Concentration of radiocaesium in rice and irrigation water, and soil management practices in Oguni, Date, Fukushima

The concentration of radiocaesium ( 134 Cs and 137 Cs) in brown rice collected from Oguni, Date, Fukushima in 2011 was over 500 Bq kg −1 , which was the provisional regulation value in 2011, and rice cultivation was prohibited in 2012. Rice culture was resumed following the application of K fertilizer as a countermeasure in 2013. The concentration of 137 Cs in soils and irrigation water in 2013 was in the range of 1200 to 4000 Bq kg −1 ( n  = 31) and 0.078 to 1.1 Bq L −1 ( n  = 7), respectively. The concentration of 137 Cs in the dissolved fraction in irrigation water filtered with 0.45 µm pore‐size membrane filter was a relatively constant at 0.019 to 0.038 Bq L −1 ( n  = 7). The concentration of 137 Cs in brown rice cultivated in the paddy fields after implementing the countermeasure was 1.1 to 24 Bq kg −1 dry weight ( n  = 29), which was lower than the Standard Limits (100 Bq kg −1 ). However, the concentration of Cs in rice cultivated under a similar agricultural management as in 2011 and prior to the Tokyo Electric Power Company Holdings' (TEPCO) Fukushima accident was over the Standard Limits. Integr Environ Assess Manag 2016;12:659–661. © 2016 SETAC