Distribution of radionuclide in Cauvery River Basin, South Interior Karnataka, India

Radium, radon and polonium are the most important isotopes from the radiological point of view in the uranium decay series. The concentrations of radium, radon and polonium were studied in water samples of Kodagu, Mandya, Mysuru, Hassan and Chamarajanagara districts. The study area lies between 10°05'N to 13°30' N latitudes and 75°30' E to 79°45' E longitudes. Polonium in water was estimated using radiochemical analysis. Higher concentration of polonium in water was observed at Kushalnagara region (3.35 mBqL^-1), lower value was found near Mysuru (1.54 mBqL^-1) -and the average polonium concentration in the study region was (2.49 mBqL^-1). The radium-226 was analysed using Emanometry method. Higher concentration of radium-226 was found near Abbi falls of Kodagu district (73.0 mBqL^-1), lower value was found in Srirangapatna of Mandya district (2.20 mBqL^-1) and the average was 36.12 mBqL^-1. W.H.O and UNSCEAR have given the tolerable dose range for different radioactive elements. If the estimated value crosses this range then it would cause certain health hazards. The values obtained in the present study are comparable to the value of polonium, radium and radon in water reported in literature. (author)