Uptake of ¹³⁷Cs and ⁹⁰Sr in rice grown on soils from Qinshan and Daya Bay area

Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong

Abstract

In order to study the transfer of water borne ¹³⁷Cs and ⁹⁰Sr into rice plants, pot experiments were done by growing rice plants on soils taken from rice beds near two nuclear power plants : Qinshan Nuclear Power Plant and Daya Bay Nuclear Power Plant in China. The vertical migration of ¹³⁷Cs and ⁹⁰Sr in the soil samples due to leaching was studied, and results show that almost all the contaminants were retained in the top 1 cm of soil, with at most a few percent down to 3 cm of soil. The transport factors (TF) of ¹³⁷Cs and ⁹⁰Sr were studied by adding various activity concentrations of the two radionuclides to the irrigation water and then measuring the activity concentration in the various rice tissues. The TF were also analysed for their dependence on soil characteristics, time and duration of the contamination.