〔フクイチ・グローバル核惨事〕◆ フクイチ発のヨウ素１３１プルーム、（２０１１年）３月２３日に米南部、ミシシッピーに到着 ４月１９日まで襲来、続く / 雨で降下、平方メートルあたり４．６ベクレル /鉛２１０、ポロニウム２１０とともに / ＮＡＳＡ（米航空宇宙局）のステニス宇宙センター（南ミッシシッピー大学）の研究者らが２０１２年４月、国際学術誌、『環境放射能ジャーナル』に発表 ★ 米南部での甲状腺被曝が心配される！

　★　フクイチ発の放射性ヨウ素・プルームは、２０１１年３月２２日、米南部フロリダ州にも到達、現地の原発モニタリングポストで検知されている。
　⇒　http://onuma.cocolog-nifty.com/blog1/2014/11/1220-pcikg-wet-.html

　　　　　　　　　　*

　★　ミシシッピーなど米南部では、甲状腺障害が出ていないのだろうか？

　　　　　　　　　　*

  〔★は大沼〕◎　Journal of Environmental Radioactivity　：　Depositional fluxes and residence time of atmospheric radioiodine (131I) from the Fukushima accident
　 Weifeng Yang（Department of Marine Science, University of Southern Mississippi, 1020 Balch Blvd., Stennis Space Center, MS 39529, USA）
　 Laodong Guo（College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China）
　⇒　http://www.researchgate.net/c/nqk6qv/javascript/lib/pdfjs/web/viewer.html?file=http%3A%2F%2Fwww.researchgate.net%2Fprofile%2FWeifeng_Yang3%2Fpublication%2F225058032_Depositional_fluxes_and_residence_time_of_atmospheric_radioiodine_%2528I-131%2529_from_the_Fukushima_accident%2Flinks%2F02e7e516ea8282475f000000.pdf%3FdisableCoverPage%3Dtrue

　　　　　　　　　　*　

・　abstract

　Activities of radioiodine (131I) along with 210Pb and 210Po in time series precipitation samples were measured to determine the depositional fluxes of
131I in the Southern United States and its removal rate and residence time in the atmosphere during the Fukushima nuclear accident. Radioiodine released from the Fukushima accident reached the Southern United States within 11 days, giving rise to a concurrent 131I peak and anomalous 210Po/210Pb ratios in the precipitation samples. The cumulative 131I depositional flux was 4.6±
0.2 Bq m2 during the maximum fallout.

・These results support our  hypothesis that radioiodine was removed from the atmosphere by precipitation within two weeks. It seemed that regions reachable by 131I transport within two weeks from Fukushima Japan would receive much more fallout, whereas places outside that distance would be relatively less polluted with radionuclides.

　　　　　　　　　　*

　. Results and discussion　3.1.

　131I deposition and activities

　Following the Fukushima accident, a high level of 131I was first detected on March 23 in a dry deposition sample at the SSC, Mississippi with a depositional flux of 232 mBq m2d1 . After this initial fallout, the 131I depositional flux increased up to ten- to twenty-fold during the following two weeks, varying from 218±18 mBq m2d1 to 463±16 mBq m2d1. However,the
131I abundance became nearly undetectable after April 19, 2011.

　　　　　　　　　　*

　・　4. Conclusions

Iodine-131, released from the Fukushima nuclear accident, was transported to the southern United States within 11 days. Wet precipitation was the main removal pathway of atmospheric 131I in addition to its decay, resulting in a detectable 131I activity in surface waters. The majority of 131 I in the atmosphere was removed in about two weeks after the Fukushima accident.