakiyo Tsujiguchi1, Sadakiyo Kameya1, Katsutoshi Ito1, 5, Hiroyuki Hanada5 and Shinji Tokonami2

  • 1Organization for Radiation Emergency Medicine and Cooperation Promotion, Hirosaki University
    2Institute of Radiation Emergency Medicine, Hirosaki University
    3Graduate School of Health Sciences, Hirosaki University
    4Nursing Department – Hirosaki University Hospital
    5Advance Emergency and Critical Care Center, Hirosaki University Hospital

Abstract

Hirosaki University has been working on the development of a radiation emergency medical care system since FY 2008. Since FY 2015, it has been responsible as a national radiation emergency medical care center and has been engaged in various activities and produced human resources. Currently, with the “Organization for Radiation Emergency Medicine and Cooperation Promotion” (established in FY 2019) at its core, the university is engaged in related education and research, human resource development, regional contributions, and international collaborations. The current report presents the outline and activities of the Organization for Radiation Emergency Medicine and Cooperation Promotion at the Hirosaki University.

Report

Cytogenetic Biodosimetry in Radiation Emergency Medicine: 3. The Basics of Chromosomes for Biodosimetry

  • Akifumi Nakata1†*, Kentaro Ariyoshi2†, Yu Abe3, Yohei Fujishima4, Valerie Goh Swee Ting5, Ryo Nakayama4, 6, Kai Takebayashi4, 6, Mai Tran Thanh7, Kosuke Kasai6, Mitsuaki A. Yoshida4, 8 and Tomisato Miura4

  • 1Faculty of Pharmaceutical Sciences, Hokkaido University of Science, 15-4-1, Maeda 7-jo, Teine-ku, Sapporo, Hokkaido 006-8585, Japan
    2Center for Integrated Science and Humanities, Fukushima Medical University, 1 Hikariga-oka, Fukushima City, Fukushima 960-1295, Japan
    3Department of Radiation Biology and Protection, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan
    4Department of Risk Analysis and Biodosimetry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    5Department of Radiobiology, Singapore Nuclear Research and Safety Initiative, National University of Singapore, 1 Create Way, Singapore 138602, Singapore
    6Department of Bioscience and Laboratory Medicine, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    7Biodosimetry Group, Centre of Radiation Technology and Biotechnology, Dalat Nuclear Research Institute, 1 Nguyen Tu Luc, Ward 8, Dalat City, Lamdong Province, Vietnam
    8Institute of Chromosome Life Science, 11-5-409, Fukuokachuo 2-Chome, Fujimino-shi, Saitama 356-0031, Japan

Abstract

Chromosomes are observed during the mitotic phase of the cell-cycle. As organisms have a species-specific chromosome number and morphology, any changes in the number or morphology can be considered as chromosome aberrations. It is well known that radiation exposure causes chromosome aberrations, and multiple studies have reported on the mechanisms of radiation-induced chromosome aberrations and the effects of radiation dose and quality on chromosome aberrations. Radiation-induced chromosome aberrations can be divided into 2 categories: stable chromosome aberrations which are inherited by daughter cells in cell division (e.g. translocations, inversions, partial deletions and duplications) and unstable chromosome aberrations which cause cell death and eventually disappear (e.g. dicentrics, rings and acentric fragments). In acute external exposure, unstable chromosome aberrations are usually used as indicators for accurate dose assessment to facilitate radiation emergency medical care. On the other hand, stable aberrations are generally used for retrospective dosimetry caused by past exposures. This article summarizes the essential information on chromosomes and chromosome aberrations for cytogenetic biodosimetry.

Report

Cytogenetic Biodosimetry in Radiation Emergency Medicine: 4. Overview of Cytogenetic Biodosimetry

  • Ryo Nakayama1, 2, Yu Abe3, Valerie Goh Swee Ting4, Kai Takebayashi1, 2, Mai Tran Thanh1, 2, 5, Yohei Fujishima1, Akifumi Nakata6, Kentaro Ariyoshi7, Kosuke Kasai2, Donovan Anderson1, Hiroyuki Hanada8, Mitsuaki A. Yoshida1, 9, Katsuhiro Ito8 and Tomisato Miura1*

  • 1Department of Risk Analysis and Biodosimetry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    2Department of Bioscience and Laboratory Medicine, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan
    3Department of Radiation Biology and Protection, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, Nagasaki 852-8523, Japan
    4Department of Radiobiology, Singapore Nuclear Research and Safety Initiative, National University of Singapore, 1 Create Way, Singapore 138602, Singapore
    5Biodosimetry Group, Centre of Radiation Technology and Biotechnology, Dalat Nuclear Research Institute, 1 Nguyen Tu Luc, Ward 8, Dalat City, Lamdong Province, Vietnam
    6Faculty of Pharmaceutical Sciences, Hokkaido University of Science, 15-4-1, Maeda 7-jo, Teine-ku, Sapporo, Hokkaido 006-8585, Japan
    7Center for Integrated Science and Humanities, Fukushima Medical University, 1 Hikariga-oka, Fukushima City, Fukushima 960-1295, Japan
    8Advanced Emergency and Critical Care Center, Hirosaki University Hospital, Hirosaki University, 53 Hon-cho, Hirosaki, Aomori 036-8563, Japan
    9Institute of Chromosome Life Science, 11-5-409, Fukuokachuo 2-Chome, Fujimino-shi, Saitama 356-0031, Japan

Abstract

Dose estimation is performed to provide physicians individual doses of patients exposed to radiation for medical treatment in radiation emergency medicine. Cytogenetic dose assessment plays an important role in radiation medicine because it directly analyzes the in vivo response of exposed patients and accurately estimates acute whole-body exposure. The endpoint used as a biological dosimeter in cytogenetic dose assessment fulfils three requirements: (1) specificity, (2) stability, and (3) dose-dependency. Dicentric chromosome (Dic) assay (DCA) is recognized as the gold standard in biodosimetry because Dic is an excellent endpoint that meets all three requirements of a biological dosimeter. In addition to DCA, premature chromosome condensation assay, cytokinesis block micronucleus assay, and translocation assay are used in cytogenetic dose assessment. As the endpoints of each assay are different, the most suitable method is selected according to the exposure scenario in terms of partial/whole-body exposure and applicable dose range. This article outlines the characteristics of cytogenetic dose assessment methods, reagents used for blood culture, and precautions for harvesting and spreading in chromosome preparation.