Disequilibrium of uranium series radionuclides in soil and plants of South India

Soil and plants of South India were analysed using standard methods for equilibrium state between radionuclides ²²⁶Ra, ²¹⁰Pb, and ²¹⁰Po of uranium series. A disequilibrium state was observed, with mean ²¹⁰Pb/²²⁶Ra, ²¹⁰Po/²²⁶Ra, and ²¹⁰Po/²¹⁰Pb as 21.71, 5.52, and 0.40; 10.01, 4.21, and 0.43; and 30.86, 9.34, and 0.35 in Coastal Karnataka, Malnad Karnataka, and Malnad Kerala, respectively. ²¹⁰Po/²¹⁰Pb in soil was 0.29, 0.30, and 0.49 respectively, for the three regions. Unsupported ²¹⁰Pb and ²¹⁰Po might have caused the observed disequilibrium state. The investigation helps to monitor radionuclide distribution and dynamics in soil and plants of the study area. (author)