Biological Approaches to the Valorization of Nuclear Wastes

The management of nuclear waste presents a complex global challenge due to the long-lived radioactivity, high toxicity, and potential for environmental contamination. Traditional physical and chemical treatment methods, while effective to some extent, often lack sustainability, incur high operational costs, and pose long-term ecological risks. In recent years, biological approaches, particularly those involving extremophilic microorganisms, biosorption, bioaccumulation, enzymatic reduction, and microbial transformation, have emerged as promising alternatives for nuclear waste valorization. This chapter explores the state-of-the-art biological techniques that not only contribute to the detoxification of radionuclides but also offer potential for resource recovery and material reuse. Focus is given to microbial species capable of surviving under extreme radiation and heavy metal stress, including Deinococcus radiodurans, Shewanella oneidensis , and metal-reducing archaea. Mechanistic insights into biotransformation of radionuclides (such as uranium, cesium, technetium, strontium, and plutonium) into less mobile or less toxic forms are presented alongside techniques like microbial-induced precipitation, biomineralization, and radionuclide bioscavenging. Advanced molecular tools, synthetic biology, and systems biology approaches are also discussed for enhancing the efficiency of microbial systems in nuclear waste environments. Real-world applications, pilot-scale studies, and potential integration with nuclear remediation strategies are reviewed. The chapter ends with a critical analysis of challenges, ethical considerations, and the road forward for safe, efficient, and sustainable biological valorization of nuclear wastes.