Evaluation of exposure characteristics and radiological risks for cyclotron-based ¹⁸F radiopharmaceutical production...

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.

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.

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^-5 and 1.03 × 10^-5, respectively. The radiological risk also increases with longer working years and higher doses.

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.