Division of Social Communication System for Advanced Clinical Research, Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo, Japan ; Department of Radiation Protection, Soma Central Hospital, Soma, Fukushima, Japan ; Hirata Radioactivity Inspection Center, Hirata Central Hospital, Hirata, Fukushima, Japan.
PLoS One. 2013 Dec 2;8(12):e81909. doi: 10.1371/journal.pone.0081909. eCollection 2013.
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.
返回家乡可能是核灾难发生时流离失所者的一种选择；然而，关于这些安置计划的安全影响的信息很少。川内村位于福岛第一核电站西南 12-30 公里处，是中央政府下令强制撤离的 11 个市町村之一。这个村也是第一个组织村民返回的市町村。为了评估川内村村民安置计划的有效性，使用全身计数器比较测量了川内村返回者、通勤者和非返回者体内内部铯（Cs）暴露水平。在 149 人中，有 5 名村民的 Cs 暴露水平可检测到；检测到的中位数水平为 333 Bq/体（范围为 309-1050 Bq/kg），5.3 Bq/kg（范围为 5.1-18.2 Bq/kg）。可检测到 Cs 的村民的年平均有效剂量为 1.1 x 10(-2) mSv/y（范围为 1.0 x 10(-2)-4.1 x 10(-2) mSv/y）。尽管返回者更有可能食用当地生产的蔬菜，但 Cochran-Mantel-Haenszel 检验表明，他们体内辐射暴露水平与其他两组没有显著差异（p=0.643）。川内村的研究结果表明，即使在核灾难发生时，在高度辐射污染的地区，也有可能将内部辐射暴露保持在非常低的水平。此外，通过在返回受辐射污染的村庄后进行严格的食品控制干预，可能会限制内部辐射暴露的风险。在村庄内建立足够数量的放射性污染检测点，为村民提供即时的检测结果反馈，并提供有关重新检测在降低高内部辐射暴露风险方面的重要性的教育，这一点至关重要。
