Methods of Evaluating the Radioactive Effects of the Fukushima Nuclear Accidents

  • DATE / TIME:
    2013•12•20    14:00 - 17:00

    On 20 December 2013, the Fukushima Global Communication programme convened an international seminar on “Methods of Evaluating the Radioactive Effects of the Fukushima Nuclear Accidents” at the United Nations University in Tokyo, Japan. The seminar featured a keynote speech by Dr. Jacques Repussard and was attended by representatives of research institutes, governmental bodies, embassies, and the media. The programme of events and a report on the proceedings are available below.

    Symposium Programme:

    14:00 Opening Session:

    • Opening Remarks by Professor Kazuhiko Takeuchi (Senior Vice-Rector, United Nations University)

    14:10 Keynote Speech

    • Dr. Jacques Repussard, Director General, IRSN – “Forecasting, estimating, evaluating and communicating the environmental and public health effects of a major nuclear accident: How can Fukushima contribute to the development of international best practice?” [pdf / video]

    14:45 Break

    15:00 Panel Discussion

    [Moderator] Mr. Hideyuki Mori (President, Institute for Global Environmental Strategies)


    • Dr. Mikazu Yui (Deputy Director of Fukushima Environmental Safety Center, Japan Atomic Energy Agency) [pdf]
    • Dr. Kimio Tanaka (Ex-Director of Department of Radiology, Advisor, Institute for Environmental Sciences) [pdf]
    • Mr. Christophe Xerri (Embassy of France in Japan) [pdf]
    • Dr. Atsuro Tsutsumi (Research Fellow, UNU International Institute for Global Health) [pdf]

    16:45 Wrap-up and Closing

    • Prof. Kazuhiko Takeuchi (Senior Vice-Rector, United Nations University)

    17:00 Closing

    Symposium Report:

    (Prepared by Dr. Ana Mosneaga and Ms. Alexandra Ivanovic)

    On 20 December 2013, the Fukushima Global Communication Programme of the United Nations University Institute for Sustainability and Peace in Tokyo, hosted an international seminar titled “Methods of Evaluating the Radioactive Effects of the Fukushima Nuclear Accidents.” The seminar discussed a broad range of topics including, how an evaluation of the Fukushima nuclear accident could contribute to international best practice, current remedial actions for decontamination, results of experiments on low level radiation dosage and an evaluation of the impact of nuclear disasters on the mental health well-being of affected communities.

    The key note speaker, Dr Jacques Repussard (Director General of the Institute for Radiological Protection and Nuclear Safety (IRSN) in France) had visited Fukushima prior to the seminar with a team of analysts and journalists from France.  Comparing the French and Japanese systems of nuclear safety, Dr Repussard stressed in particular, the independence of the IRSN which provides the French government with scientific knowledge and investigates all range of nuclear issues independently of the government and nuclear plant operators.  He emphasised the importance of the public’s role as an actor in French nuclear safety issues. These local committees were a “vector” of nuclear safety, able to receive answers on their questions regarding nuclear safety and make suggestions.  He emphasised that both the public and government must trust the institution that gives information and advice in relation to nuclear safety and that as such trust needs to be generated through long term collaboration.

    With regard to how the French deal with emergency preparedness for potential nuclear disasters, Dr Repussard underlined: anticipation (i.e. predicting consequences of a disaster on society and industry as well as impacts of unforeseen weather events), operational interconnection (where safety and radiation protection was merged and this requires good communication between the nuclear operators and experts) and transparency (where the IRSN must be willing to show its expertise and the results of its actions with public communication and access to this information being the most important).

    Finally, Dr Repussard discussed the lessons learned from Fukushima, noting firstly that the costs of the nuclear accident were underestimated.  He also noted the complexity of keeping the international community informed of the situation while at the same time dealing with the disaster in real time and recommended planning for how such communication would be disseminated. The third lesson Dr Repussard observed from Fukushima concerned the management of a radiological risk.  He felt it was a mistake to manage exposure by using Becquerels as a measurement. Instead he was of the opinion that the real dose to people needed to be known otherwise unnecessary evacuation could cause other societal impacts such as increases in divorce and stigmatisation of self evacuees compared to forced evacuees. He felt not enough had been done in Japan to communicate the risk and this should be explained from the local level up to the national government.  Overall, he observed that the Fukushima disaster also showed that the Japanese government was not sufficiently prepared to deal with the crisis effectively.  He said communication with the public was important, and discussions should be held with mayors at a local level as to how to keep communities together and to gain the trust of the people.

    In conclusion Dr Repussard emphasised the importance of sharing lessons internationally and importantly, that local stakeholders should be taken on board in the decision making process and provide information to the public.

    Dr Mikazu Yui, (Deputy Director, Fukushima Environmental Safety Centre, Japan Atomic Energy Agency (JAEA)), discussed the JAEAs current remedial activities in Fukushima focussing on the decontamination of Cesium-137 which has a half life of 30 years. He gave an example of a pilot project to decontaminate farmland with the removal of the top layer of soil but then pointed out the problem of disposing of the huge amount of soil waste and opposition by locals to building storage facilities for such waste.  Decontaminating forest areas (covering nearly 70% of Fukushima’s territory) was noted to be especially difficult with particular concern being how cesium is transported from forests to rivers and then the ocean.  JAEA has initiated the Fukushima-TRACE project to do a long term assessment of the transportation of this contaminant, which looks at the depths of profile of cesium in forest topsoil and measures the dose rate distribution in rivers.

    Dr Kimio Tanaka, (Former Director, Department of Radiobiology and Adviser, Institute for Environmental Sciences), presented results of the experiments carried out on mice exposed to low levels of radiation over a certain period. The experiment concluded that mice exposed to a total of 400 milligrays over a 400 day period induced life shortening in the mice whereas exposure at 20 milligrays over the period had no life shortening effect.  A second part of the experiment which measured the effect on chromosome aberration with increased dosage of radiation concluded that such aberrations increased with dosage.  It also found that as dose rates of irradiation were reduced to between 1 milligray per day and 20 milligrays per day, biological effects also reduced with most DNA damage being repaired and the aberration rate reducing over time.  Such results would be useful for estimating the risk of low dose rate radiation exposure and radiation protection in health management studies for Fukushima victims.

    Mr Christophe Xerri, (Nuclear Counsellor, Embassy of France in Japan), discussed the importance of public trust in nuclear safety institutions and the need for such institutions to be independent and transparent. He highlighted the importance of looking at the human factors of the disaster and discussed in some detail the Local Information Committees in France which had a consultative role in discussing issues of concern between the public and nuclear plant operators. Such committees are comprised of various stakeholders including NGOs and would often raise questions not taken into account by technical experts.

    The final panellist, Dr Asturo Tsutumi, (Research Fellow,  UNU International Institute for Global Health), emphasised that mental well-being was a key to human security and discussed how mental health figures worsened in disaster settings.  He stated that 2688 people died of disaster related deaths in Tohoku. Noting that research in the aftermath of the Great Hanshin Earthquake showed that mental health issues became more prevalent 3 years after the event, Dr Tsutumi underlined the  importance of addressing the mental health issues of Fukushima evacuees now.  He recommended the integration of mental health well-being into recovery and development efforts as a key indicator.

    After panel presentations, questions were first raised by the seminar moderator, Mr Hideyuki Mori (President, Institute for Global Environmental Strategies).  Mr Mori asked Dr Tanaka about how the results of the experiment could be applied to Fukushima.  Dr Tanaka responded that perhaps the current levels could be relaxed to allow people to return where exposure was less than 5 milligrays per year but that such decisions should be addressed individually and at the family unit level.

    In response to a question about the importance of communicating information to the public, Dr Tsutumi discussed the cultural tendency in Japan to hide symptoms of mental depression and the need to design effective mechanisms to help the affected people to improve their mental well-being.

    A number of questions from the audience were regarding the lack of agreement between experts on radiation dosage, highlighting that the current rate of 1 millisievert per year were scientifically and internationally unsupported.  Mr Xerri pointed out that the Japanese government was not prepared for the disaster and did not provide accurate information from a scientific point of view. In France, guidelines were established after Chernobyl on how to react to such questions from the public, emphasising that general information should be provided with less emphasis on specific figures.  It was now important to give the correct information to people and about how dosage is received, even to the extent of people having their own dosimeter where they can monitor radiation levels themselves and with such information can make informed decisions about whether they are willing to return or not.

    A final question from Mr Christopher Hobson (Visiting Fellow, UNU), was about how to re-establish public trust in the government which had been lost in the aftermath of the disaster.  Mr Xerri responded that some villagers had sought their own trustful sources of information through establishing contacts with respected experts such as university professors that enabled them to get relevant advice without having to wait for the official information from the government.  Dr Tsutumi added an observation that information from the local community stakeholders, e.g. nurses and municipal officials, was considered most reliable by the local population and that perhaps the government and international organisations could consider mediating information through to these stakeholders to ensure that it is disseminated in a format that is easy to relate to for the local people.

    The final concluding comments by Professor Kazuhiko Takeuchi, (Senior Vice-Rector, UNU), summarised the afternoon’s discussion:

    • Correct information needs to be disseminated and understood and more respect needs to be given to local information
    • Discussions must be transparent and all stakeholders views must be heard
    • To restore lost trust from Fukushima means more hard work is required to have good communication with local residents
    • The radiation dose needs to be discussed from an international, scientific and local perspective and revisited so that restoration can be comprehensively considered.