Is eye lens dosimetry needed in nuclear medicine?

Area of Science:

• Nuclear Medicine
• Radiation Protection
• Occupational Health

Background:

• Nuclear medicine personnel face variable radiation exposure based on radioactive isotopes and procedures.
• The individual dose limit for the eye lens has significantly decreased from 150 mSv yr⁻¹ to 20 mSv yr⁻¹.
• This reduction necessitates a re-evaluation of routine eye lens dosimetry for radiation protection.

Purpose of the Study:

• To analyze eye lens exposure in nuclear medicine and radiopharmaceutical production personnel.
• To assess the advisability of routine eye lens exposure monitoring in light of new dose limits.
• To identify specific roles where monitoring is most critical.

Main Methods:

• Analysis of exposure data for personnel handling common diagnostic (99mTc, 18F) and therapeutic (131I) radionuclides.
• Utilized thermoluminescent detectors for dose measurements.
• Evaluated exposure against the revised annual dose limit of 20 mSv yr⁻¹.

Main Results:

• Identified scenarios where the annual personal dose equivalent, Hp(3), can exceed three times the new limit (20 mSv yr⁻¹).
• Exposure levels vary significantly based on the specific radionuclide and manual procedures involved.

Conclusions:

• Routine Hp(3) dose monitoring is recommended for radiopharmacists involved in 99mTc labeling.
• Routine monitoring is also advised for chemists in 18F-FDG quality control departments performing manual tasks.
• These recommendations aim to ensure compliance with updated radiation protection standards for the eye lens.