Annals of the ICRP最新文献

This paper does not necessarily reflect the views of the International Commission on Radiological Protection.Ten years have passed since the accident at Fukushima Daiichi nuclear power plant, and radioactive substances contained in agricultural products and marine products are now below detectable levels. Amidst this, the testing stance is changing from one that guarantees safety to one that guarantees relief, and testing is being reduced for financial reasons. Moreover, the sense of resistance and concern towards food products produced in Fukushima Prefecture is reducing. Anxiety has been reducing along with the development of the inspection system, the inspection results, and the passage of time. However, although there have been fewer requests, demands, and claims to avoid products from Fukushima Prefecture since immediately after the accident, there is a tendency for consumer trends to be forcefully 'surmised'. As a result, the problem of reputational damage, such as the fact that the market ranking of rice and beef has not recovered, remains an issue.

At the ICRP International Conference on Recovery After Nuclear Accidents Session 3.4 Forum on the Transmission of Experience held in December 2020, a panel discussion took place on the topic, 'How to overcome the difficulty to talk about the experience of nuclear accidents?'. The facilitator was Ryoko Ando (NPO Fukushima Dialogue) and the following six people participated as panelists: Atsushi Chiba (teacher at Fukushima Prefectural Asaka High School), Yoshiko Aoki (NPO Group of Storytellers About 311 in Tomioka), Miku Endo (Great East Japan Earthquake and Nuclear Disaster Memorial Museum), Kenji Shiga (former Director of Hiroshima Peace Memorial Museum), Thierry Schneider (Centre d'étude sur l'Evaluation de la Protection dans le domaine Nucléaire), and Noboru Takamura (Director of Great East Japan Earthquake and Nuclear Disaster Memorial Museum, Nagasaki University).

In 2020, the International Commission on Radiological Protection (ICRP) issued Publication 146 which provides a framework of the radiological protection of people and the environment in the case of a large nuclear accident. Mitigation of radiological consequences is achieved using the fundamental principles of justification of decisions and optimisation of protection. These recommendations emphasise the importance of the optimisation of protection for the rehabilitation of living and working conditions in the affected areas during the intermediate and long-term phases. They underline the role of co-operation between the authorities, experts, and the affected population in the co-expertise process to facilitate informed decisions about their own protection. ICRP defines reference levels to be selected within generic bands of exposure considering the induced risk of radiation, as well as the feasibility of controlling the situation.

This paper does not necessarily reflect the views of the International Commission on Radiological Protection.Beyond the consideration of radiological aspects, the rehabilitation of living and working conditions after a large nuclear accident is a complex process in which all dimensions of individual and community life are involved and interconnected. Responsibles of socio-economic entities are facing various difficulties/challenges, including the implementation of protective actions for ensuring the protection of employees, the continuity of production of good-quality products in affected areas, and restoring the confidence of consumers. For affected local communities, the deployment of a socio-economic programme is essential to enable a sustainable future while recognising that a return to the pre-accident situation is generally not achievable. In this context, supporting the societal and economic dynamics of the recovery process requires the adoption of specific governance mechanisms respecting a series of ethical and social values, as highlighted by lessons from the post-accident management of the Chernobyl and Fukshima accidents at Chernobyl and Fukushima Daiichi nuclear power plants.

Following the accident at Fukushima Daiichi nuclear power plant, Fukushima Prefecture is conducting the Fukushima Health Management Survey, which has been contracted out to Fukushima Medical University. The purpose of this survey is to investigate the exposure doses and health conditions of the residents of Fukushima Prefecture in order to prevent, diagnose, and treat diseases at an early stage, and to maintain and improve the health of residents in the future.This survey consists of a basic survey to estimate external exposure doses and detailed surveys to investigate health conditions. The detailed surveys comprise: (i) thyroid ultrasound examination; (ii) comprehensive health check; (iii) mental health and lifestyle survey; and (iv) pregnancy and birth survey.In the basic survey, the external exposure dose was estimated for >466,000 people during the first 4 months after the accident; it was estimated to be <5 mSv for 99.8% of residents.The thyroid ultrasound examination included four rounds of echo examinations covering approximately 380,000 children aged <18 years at the time of the accident in each round. The first, second, third, and fourth examinations identified 116, 71, 31, and 21 children with thyroid cancer/suspected cancer, respectively. The Fukushima Prefectural Oversight Committee analysed the results from the first and second examinations, and evaluated that 'the detected increased rate is unlikely to be the impact of radiation'. However, the Oversight Committee is deliberating the future direction of thyroid examination, taking into consideration the advantages and disadvantages of the examination as well as ethical viewpoints.In the comprehensive health check, approximately 210,000 people in the evacuation area were examined, and increased rates of lifestyle-related diseases [e.g. obesity, hypertension, diabetes, and dyslipidaemia (low high-density-lipoprotein cholesterol)] were confirmed. In the mental health and lifestyle survey, approximately 210,000 people, including residents in the evacuation area, were examined. A deterioration in general mental health was found for the period immediately after the accident across a wide range of age groups, and although recovery was seen over the years, the rate of mental health issues remains above the national average. The pregnancy and birth survey revealed that the pre-term birth rate, low-birthweight rate, and rate of congenital anomalies did not differ from the national average.The purpose of Fukushima Health Management Survey is not only to collect data on the health of the residents of Fukushima Prefecture, but to provide direct support to residents regarding the health issues clarified by the survey. Moreover, various initiatives are being implemented in cooperation with various local government authorities with the aim of maintaining and promoting the health of the residents.

Estimates of thyroid doses to the public from radioiodine intake following the accidents at Chernobyl and Fukushima Daiichi nuclear power plants are compared. The basis for thyroid dose estimates after the Chernobyl accident was a large set of measurements of ¹³¹I thyroidal content for approximately 400,000 residents in Belarus, Ukraine, and Russia. Due to a lack of direct thyroid measurements after the Fukushima accident (just over 1000 residents were measured), thyroid doses were estimated based on ecological models and are therefore associated with much higher uncertainty than those based on direct thyroid measurements. Thyroid dose estimates for evacuees were up to 50,000 mGy for Chernobyl and up to approximately 100 mGy for Fukushima. This large difference in thyroid dose to the public is mainly due to the different dominant pathways of radioiodine intake: ingestion of fresh, locally produced cows' milk (Chernobyl) and inhalation of contaminated air (Fukushima).