Bridging a gap: Analyzing radioactive materials within the planetary boundary framework

Human activities are inherently embedded into the environment and must stay within the limits of our planet. Nuclear power is highlighted as a low-carbon technology to mitigate climate change by industry and sometimes by academia and in politics. From a system perspective, it is inevitable to shed light on the accumulation of long-lived and hazardous radioactive materials stemming from the operation of nuclear power plants. Only recently, the planetary boundary (PB) framework (re-)emphasized radioactive material but without further investigation. This paper aims to bridge this conceptual gap by conceptualizing human-made radioactive materials into the PB framework. We first review the development of the PB concept, emphasizing the novel entities boundary, and summarize previous approaches and variables. We then argue for a planetary perspective on radionuclides as a concern, proposing their inclusion as a sub-boundary within the novel entities PB. Therefore, this paper specifies “anthropogenically mobilized radioactive materials”, proposes potential control variables, and provides the first detailed analysis in this context. We conclude by discussing the implications of the precautionary principle and the concept of a “safe operating space” for radioactive materials to address radioactive materials in the global sustainability context.