Evaluation of exposure characteristics and radiological risks for cyclotron-based F radiopharmaceutical production workers in China.

[BACKGROUND] The handling of non-sealed radiopharmaceuticals poses significant risks of occupational exposure and radioactive contamination. With rapid growth in demand, an increasing number of workers are long-term exposed to various radiation hazards. However, the exposure characteristics and dosimetry basics remain poorly understood.

[METHODS] This study reconstructed 1189 personal dose equivalent data for 311 radiation workers from 2021 to 2023 in China to analyze exposure characteristics. Through on-site inspections of the radiation levels in 15 representative facilities, 1889 measurement points were assessed for radiation hazard distributions and dose contributions. Based on Biological Effects of Ionizing Radiation-VII (BEIR-VII) risk models, 120 exposure scenarios were considered to estimate excess lifetime risks of stochastic effects.

[RESULTS] The maximum annual effective dose reaches 5.29 mSv and presents a decreasing trend annually. Some occupational personnel, such as production technicians, should be given more attention regarding radiation exposure. Monitoring of nuclide operational quantities is conducive to avoiding overexposure. Gamma-rays are the largest dose source, contributing more than 75 % of the personal dose, with a maximum dose rate of 50 μSv/h. The dose contribution of neutrons cannot be ignored, particularly for cyclotron operators. The highest lifetime risks of thyroid cancer and leukemia caused by annual doses are 1.8 × 10 and 1.03 × 10, respectively. The radiological risk also increases with longer working years and higher doses.

[CONCLUSIONS] It is necessary to strengthen radiation protection for some workers, especially production technicians and cyclotron operators, and conduct radiation monitoring in high-risk workplaces, including hot cells. The radiological risks caused by accumulated dose should not be ignored, particularly during the early career.