Pre-disaster family visits and post-evacuation return to Fukushima among psychiatric inpatients evacuated to out-of-area hospitals after the nuclear accident.

OBJECTIVE: This study aimed to elucidate the effects of pre-evacuation family hospital visits on post-evacuation returns to Fukushima Prefecture (hometown) among psychiatric inpatients who mandatorily evacuated to hospitals outside the prefecture because of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. METHOD: Of the inpatients in Fukushima, 44 were admitted to a hospital in the nearby Soso district on March 11, 2011, and were therefore included in the current analysis. We collected information on their discharge after the evacuation and family visits before the evacuation by reviewing the medical records of both the evacuation destination and former hospitals. RESULTS: The average durations from the accident to post-evacuation return among patients with and those without former family visits were 681.8 days (standard error [SE] = 163.3) and 1,027.8 days (SE = 152.0), respectively. The log-rank test showed a tendency of earlier return to Fukushima among inpatients who had received family visits to the hospital before evacuation (p = .073). CONCLUSIONS: The results highlight the critical need for close collaboration between psychiatric medical practitioners and families, to not only support patients' community reintegration into daily life but also facilitate a timely return to their hometowns following long-distance evacuation caused by an unforeseen large-scale disaster.

Characteristics of exposure to radioactive iodine during a nuclear incident.

BACKGROUND: During a nuclear accident, numerous products of nuclear fission are released, including isotopes of radioactive iodine. Among them is iodine-131, with a half-life of 8.02 days, which emits ß radiation. For decades, it has been effectively and safely used in medicine. However, in the event of a nuclear accident, uncontrolled exposure can have harmful biological effects. The main sources of internal contamination with iodine-131 are contaminated air, food and water. The most exposed organ is the thyroid gland, where radioactive iodine accumulates via the Na+/I- symporter (NIS). NIS does not distinguish between radioactive iodine isotopes and the stable isotope iodine-127, which is essential for the synthesis of thyroid hormones. Exposure to radioactive iodine during a nuclear accident is primarily associated with papillary thyroid cancer, whose incidence begins to increase a few years after exposure. Children and adolescents are at the highest risk, and the risk is particularly significant for individuals living in iodine-deficient areas. CONCLUSIONS: Ensuring an adequate iodine supply is therefore crucial for lowering the risk of the harmful effects of exposure to radioactive iodine at the population level. Protecting the thyroid with potassium iodide tablets significantly reduces radiation exposure, as stable iodine prevents the entry of radioactive iodine into the thyroid. Such protection is effective only within a narrow time window - a few hours before and after the exposure and is recommended only for those under 40 years of age, as the risks of excessive iodine intake outweigh the potential benefits in older individuals.

Adaptation of FDMT to include process-based models and consider regional aspects following radionuclide deposition events.

Experience from earlier nuclear accidents has clearly shown the need for maintaining and developing appropriate modelling capabilities. Dealing with complex issues such as human exposure following a nuclear accident necessitates the implementation of a set of interconnected models such as FDMT. FDMT is an integrated module within the two main European decision support systems for radiological emergency preparedness, ARGOS and JRODOS, to simulate the transfer of radionuclides along terrestrial food chains and to predict their activity concentrations in foodstuffs. In order to make the module more fit-for-purpose, FDMT has been implemented in a new modelling platform (ECOLEGO) which provides a high degree of flexibility with regard to conducting developmental work. This paper presents improvements in FDMT further through either the incorporation of new models or further elaboration of existing ones, as well as updates in default parameters. Models have also been made more fit-for-purpose through consideration of regional-specific parameters. Specific improvements include modelling developments related to dry deposition, radioactive particle weathering, radiocaesium transfer influenced by soil characteristics and, for a region-specific case, animal uptake. In addition, the paper presents new pathways and parameters (and updated values) to be considered for making FDMT more adapted for Norwegian conditions. Overall, the improvements made in the present work should significantly reduce the uncertainties associated with the outputs of the FDMT models.

A detailed simulation study on radionuclide dispersion under spent fuel road transportation conditions: Effects of vessel type and coniferous vegetation growth.

Vegetation barriers are an important environmental characteristic of spent fuel road transportation accidents. Spent fuel vessels may be affected by force majeure factors during transportation, which leads to damage to spent fuel assemblies and containers and can cause radionuclides to gradually release from assemblies to vessels to the external environment. In this work, considering the growth periods of coniferous vegetation barriers and vessel type, a radionuclide dispersion model based on computational fluid dynamics (CFD) was established by adding a decay term and a pressure loss term. The simulations showed that, first, compared to the small (Type-II) vessel, the effects of fluid flow around the large vessel (Type-I) have a more significant impact on radionuclide dispersion. The backflow around the Type-I vessel causes leaked radionuclides to disperse towards the vessel, and the larger the vessel is, the more significant the rise of the leaked radionuclide plume tail will be due to the increased negative pressure gradient area. Moreover, the area contaminated exceeding the maximum allowable concentration by radioactivity for the Type-I vessel is reduced gradually with the growth of coniferous vegetation barriers due to the weakening of the backflow effect by growing vegetation. Second, compared to vegetation barriers of 15 years and 23 years, the horizontal distance exceeding the maximum allowable concentration of the leaked 131I dispersion from Type II vessels near vegetation barriers for 12 years is the longest. The older the vegetation barrier is, the shorter the horizontal dispersion range, and the shape of radionuclide dispersion gradually transforms from flat to semicircular with vegetation barrier growth, but this could cause a greater radioactive accumulation effect near the leakage point, and the maximum concentration of leaked 131I reached 0.54 kBq·m-3 for leaked radionuclides from the Type II vessel under vegetation barriers of 23 years. In addition, improvement suggestions based on the proposed method are presented, which will enable the Standards Institutes to apply the research methodologies described herein across various scenarios. ENVIRONMENTAL IMPLICATION: Compared to nonradioative pollutants, radioactive pollutants are intercepted by vegetation barriers and then migrate to the soil through leaves, stems, and roots, which can contaminate the surrounding environment. Considering the effects of vessel type and coniferous vegetation growth, a radionuclide dispersion model based on CFD was established. Suggestions for decontaminating radioactive pollution areas have been proposed based on the simulation results of hypothetical scenarios. The scenario applicability improvements based on the proposed model could assist relevant Standards Institutes to making improving measures.

Field Test of the MiniRadMeter Gamma and Neutron Detector for the EU Project CLEANDEM.

In the framework of the H2020 CLEANDEM project, a small robotic vehicle was equipped with a series of different sensors that were developed for the preliminary inspection of areas possibly contaminated by radiation. Such unmanned inspection allows to identify dangerous locations prior to the possible start of human operations. One of the developed devices, named the MiniRadMeter, is a compact low-cost sensor that performs gamma and neutron radiation field mapping in the environment. The MiniRadMeter was successfully tested in a simulated field mission with four "hidden" radioactive sources and a neutron generator. In this work, we describe the test procedure and the results, which were supported by the outcome of dedicated Monte Carlo simulations.

Impact of the Great East Japan Earthquake followed by the nuclear power plant accident on the nursing students' academic progress in Soma, Fukushima, Japan: a retrospective cohort study with questionnaire survey.

BACKGROUND: The Great East Japan Earthquake and the subsequent Fukushima nuclear power plant accident in 2011 posed significant challenges to the educational sector, particularly affecting nursing students in the disaster area. However, to the best of our knowledge, there are no reports on the effects of the natural disaster coupled with the nuclear accident on the nursing students. Therefore, this study aimed to determine the impact of the Fukushima disasters on rate of academic failure events in nursing education. METHODS: A retrospective cohort approach was conducted, focusing on 677 students from Soma Nursing School admitted between 2001 and 2017. Four failure events-failure to pass the national examination, student retention, suspension, and withdrawal from school-were compared between three time periods: pre-disaster, early peri-disaster, and later peri-disaster. This analysis was followed by a questionnaire survey among the students and an interview with faculty members to gain further insights. RESULTS: Of the student cohort, 17% had at least one failure event. Students in the later peri-disaster phase faced an elevated failure rate at 29%. Variables such as being male, admission during later peri-disaster period, and local pre-admission residence played a significant role in these failure events in multivariate logistic regression analysis (adjusted odds ratio [95% confidence interval, p value]; 2.63 [1.49-4.64, < 0.001], 3.207 [2.00-5.15, < 0.001], and 1.84 [1.12-3.02, 0.02], respectively). CONCLUSIONS: This study highlights the impact of the Great East Japan Earthquake and the following nuclear accident on nursing education. The elevated failure rates in the later peri-disaster period emphasize the challenges posed by continuing disaster phases. Thus, there is a need for intensified and tailored strategies in nursing education in disaster-affected regions.

Case Report: Difficulties faced by a home oxygen therapy patient who died after the Fukushima Daiichi nuclear power plant accident.

Following the Great East Japan Earthquake (GEJE) and the Fukushima Daiichi nuclear power plant accident in 2011, mandatory evacuation orders were issued to residents living near the nuclear power plant in Fukushima prefecture, including some patients receiving home oxygen therapy. Although the vulnerability of patients with home oxygen therapy (one of the population groups most vulnerable to disasters) has been noted, there is little information on the health effects of evacuation in the event of a radiation disaster. A 90-year-old man diagnosed with chronic obstructive pulmonary disease since the age of 70, and lived in a town located approximately 20 km south of the nuclear power plant, died 8 months after the disaster due to worsening health conditions. This case reveals the potential for both physical and psychological burdens experienced by vulnerable groups like patients undergoing home oxygen therapy during evacuations in times of disaster. Although it is only a case report and the information is limited, severe respiratory distress requiring home oxygen therapy may present a significant risk factor for disaster-related deaths, especially in cases where evacuations are prolonged, such as in nuclear disasters. Due to the challenge of obtaining prompt public support immediately after a disaster, home oxygen therapy patients may need to prioritize self-help and mutual assistance in their disaster preparedness efforts.

Long-term evacuation and obesity: a 12-year follow-up comparative study of residents inside and outside Katsurao Village after the Fukushima nuclear disaster.

Objective: Evacuation, owing to a disaster, impacts various aspects of an individual's life, including health status. This study aimed to determine the prevalence of obesity among residents of Katsurao Village, Fukushima Prefecture, after the evacuation order due to the Fukushima nuclear disaster in 2011 was lifted in 2016 and to compare the prevalence of obesity by place of residence (inside or outside the village). Methods: The number of examinees, sex, age, place of residence, body mass index (BMI), exercise habits, smoking habits, drinking habits, and dietary status were extracted from the results of health checkups since 2016. We compared the BMI of the indigenes of Katsurao Village by place of residence (inside or outside the village) over time. Results: Although 7 years have passed since 2016, ~70% of the registered residents of Katsurao Village still live outside the village. The obesity rates have consistently been higher among people living outside the village compared to those inside, and the place of residence was the only factor significantly associated with obesity. Conclusion: The findings of this study suggest early intervention is necessary to prevent health risks associated with disaster evacuation if the evacuation period is prolonged.

Update on radiation protection of the thyroid gland.

In recent years, concern about the effects of ionizing radiation on exposed individuals has led to the need to regulate and quantify the use of diagnostic and therapeutic techniques. Geopolitical events in recent times have also increased the population's perception of insecurity regarding ionizing radiation, and we increasingly face patients reluctant to undergo certain types of scans in our nuclear medicine services and, albeit less frequently, in radiology services. This article aims to summarise the extent to which ionizing radiation is present in our daily lives and how diagnostic and therapeutic procedures can affect our health, particularly from the perspective of their effects on the thyroid gland, one of the body's most radiation-sensitive organs.

Basic Performance Evaluation of a Radiation Survey Meter That Uses a Plastic-Scintillation Sensor.

After the Fukushima nuclear power plant accident in 2011, many types of survey meters were used, including Geiger-Müller (GM) survey meters, which have long been used to measure ß-rays. Recently, however, a novel radiation survey meter that uses a plastic-scintillation sensor has been developed. Although manufacturers' catalog data are available for these survey meters, there have been no user reports on performance. In addition, the performance of commercial plastic-scintillation survey meters has not been evaluated. In this study, we experimentally compared the performance of a plastic-scintillation survey meter with that of a GM survey meter. The results show that the two instruments performed very similarly in most respects. The GM survey meter exhibited count losses when the radiation count rate was high, whereas the plastic-scintillation survey meter remained accurate under such circumstances, with almost no count loss at high radiation rates. For measurements at background rates (i.e., low counting rates), the counting rates of the plastic-scintillation and GM survey meters were similar. Therefore, an advantage of plastic-scintillation survey meters is that they are less affected by count loss than GM survey meters. We conclude that the plastic-scintillation survey meter is a useful ß-ray measuring/monitoring instrument.

Records of the riverine discharge of 129I in riverbank sediment after the Fukushima accident.

Although 129I discharge from watersheds is fundamental for assessing long-term radiation effects on aquatic ecosystems, 129I originating from the Fukushima nuclear accident is yet be evaluated. This study investigated the transport behavior of 129I by riverbank surveys conducted from 2013 to 2015 in a watershed where the 129I/137Cs activity ratio is low in the mountainous area and high in the plain as of 2011. Until 2015, the 129I/137Cs activity ratio of the levee crown in the studied watershed was similar to that of the surrounding area in 2011. However, the 129I/137Cs ratios of the surface riverbank sediments were all low, indicating that radionuclides transported from the mountainous area were deposited on the riverbank in the plain. The vertical distribution of the 129I/137Cs ratio in the riverbank sediments indicated that some 129I and 137Cs deposited during the accident remained in the lower layers, but most were eroded immediately after the accident. Based on the 129I/137Cs ratios of sediments deposited on the riverbank, which remained constant until 2015 after the accident, the amount of 129I discharged to the ocean was determined from the previously evaluated 137Cs discharge. It was calculated that 1.8 × 105 Bq and 1.2 × 107 Bq of 129I were discharged with sediment from the studied watershed and the contaminated river watersheds (Abukuma River and Fukushima coastal rivers, including the study river), respectively. This amount of 129I was 0.3% of the 129I released from the Fukushima Dai-ichi Nuclear Power Plant into the ocean immediately after the accident. Furthermore, a comparison of the 129I/137Cs ratio showed that the continuous 129I and 137Cs discharge from the river contribute little to their amount in the seafloor sediments along the Fukushima coast.

Association between evacuation and becoming overweight after the Great East Japan Earthquake: a 7-year follow-up of the Fukushima Health Management Survey.

OBJECTIVES: Disaster evacuation increases the risk of becoming overweight or obese owing to lifestyle changes and psychosocial factors. This study evaluated the effect of evacuation on becoming overweight during a 7-year follow-up among residents of Fukushima Prefecture during the Great East Japan Earthquake. STUDY DESIGN: This was a prospective cohort study. METHODS: We analysed data collected from 18,977 non-overweight Japanese participants who completed the 'Comprehensive Health Checkup Program' and 'Mental Health and Lifestyle Survey', as part of the Fukushima Health Management Survey, between July 2011 and November 2012. An evacuation was defined as the moving out of residents of municipalities designated as an evacuation zone by the government or having a self-reported experience of moving into shelters or temporary housing. Follow-up examinations were conducted in March 2018 to identify patients who became overweight. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using a Cox proportional hazards regression model. RESULTS: Among 15,875 participants (6091 men and 9784 women; mean age 63.0 ± 11.1 years) who received follow-up examination (mean follow-up, 4.29 years), 2042 (856 men and 1186 women) became overweight. Age-, baseline body mass index-, lifestyle-, and psychosocial status-adjusted HRs (95% CIs) for becoming overweight after evacuation were 1.44 (1.24-1.66) for men and 1.66 (1.47-1.89) for women. CONCLUSION: Evacuation was associated with the risk of becoming overweight 7 years after the disaster. Thus, maintaining physical activity, healthy diet, and sleep quality and removing barriers to healthy behaviour caused by disasters, including anxiety concerning radiation, may prevent this health risk among evacuees.

Source term inversion of short-lived nuclides in complex nuclear accidents based on machine learning using off-site gamma dose rate.

During nuclear accidents, large amounts of short-lived radionuclides are released into the environment, causing acute health hazards to local populations. Therefore, it is particularly important to obtain source-term information to assist nuclear emergency decision makers in determining emergency protective measures. However, it is extremely difficult to obtain reliable contaminant monitoring instrument readings to estimate the source term based on core conditions, release routes, and release conditions. Currently, a wide variety of source-term inversion methods are attracting increasing attention. In this study, the release rates of four typical short-lived nuclides (Kr-88, Sr-91, Te-132, I-131) in two complex nuclear accident scenarios were estimated using a machine-learning method. The results show that the best estimation performance is obtained with the long short-term memory network, and the mean absolute percentage errors for the release rates of the four nuclides at 10 h under the two nuclear accidents are 9.87% and 11.08%, 17.49% and 16.51%, 7.16% and 8.35%, and 38.83% and 41.87%, respectively. Meanwhile, the mean absolute percentage errors for Te-132 (7.16% and 8.35%) were the lowest among all the estimated nuclides. In addition, stability analysis showed that the gamma dose rate was the key parameter affecting the estimation accuracy.

Radiation Dose Does Not Affect the Predictive Value of Thyroid Biopsy for Diagnosing Papillary Thyroid Cancer in a Belarusian Cohort Exposed to Chernobyl Fallout.

INTRODUCTION: The Chernobyl nuclear accident exposed residents of contaminated territories to substantial quantities of radioiodines and was followed by an increase in thyroid cancer, primarily papillary thyroid cancer (PTC), among exposed children and adolescents. Although thyroid biopsy is an essential component of screening programs following accidental exposure to radioiodines, it is unknown whether the predictive value of biopsy is affected by different levels of environmental exposure. METHODS: A cohort of 11,732 Belarusians aged ≤18 years at the time of the Chernobyl accident with individual thyroid radiation dose estimates was screened at least once 11-22 years later. Paired cytologic conclusions and histopathologic diagnoses were possible for 258 thyroid nodules from 238 cohort members. Cytologic conclusions were divided into five reporting categories, with all follicular lesion aspirates combined into a single indeterminate category. Standard performance indicators, risk of malignancy (ROM), and odds ratios for a correct cytologic conclusion were calculated, both overall and according to quintile of thyroid radiation dose. RESULTS: The arithmetic mean thyroid dose estimate for the study group was 1.73 Gy (range: 0.00-23.64 Gy). The final histopathologic diagnosis was cancer for 136 of 258 biopsies (52.7%; 135 papillary and 1 follicular). The overall ROM was 96.7% for cytologies definite for PTC, 83.7% for suspicious for PTC, 33.0% for indeterminate, 8.1% for benign, and 31.0% for non-diagnostic. The ROM showed little change according to level of radiation exposure. Overall, there was no association between thyroid radiation dose and the odds ratio for a correct cytologic conclusion (p = 0.24). When analyzed according to dose quintile, the odds ratio for a correct conclusion increased two-fold at 0.10-0.29 Gy compared to a dose of 0.00-0.09 Gy and decreased at doses of 0.3-24 Gy (p value for linear trend = 0.99). CONCLUSIONS: At radiation doses received by a cohort of young Belarusians exposed to radioiodines by the Chernobyl accident, the predictive value of thyroid biopsy for diagnosing PTC was not significantly affected by level of radiation exposure.

Factors affecting the changes in body mass index among emergency workers at the Fukushima Daiichi Nuclear Power Plant.

Understanding the effects of lifestyle and radiation on health is important for the health management of disaster recovery workers. International research has demonstrated the relationship between natural disasters and diseases. The lifestyle and working conditions following the Great East Japan Earthquake potentially increased the incidence of cardiovascular disease and obesity among affected individuals. The aim of this study was to analyze the body mass index (BMI) of 1,341 emergency workers who responded to the accident at the Fukushima Daiichi Nuclear Power Plant. The BMI of each emergency worker was measured immediately after the accident and compared with that measured at the initial survey conducted 5 yr later to determine the effect of lifestyle habits on BMI. Awareness of the frequency of eating out and caloric intake helped maintain their BMI, while evacuation contributed to the increase in BMI. Prevention of obesity, which can trigger or exacerbate certain health conditions, such as heat exhaustion, infection, and cerebro-cardiovascular disease, requires diet counseling, with a focus on maintaining adequate caloric intake; moreover, special consideration should be provided to evacuated workers.

The "GU-GU-RU" project to eliminate discrimination related to the health effects of the Fukushima nuclear accident.

BACKGROUND: Although 12 years have passed since Great East Japan Earthquake and following Fukushima nuclear accident, approximately 40% of Japanese citizen still believe that the current radiation exposure in Fukushima residents will likely/ very likely to cause genetic effects of radiation. This incorrect understanding could continue unexpected discrimination and prejudice towards those from Fukushima now and in the future. In order to provide updated knowledge and eliminate rumors related to radiation, Japanese Ministry of the Environment has launched "GU-GU-RU" project in 2021 with consisting of five sections. OBJECTIVE: (1) To discuss the objectives and effects of the "GU-GU-RU" project (results after the first year), (2) to present administrative measures that may be effective in the long-term to prevent unjustified discrimination and prejudice, and (3) to eliminate rumors in the event of future large-scale disasters, including radiation disasters. METHODS: We showed the contents of each sections carried out under the project and observed the result of first-year activities in each section. RESULTS: Among the programs, the "Radiation College" has steadily produced positive results, with nearly 1,300 students participating and 50 students sharing their thoughts and ideas. In addition, the project has adopted strategies such as creating and broadcasting a TV program and collaborations with manga, which are expected to have a significant impact on society. CONCLUSIONS: Compared to previous efforts on disseminating information related to health effect of radiation exposure, the "GU-GU-RU" project has taken a different approach in providing primary data of radiation and its health effects, which could become a better understanding of health effects of radiation for the general public, in order to eliminate rumors that may lead unjustified discrimination and prejudice.

Mistaken information can lead only to misguided conclusions and policies: a commentary regarding Schüz et al.'s response.

BACKGROUND: After reviewing selected scientific evidence, Schüz et al. made two recommendations in the 2018 International Agency for Research on Cancer (IARC) Technical Publication No. 46. Their first recommendation was against population thyroid screening after a nuclear accident, and the second was that consideration be given to offering a long-term thyroid monitoring program for higher-risk individuals (100-500 mGy or more radiation) after a nuclear accident. However, their review of the scientific evidence was inadequate and misrepresented the information from both Chernobyl and Fukushima. We wrote a review article published in Environmental Health in 2022 using the "Toolkit for detecting misused epidemiological methods." Schüz et al. critiqued our 2022 review article in 2023; their critique, based also on their 2018 IARC Technical Publication No. 46, was so fraught with problems that we developed this response. MAIN BODY: Schüz et al. suggest that hundreds of thyroid cancer cases in children and adolescents, detected through population thyroid examinations using ultrasound echo and conducted since October 2011 in Fukushima, were not caused by the 2011 Fukushima Daiichi Nuclear Power Plant accident. Schüz et al. compared thyroid cancers in Fukushima directly with those in Chernobyl after April 1986 and listed up to five reasons to deny a causal relationship between radiation and thyroid cancers in Fukushima; however, those reasons we dismiss based on available evidence. No new scientific evidence was presented in their response to our commentary in which we pointed out that misinformation and biased scientific evidence had formed the basis of their arguments. Their published article provided erroneous information on Fukushima. The article implied overdiagnosis in adults and suggested that overdiagnosis would apply to current Fukushima cases. The IARC report did not validate the secondary confirmatory examination in the program which obscures the fact that overdiagnosis may not have occurred as much in Fukushima. The report consequently precluded the provision of important information and measures. CONCLUSION: Information provided in the IARC Technical Publication No. 46 was based on selected scientific evidence resulting in both public and policy-maker confusion regarding past and present nuclear accidents, especially in Japan. It should be withdrawn.

Impacts of environmental decontamination on the rebuilding of returnees' lives after the Fukushima accident.

Environmental decontamination after a nuclear disaster not only contributes to reducing the public's exposure to radiation, it also introduces waste disposal issues arising from the decontamination process. In addition to that issue, the optimisation of decontamination efforts necessitates the consideration of various environmental, economic, and societal factors. Stakeholders' perspectives are important for identifying the multifaceted aspects to be considered. We conducted a semi-structured interview survey in 2019 with ten residents in a rural community in Fukushima, Japan, which experienced a six-year-long evacuation due to the 2011 Fukushima Daiichi Nuclear Power Plant accident. The main survey questions addressed returnees' perceptions of the decontamination of farmlands and forests. The 'Steps for Coding and Theorization' procedure was used for qualitative analysis. The analysis illuminated the positive and negative impacts of the decontamination process on the rebuilding of the returnees' rural lives from various perspectives and identified elements to be considered for the optimisation of future remediation efforts. The removal of radioactive materials had a positive psychological impact on the returnees, fostering a sense of security that their crops were safe and instilling confidence that the high-quality environment of the region had been restored. These aspects were not included among the initial governmental objectives for decontamination, which were aimed solely at reducing radiation exposure. By contrast, the removal of fertile topsoil from farmland had a negative impact on the residents, making them hesitant to resume farming. Our findings suggest that emphasising procedural fairness in decision-making of decontamination options such as reflection of stakeholders' opinions led to residents perceiving their post-decontamination situation more positively. Our results provide valuable insights for optimising remediation strategies for the recovery process following a significant nuclear accident.

Scientific consensus views are useful, but dangerous, without a code of ethics.

Using the Fukushima accident experience, this letter discusses recent efforts on measuring scientific consensus views-that is, quantifying the agreement among scientists. In the field of radiological protection, the efforts to measure scientific consensus views deserve attention, because hoaxes have been spreading even after the Fukushima nuclear accident. We discussed two points. First, the visualization of the diversity of scientific opinions shatters the diversity illusion caused by the mass media's irresponsible dissemination of pro and con arguments. Second, the use of scientific consensus views without an ethical code is dangerous. Measuring scientific consensus views should be accompanied with the development of ethical guidelines on using it.