Monitoring and analysis of the internal exposure of 131I-treatment workers in Nuclear-Medicine Departments in Jiangsu Province from 2021 to 2023

Herein, we analyze the dose distribution and factors influencing the occupational internal irradiation exposure to iodine-131 (131I) for nuclear-medicine staff in Jiangsu Province. A total of 472 individuals in 56 hospitals were monitored during the three-year monitoring period, and 131I was detected in 170 of them. The highest thyroid activity level detected across all cases was 24.83 kBq, with the average thyroid activity being 130.3 Bq. The average annual dose of irradiated staff members was 0.339 mSv. The primary factors related to the detection rate of 131I in the irradiated staff members were their work position, their location, the operation of an automatic dispenser, and their weekly working hours. Internal exposure thus requires due attention, and further effective monitoring of internal exposure should be conducted for all such staff members.