- 著者
- Kazuhiro Shiba Yoji Kitamura Takashi Kozaka Izumi Uno Kikuo Shimizu Masahiro Hirota Shogo Higaki Kazuyoshi Masumoto
- 出版者
- 日本放射線安全管理学会
- 雑誌
- Radiation Safety Management (ISSN:13471511)
- 巻号頁・発行日
- vol.11, no.1, pp.19-22, 2012 (Released:2012-12-21)
- 参考文献数
- 5
- 被引用文献数
- 1
We examined the characteristics of the radioactive contamination and the physical removal of radioactivity from contaminated cabbage and spinach. In a distribution imaging study, there were two types of contamination, spot type and spread type, of cabbage and spinach. The relative radioactivity (PSL) of the face of the leaf was much higher than that of the back of a leaf of cabbage. The ratio of relative radioactivity (PSL) between spot contamination and spread contamination in a leaf of spinach was 9.4% and 90.6%, respectively. More than 80% of radioactivity attaches to the surface of leaves of spinach. There was no significant difference of radioactivity removal between hand-washing and rinsing with running water. The degree of removal of radioactivity from contaminated spinach depended on the length of time between contamination and rinsing. When contaminated spinach was rinsed within 1 week after contamination, the removal ratio of 131I and 137Cs was high, with 50% and 70%, respectively. When rinsing contaminated spinaches more than 2 weeks after contamination, the removal ratio of 131I and 137Cs was low, approximately 34% and 69%, respectively.
- 著者
- Kazuhiro Shiba
- 出版者
- 日本放射線安全管理学会
- 雑誌
- Radiation Safety Management (ISSN:13471511)
- 巻号頁・発行日
- vol.12, no.1, pp.31-36, 2013 (Released:2013-04-12)
- 参考文献数
- 2
- 被引用文献数
- 1 1
Huge amounts of radioactivity derived from the Fukushima nuclear accident were scattered in the atmosphere. Various kinds of vegetables in three prefectures in the Tohoku area were contaminated with 131I and 137Cs over the legal limit for shipment. A simple and effective removal method for contaminated farm products was developed to ensure the relief of farmers and the security of consumers. Distribution imaging of radioactivity in the contaminated vegetables, the physical removal of radioactivity from contaminated vegetables and the chemical removal of radioactivity from contaminated vegetables were examined. As a result, there were two types of vegetable contamination, spot type or spread type. The concentration of radioactivity was higher on the outer side than the inner side of a vegetable leaf. More than 80% of radioactivity attaches to the surface of leaves. Radioactivity removal by water washing showed no significant difference between boiling water and cold water. There was no significant difference between hand-washing and running water washing. The radioactivity of vegetables decreased by 70-80% for 131I and more than 80% for 137Cs by reducing agent treatments. In particular, ascorbic acid is promising as a safe and versatile option.