Investigation of I-125 Uptake in Five Different Plants

Background: Radioiodine 125I is an environmental contaminant that humans may consume in edible plants. The characteristics of 125I in plants are poorly understood. Objectives: This study examined 125I concentrations in the edible parts of five types of plants from different locations on farms with a similar climate. Near Zahedan, Iran. Materials and Methods: The experiments used a mini-column approach in which more realistic conditions than those of the batch-sorption technique were maintained. Twenty sub-samples from the leaves and stems of five different plants (sugar beet, turnip, alfalfa, oat and bamboo) were obtained, and 445 Bq of 125I was added to the plants. Results: Immediately, and after one month, 500 g of each wet plant sub-sample was placed in a test tube, and the 125I contents of the stem and leaves were measured for 20 s by a gamma ray counting machine. The 125I concentration either increased or was reduced in the edible parts of the plants. More radioactive adsorption occurred in the leaves than in the stems in all cases. Conclusion: Radioiodine concentrations depended upon the type of plant. Such knowledge of the physicochemical characteristics of radioiodine adsorption in plants is essential for estimating the behavior of the iodide group, especially the transfer of 129Ito other systems.