UPTAKE OF 137Cs AND 90Sr IN RICE PLANTS

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 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 areal transfer factors 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 areal transfer factors were also analyzed for their dependence on soil characteristics, time and duration of the contamination. The areal transfer factors obtained in this study refer to the absorption of the fallout nuclides deposited in the irrigation water in a rice field as opposed to other studies that deal with uniform activity concentration in the soils.

Plant uptake and downward migration of 85Sr and 137Cs after their deposition on to flooded rice fields: lysimeter experiments with and without the addition of KCl and lime

“…A solution to the problem is to use the areal transfer factor (TF a , m 2 kg ÿ1 ), which is based on the unit-area deposition (Bq m ÿ2 ) at different growth stages. The term, areal transfer factor, is cited from Leung and Shang (2003).…”

“…Almost nothing is reported about the TF a values for rice except for the works of Choi et al (1995); Choi et al (2002a) and Leung and Shang (2003).…”

Uptake, retention and organ/tissue distribution of 137Cs by Japanese catfish (Silurus asotus Linnaeus)

“…After the Chernobyl accident, there was further interest . Owing to its chemical and physiological similarity with potassium, 137 Cs can easily enter into the food chain and become an important contributor to internal radiation dose of animal bodies Leung and Shang, 2003).…”

Transfer of 137Cs and 40K from Agricultural Soils to Food Products in Terrestrial Environment of Tarapur, India

“…A similar type of transfer factor determination work has been carried out by Beresford and Howard (1991) and El-Reefy et al (2006) where they have used unwashed vegetables/ grass which were fed to animals and thus can be compared with the present study. Leung and Shang (2003) reported that stem and leaves accumulate most of the 137 Cs compared to rice seed which carries the least concentration of 137 Cs. It was observed that transfer factor for 40 K was found to be >1 and that of 137 Cs was <1.…”