Skin Uptake of 131I in a Veterinary Practice

Area of Science:

• Nuclear Medicine
• Radiation Safety
• Occupational Health

Background:

• Accidental radioactive contamination poses risks in healthcare settings.
• Veterinary nuclear medicine involves handling radioisotopes like Iodine-131 (131I).
• Accurate dose assessment is crucial for occupational health and safety.

Purpose of the Study:

• To quantify the dose from accidental trace 131I skin contamination.
• To establish a technician-specific effective half-life for 131I.
• To compare different methods for calculating thyroid committed dose equivalent (CDE).

Main Methods:

• In-vivo thyroid measurements to quantify 131I uptake and effective half-life.
• Ruled out inhalation and ingestion based on 131I's chemical properties.
• Calculated committed dose equivalent (CDE) using three distinct methods.

Main Results:

• Quantified 131I uptake at 2.2 kBq (60.1 nCi) with an effective half-life of 7.61 days.
• Assigned highest CDE to the thyroid as 4.1 mSv and shallow dose equivalent (SDE) as 0.22 mSv.
• Average CDE across three methods was 3.68 ± 0.38 mSv, showing a 10% coefficient of variation.

Conclusions:

• Trace amounts of radioiodine on intact skin can result in significant occupational radiation doses.
• Multiple dose calculation methods provide consistent results, ensuring accurate dose assessment.
• Establishing technician-specific effective half-lives enhances dose determination accuracy.