Department of Global Health, Medicine and Welfare, Atomic Bomb Disease Institute, Nagasaki University , Nagasaki, Japan.
Environ Sci Technol. 2014 Apr 15;48(8):4556-63. doi: 10.1021/es404534y. Epub 2014 Mar 26.
The external and internal exposure doses due to artificial radionuclides after the return of residents to their homes in Kawauchi Village, Fukushima Prefecture, including the restricted area within a 20-km radius from the Fukushima Dai-ichi Nuclear Power Plant (FNPP), were evaluated by gamma spectrometry of the soils and local agricultural products. The prevalent dose-forming artificial radionuclides from all samples were determined to be (134)Cs and (137)Cs (radiocesium). The estimated external effective doses from soils sampled on December 24 and 25, 2012 were 0.0017-9.2 mSv/y in the areas within a 20- to 30-km radius from the FNPP and 0.39-1.3 mSv/y in the areas within a 20-km radius from the FNPP. These levels appeared to be decreasing, despite the distance from the FNPP (median: 0.21 (0.012-0.56) mSv/y), compared to the levels just before the return of the residents to their homes on December 19 and 20, 2011 (median: 0.85 (0.40-1.4) mSv/y). The committed effective doses from the local agricultural samples in Kawauchi Village from May 1, 2012 to March 31, 2013 were sufficiently low, in the range of 18-44 μSv/y for males and 20-48 μSv/y for females (the range was 18-48 μSv/y for children and 25-43 μSv/y for adults), compared to the public dose limit (1 mSv/y, ICRP, 1991), although the potential for radiation exposure still exists. Residents who have not yet returned may be able to return to their homes with a long-term follow-up of environmental monitoring and countermeasures to reduce unnecessary radiation exposure.
对福岛县川内村居民返回家园后（包括福岛第一核电站 20 公里半径范围内的限制区域），以及来自福岛第一核电站外部和内部的人工放射性核素的辐射剂量，通过对土壤和当地农产品进行伽马能谱测量进行了评估。从所有样本中发现的主要致辐射人工放射性核素为 (134)Cs 和 (137)Cs（放射性铯）。2012 年 12 月 24 日和 25 日采集的土壤样本的估计外照射有效剂量，在距离福岛第一核电站 20-30 公里的区域为 0.0017-9.2 mSv/y，在距离福岛第一核电站 20 公里的区域为 0.39-1.3 mSv/y。尽管与福岛第一核电站的距离（中位数：0.21（0.012-0.56）mSv/y）有所不同，但与 2011 年 12 月 19 日和 20 日居民返回家园之前的水平相比，这些水平似乎在下降（中位数：0.85（0.40-1.4）mSv/y）。从 2012 年 5 月 1 日至 2013 年 3 月 31 日，在川内村采集的当地农产品的集体有效剂量足够低，男性为 18-44 μSv/y，女性为 20-48 μSv/y（儿童为 18-48 μSv/y，成人 25-43 μSv/y），与公众剂量限值（1 mSv/y，ICRP，1991）相比，尽管仍然存在辐射暴露的风险。尚未返回的居民可以在对环境进行长期监测和采取减少不必要辐射暴露的对策的情况下返回家园。
