Small-scale theranostic radiopharmaceutical production using cold kits: a green chemistry perspective.

The global rise of theranostic nuclear medicine continues to increase the environmental and economic pressure associated with radiopharmaceutical production. Large-scale manufacturing, reliant on cyclotrons, GMP-compliant cleanrooms, automated synthesis modules, and disposable plastics, represent the most energy-intensive and waste-generating approach. In contrast, cold kit technologies represent an underutilized strategy to improve sustainability, reduce environmental impact and expand equitable global access to theranostic radiopharmaceuticals. This review evaluates small-scale hospital-based compounding using lyophilised cold kit technologies through the lens of green chemistry and environmental justice. Gallium-68 and lutetium-177 are used as representative theranostic radionuclides. Energy consumption, waste generation, and accessibility between large-scale and hospital-based production are considered, highlighting the reduced environmental footprint of cold kits. Attention is given to radionuclide waste streams, including long-lived contaminants such as germanium-68 and lutetium-177 m. Challenges associated with cold kit production, including radionuclide source variability, radiochemical robustness and occupational radiation protections are addressed. This review indicates that small-scale hospital compounding could contribute to a more sustainable, resource-efficient, and equitable nuclear medicine practice without compromising clinical quality or patient safety.