Understanding The Biological Effects of Thorium and Developing Efficient Strategies for Its Decorporation and Mitigation

Due to limited sources of natural uranium, Department of Atomic Energy (DAE) has sought thorium (Th) as an alternative source of nuclear fuel. India has one of the largest deposits of natural Th in the form of monazite in Kerala. The currently known Indian Th reserves amount to 155,000 GWe-yr of electrical energy and can meet the energy requirements during the next century and beyond. Thorium-232 (232Th) is the major isotope and constitutes ~9% of monazite. Development of advanced heavy water reactor (AHWR) and fast breeder reactor (FBR) technologies in combination with pressurized heavy water reactor (PHWR) would enable the use of non-fissile 232Th for the generation of fissile element, uranium-233 (U-233). This three stage-Indian nuclear program would meet the goal of self-sustainable energy security in India. In views of increasing realization of 232Th in India, research activities were undertaken to achieve all round capability in the development of safe and ecofriendly thorium fuel cycle (Table 1).