Bioaccumulation of 226Ra by plants growing in fresh water ecosystem around the uranium industry at Jaduguda, India

A field study has been conducted to evaluate the Ra-226 bioaccumulation among aquatic plants growing in the stream/river adjoining the uranium mining and ore-processing complex at Jaduguda, India. Two types of plant group have been investigated namely free floating algal species submerged into water and plants rooted in stream & riverbed. The highest Ra-226 activity concentration (9850 Bq kg(-1)) was found in filamentous algae growing in the residual water of tailings pond. The concentration ratios of Ra-226 in filamentous algae (activity concentration of 226Ra in plant Bq kg(-1) fresh weight/activity concentration of Ra-226 in water Bq l(-1)) widely varied i.e. from 1.1 x 10(3) to 8.6 x 10(4). Other aquatic plants were also showing wide variability in the Ra-226 activity concentration. The ln-transformed filamentous algae Ra-226 activity concentration was significantly correlated with that of ln-transformed water concentration (r = 0.89, p < 0.001). There was no correlation between the activity concentrations of Ra-226 in stream/ riverbed rooted plants and the substrate. For this group, correlation between Ra-226 activity concentration and Mn, Fe, Cu concentration in plants were statistically significant. (C) 2010 Elsevier Ltd. All rights reserved.