Different ²¹²Pb Generators and Its Radiation Safety Concerning ²²⁰Rn (Thoron) Emanation

(1) Background: As the demand for ²¹²Pb for clinical theranostics rises, empirical studies that examine the radiation safety implications of different ²²⁴Ra sources are needed to facilitate discussions with local authorities for the translation of ^203/212Pb theranostics routine clinical practice. (2) Methods: Environmental ²²⁰Rn (Thoron) emanation was detected by a RAD7 detector in the vicinity of respective ²¹²Pb sources and additional alpha-dosimeters to detect ²²⁰Rn during generator elution, radiosynthesis, and quality control. Personnel gamma exposure was measured using whole-body and ring dosimeters. Generators included those based on wet-chemical-process- and emanation-based technology. (3) Results: During generator handling, varying levels of ²²⁰Rn were observed in the vicinity of generators. An additional monthly whole-body dose must be considered when handling different sources of ²¹²Pb generators, and this depends upon local shielding and the handling approaches toward use of the technology. (4) Conclusions: ²²⁴Ra in any form (including radionuclide generators) should always be handled within a fume hood to keep potential contamination and exposure to personnel as low as reasonably achievable. Following standard practices of radiation safety, generators of ²¹²Pb can be used safely for theranostic applications.