Papers - Nomura, Shuhei

Limited internal radiation exposure associated with resettlements to a radiation-contaminated homeland after the Fukushima Daiichi nuclear disaster.

Masaharu Tsubokura, Shigeaki Kato, Masahiko Nihei, Yu Sakuma, Tomoyuki Furutani, Keisuke Uehara, Amina Sugimoto, Shuhei Nomura, Ryugo Hayano, Masahiro Kami, Hajime Watanobe, Yukou Endo

PloS one 8 ( 12 ) e81909 2013

Accepted,  ISSN  1932-6203

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Resettlement to their radiation-contaminated hometown could be an option for people displaced at the time of a nuclear disaster; however, little information is available on the safety implications of these resettlement programs. Kawauchi village, located 12-30 km southwest of the Fukushima Daiichi nuclear power plant, was one of the 11 municipalities where mandatory evacuation was ordered by the central government. This village was also the first municipality to organize the return of the villagers. To assess the validity of the Kawauchi villagers' resettlement program, the levels of internal Cesium (Cs) exposures were comparatively measured in returnees, commuters, and non-returnees among the Kawauchi villagers using a whole body counter. Of 149 individuals, 5 villagers had traceable levels of Cs exposure; the median detected level was 333 Bq/body (range, 309-1050 Bq/kg), and 5.3 Bq/kg (range, 5.1-18.2 Bq/kg). Median annual effective doses of villagers with traceable Cs were 1.1 x 10(-2) mSv/y (range, 1.0 x 10(-2)-4.1 x 10(-2) mSv/y). Although returnees had higher chances of consuming locally produced vegetables, Cochran-Mantel-Haenszel test showed that their level of internal radiation exposure was not significantly higher than that in the other 2 groups (p=0.643). The present findings in Kawauchi village imply that it is possible to maintain internal radiation exposure at very low levels even in a highly radiation-contaminated region at the time of a nuclear disaster. Moreover, the risks for internal radiation exposure could be limited with a strict food control intervention after resettlement to the radiation-contaminated village. It is crucial to establish an adequate number of radio-contaminated testing sites within the village, to provide immediate test result feedback to the villagers, and to provide education regarding the importance of re-testing in reducing the risk of high internal radiation exposure.

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The relationship between media consumption and health-related anxieties after the Fukushima Daiichi nuclear disaster.

Amina Sugimoto, Shuhei Nomura, Masaharu Tsubokura, Tomoko Matsumura, Kaori Muto, Mikiko Sato, Stuart Gilmour

PloS one 8 ( 8 ) e65331 2013

Accepted,  ISSN  1932-6203

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BACKGROUND: The Fukushima Daiichi nuclear disaster caused a global panic by a release of harmful radionuclides. In a disaster setting, misusage of contemporary media sources available today can lead to disseminated incorrect information and panic. The study aims to build a scale which examines associations between media and individual anxieties, and to propose effective media usages for future disaster management. METHODS: The University of Tokyo collaborated with the Fukushima local government to conduct a radiation-health-seminar for a total of 1560 residents, at 12 different locations in Fukushima. A 13 item questionnaire collected once before and after a radiation-seminar was used on factor analysis to develop sub-scales for multiple regression models, to determine relationships between the sub-scales and media type consumed. A paired t-test was used to examine any changes in sub-scale of pre- and post-seminar scores. RESULTS: Three sub-scales were revealed and were associated with different media types: was with rumors, while concern for the future was positively associated with regional-newspapers and negatively with national-newspapers. Anxiety about social-disruption was associated with radio. The seminar had a significant effect on anxiety reduction for all the three sub-scales. CONCLUSION: Different media types were associated with various heightened concerns, and that a radiation seminar was helpful to reduce anxieties in the post-disaster setting. By tailoring post-disaster messages via specific media types, i.e., radio, it may be possible to effectively convey important information, as well as to calm fears about particular elements of post-disaster recovery and to combat rumors.

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Mortality risk amongst nursing home residents evacuated after the Fukushima nuclear accident: a retrospective cohort study.

Shuhei Nomura, Stuart Gilmour, Masaharu Tsubokura, Daisuke Yoneoka, Amina Sugimoto, Tomoyoshi Oikawa, Masahiro Kami, Kenji Shibuya

PloS one 8 ( 3 ) e60192 2013

Accepted

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BACKGROUND: Safety of evacuation is of paramount importance in disaster planning for elderly people; however, little effort has been made to investigate evacuation-related mortality risks. After the Fukushima Daiichi Nuclear Plant accident we conducted a retrospective cohort survival survey of elderly evacuees. METHODS: A total of 715 residents admitted to five nursing homes in Minamisoma city, Fukushima Prefecture in the five years before 11th March 2011 joined this retrospective cohort study. Demographic and clinical characteristics were drawn from facility medical records. Evacuation histories were tracked until the end of 2011. The evacuation's impact on mortality was assessed using mortality incidence density and hazard ratios in Cox proportional hazards regression. RESULTS: Overall relative mortality risk before and after the earthquake was 2.68 (95% CI: 2.04-3.49). There was a substantial variation in mortality risks across the facilities ranging from 0.77 (95% CI: 0.34-1.76) to 2.88 (95% CI: 1.74-4.76). No meaningful influence of evacuation distance on mortality was observed although the first evacuation from the original facility caused significantly higher mortality than subsequent evacuations, with a hazard ratio of 1.94 (95% CI: 1.07-3.49). CONCLUSION: High mortality, due to initial evacuation, suggests that evacuation of the elderly was not the best life-saving strategy for the Fukushima nuclear disaster. Careful consideration of the relative risks of radiation exposure and the risks and benefits of evacuation is essential. Facility-specific disaster response strategies, including in-site relief and care, may have a strong influence on survival. Where evacuation is necessary, careful planning and coordination with other nursing homes, evacuation sites and government disaster agencies is essential to reduce the risk of mortality.

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The voice of the most vulnerable: lessons from the nuclear crisis in Fukushima, Japan

A. Sugimoto, S. Krull, S. Nomura, T. Morita, M. Tsubokura

BULLETIN OF THE WORLD HEALTH ORGANIZATION (WORLD HEALTH ORGANIZATION)  90 ( 8 ) 629 - 630 2012.08

Accepted,  ISSN  0042-9686

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