Bioremediation of ⁶⁰Co from simulated spent decontamination solutions of nuclear power reactors by bacteria

The spent decontamination solutions generated from nuclear power reactors contain radionuclides of cobalt (⁶⁰Co, ⁵⁶Co and ⁵⁷Co) along with a large excess (10⁵) of non-radioactive metal ions (Fe, Ni and Cr). Our previous studies demonstrated that bioremediation of ⁶⁰Co from simulated effluents using fungal biomass can provide an alternative to conventional ion exchangers. In this study, we used several bacteria to further improve the process of bioremediation by decreasing biomass requirement and treatment period. Further, metabolite activation in specific bacterial species resulted in enhanced bioremediation of ⁶⁰Co from simulated effluent. Optimization of conditions in simulated effluent for the eight bacterial species to accomplish maximum ⁶⁰Co removal is discussed.