Towards a Long-Term Strategy for Voluntary-Based Internal Radiation Contamination Monitoring: A Population-Level Analysis of Monitoring Prevalence and Factors Associated with Monitoring Participation Behavior in Fukushima, Japan

Comparative risk assessment of non-communicable diseases by evacuation scenario- a retrospective study in the 7 years following the Fukushima Daiichi nuclear power plant accident

Background: As a result of the Fukushima Daiichi nuclear power plant accident, many residents evacuated and were exposed to changes in their living environment and socioeconomic status, and to persistent stressors. Past studies have suggested the potential for these circumstances to contribute to long-term changes to population health.Objective: The objective of this study was to gain a better understanding of long-term health effects of evacuation, by evaluating the risk of non-communicable diseases among evacuees from Minamisoma City (one of the closest municipalities to the power plant) until 2017.Methods: The study evaluated data from annual health check-ups for residents aged 40-74 years covered by National Health Insurance (who are largely self-employed) from 2010 to 2017 administered by Minamisoma City. Diabetes, hyperlipidemia, and hypertension were defined from the results of blood sampling. Annual changes in age-adjusted prevalence were estimated by evacuation scenario. We also performed an inverse-probability weighting (IPW) analysis to adjust for baseline covariates in 2010 and estimated the differences in the risk of diabetes, hyperlipidemia, and hypertension by evacuation scenario as of the 2017 health check-up in reference to the no-evacuation group.Results: A total of 1,837 individuals were considered in this study. Regardless of evacuation scenario, there was statistical evidence suggesting an upward and a downward trend in diabetes and hypertension from 2010 to 2017, respectively, while hyperlipidemia showed no remarkable change. IPW analyses demonstrated that disease risks in 2017 did not differ significantly among people with different evacuation scenarios.Conclusions: Region-specific factors played an important role in the health effects of the evacuation. Our findings have important implications for the need of an assessment of the health effects of evacuations in more localized manner. Further research in this area will strengthen the communities' preparedness for future disasters that require mass evacuation.

Usefulness of the whole-body counter for infants and small children (BABYSCAN) as a risk communication tool after the Fukushima Daiichi nuclear power plant incident

Responding to the radiation-related concerns of parents/guardians with infants/small children is an important public health issue for regional recovery after radioactive contamination. This study summarizes the results of a systematic internal contamination screening of infants/small children, aged 0-6 years, using BABYSCAN and individual counselling sessions with physicians about radiation concerns from 2014 to 2018 in Minamisoma City. Of 3,114 participants, no one was found to have internal contamination with radioactive caesium with a detection limit of 50 Bq/body. The questionnaire survey showed a decreasing trend of concerns about food contamination and playing outside as possible causes of internal contamination over time. Because people's concerns were diverse in counselling sessions, individual responses are required. This study showed that examinations using BABYSCAN provide an opportunity for direct dialogue between the parents/guardians of infants/small children and experts. This can be considered a model case for risk communication conducted by the local government after a radioactive contamination incident.

High internal radiation exposure associated with low socio-economic status six years after the Fukushima nuclear disaster: A case report

RATIONALE

Managing the health of vulnerable groups is an important component of health care. Given the long-term burden of radiation-release incidents among those exposed, managing the health of vulnerable groups following a nuclear disaster is very important. However, there is limited information available concerning the long-term management of the health effects of radiation exposure in vulnerable groups following nuclear disasters. After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, Minamisoma City launched internal radiation exposure monitoring program for local residents, using whole body counter (WBC) units. In 2017, a man of low socio-economic status (SES), was found to have the highest level of internal contamination detected in a person living in the Soma District in recent years. This report describes the case so that the lessons learned can be applied in future nuclear disaster settings.

PATIENT CONCERNS

A 77-year-old Japanese man, who had been homeless for 2 months and had been staying in the exclusion zone of Minamisoma City, was brought to our hospital. He had become homeless because a lack of communication between social support services had led to his eviction from leased housing after free housing support for evacuees was terminated.

DIAGNOSES

He was admitted with a diagnosis of dehydration and malnutrition. A WBC unit was used to assess his body burden of radioactive cesium. This revealed levels of Cs-134 and Cs-137 of 538 Bq/body and 4,993 Bq/body, respectively.

INTERVENTION

He received intravenous fluid therapy and health monitoring. The paperwork required for him to receive public income support was processed during hospitalization.

OUTCOME

He was discharged to public housing after 9 days, and municipal workers started visiting him regularly after his discharge.

LESSONS

A high level of internal radiation contamination may occur after a nuclear disaster. This may be associated with a decline in social support, poverty, and social isolation, and may have more impact on people in poor health than on the general population. It would be useful to strengthen linkages between local government and welfare service providers to increase social support for vulnerable groups requiring health care, not only following disasters, but also under normal circumstances.

Internal exposure risk due to radiocesium and the consuming behaviour of local foodstuffs among pregnant women in Minamisoma City near the Fukushima nuclear power plant: a retrospective observational study

OBJECTIVES

This study aimed to evaluate the internal cesium (Cs) level among pregnant women in Minamisoma City (the area straddling the evacuation zones) over a 5-year period after Japan's 2011 Fukushima nuclear accident and assess the status and transition of their food-acquiring preferences during this period.

DESIGN

A retrospective observational study of a screening along with a questionnaire survey.

SETTING

This study was conducted in an obstetrics and gynaecology service in Minamisoma City in Fukushima, Japan.

PARTICIPANTS

Participants included pregnant women who applied for the voluntary internal radiation exposure screening programme.

PRIMARY AND SECONDARY OUTCOME MEASURES

Internal radiation exposure was evaluated using the whole-body counter (WBC) in the screening programme. Data from a food acquisition preference questionnaire administered to the participants were analysed and compared across the 5-year period after adjusting for covariates.

RESULTS

Overall, 804 screening programmes were conducted with 579 participants during the study period. All participants had internal contamination levels below the detection limit of the WBC unit (220 and 250 Bq/body for Cs-134 and Cs-137, respectively). Based on the most conservative assumption, their maximum annual effective doses by Cs-134 and Cs-137 together were estimated at 16 µSv/year. Contrary to limited internal contamination risks and counter-dose initiatives by the government, a considerable number of pregnant women were still concerned about consuming potentially contaminated local food products when purchasing them at supermarkets between 2012 (78.4%) and 2015 (75.0%).

CONCLUSIONS

Health effects from post-accident internal radiation exposure were likely to be insignificant in pregnant women. National/local action is urgently needed to promote scientific understanding in pregnant women regarding limited internal exposure risks from local food products in the market. However, few mothers chose to participate in the internal radiation exposure screening programme, and thus, caution is required in interpreting the results of analyses.

The Great East Japan Earthquake, Tsunamis, and Fukushima Daiichi Nuclear Power Plant Disaster: Lessons for Evidence Integration from a WADEM 2017 Presentation and Panel Discussion

In April 2017, some of the health impacts of the 2011 Great East Japan Earthquake, tsunamis, and resultant Fukushima Daiichi nuclear power plant disaster (Okuma, Fukushima Prefecture, Japan) were presented at the 19th Congress of the World Association for Disaster and Emergency Medicine (WADEM; Madison, Wisconsin USA) in Toronto, Canada. A panel discussion was then opened by asking audience members about their experiences in their own countries, and how they would suggest taking steps to reach the goals of the Sendai Framework for Disaster Risk Reduction 2015-2030. This paper summarizes the presentation and panel discussion, with a particular focus on the common problems identified in understanding and reducing health risks from disasters in multiple countries, such as the ethical and practical difficulties in decision making on evacuating vulnerable populations that arose similarly during the Fukushima nuclear disaster in 2011 and Hurricane Ike's approach to Galveston (Texas USA) in 2008. This paper also highlights the need for greater integration of research, for example through increased review and collation of evidence from different disaster settings to identify common problems and possible solutions, which was identified in this panel session as a precursor to fulfilling the goals of the Sendai Framework.Leppold C, Ochi S, Nomura S, Murray V. The Great East Japan Earthquake, tsunamis, and Fukushima Daiichi nuclear power plant disaster: lessons for evidence integration from a WADEM 2017 presentation and panel discussion. Prehosp Disaster Med. 2018;33(4):424-427.

The Fukushima Daiichi Nuclear Power Plant accident and school bullying of affected children and adolescents: the need for continuous radiation education

The health threats of radiation-release incidents are diverse and long term. In addition to direct radiation effects, it is imperative to manage the indirect effects of radiation such as stigma, prejudice and broader mental health impacts. Six years after the Fukushima Daiichi Nuclear Power Plant accident of March 2011, bullying caused by stigma and prejudice toward evacuees, including children, has become a social problem in Japan. This phenomenon may be associated with the fact that knowledge about radiation has still not reached the general public, and to a potential lack of motivation among Japanese citizens to learn about radiation and bullying. Continuous and sustained education regarding radiation is warranted in order to enhance the general knowledge level about the effects of radiation in Japan after the Fukushima Daiichi Nuclear Power Plant accident, and this education will become an important reference for education after future nuclear disasters.

Social Capital Enhanced Disaster Preparedness and Health Consultations after the 2011 Great East Japan Earthquake and Nuclear Power Station Accident

After the Great East Japan Earthquake and the subsequent Fukushima Daiichi Nuclear Power Station accident in 2011, there was a strong demand to promote disaster preparedness approaches and health checkups for the prevention of lifestyle diseases. This study examined the yearly change in the percentage of those who prepared for disasters and who utilized health checkups in Fukushima Prefecture, and identified the factors governing disaster preparedness and utilization of health checkups. We used the public opinion survey from 2011 to 2015 (n = 677–779 each year) on prefectural policies that is conducted every year by the Fukushima Prefecture government Public Consultation Unit. We found that the percentage of those who prepare for disasters decreased, while that for health checkups did not significantly change. With regard to disaster preparedness, experiences of disaster enhance disaster preparedness, while bonds with other local people help to maintain preparedness. For health checkups, familiarity with the welfare service was the most important factor governing such consultations. The findings suggest that social capital should be promoted in order to improve disaster preparedness. The findings also suggest that residents’ accessibility to medical and welfare services is also important in promoting the utilization of health checkups.

Towards a Long-Term Strategy for Voluntary-Based Internal Radiation Contamination Monitoring: Representativeness of the Monitoring Results in Fukushima, Japan

Following Japan's 2011 Fukushima nuclear incident, voluntary participation, rather than mandatory, was adopted as the default scenario for individual radiation monitoring. We evaluated the representativeness of the internal monitoring results from voluntary participants in Minamisoma City, which is located 10-40 km from the Fukushima nuclear plant. Of approximately 70,000 individuals who were residing in Minamisoma City before the incident, a total of 19,263 residents (aged ≥21 years) participated in the monitoring from 1 October 2011 to 31 March 2015. Based on regression projection techniques with the available data obtained from the voluntary participants, the modeled probabilities of radiocesium (Cs) detection in October 2011 for Cs-137 and Cs-134 were 66.9% and 52.9%, respectively, which declined dramatically within a year following the incident. The rate of decline had stagnated since mid-2012, and the probability was close to zero after mid-2014. Sufficient agreement between the modeled probabilities of Cs detection (for the whole population) versus the measured Cs levels (for voluntary participants) was observed, except for Cs-134 in October 2011, indicating that the voluntary monitoring participant group was a good representative sample. Our findings affirmed the clinical importance of voluntary-based monitoring as a screening and dose-assessment tool in a post-nuclear incident. Our study informs societal decision-making regarding the long-term maintenance of the monitoring program under the current low exposure levels.