Estimation of airborne contamination during therapeutic radioiodine-131(I-131) administration: A comparative study...

Radioiodine-131(I-131) is widely used in the treatment of thyroid diseases. Despite its therapeutic advantages, working with unsealed sources such as I-131poses risk of airborne contamination and occupational radiation exposure, especially from airborne contamination during the preparation and administration procedures.

This study aims to compare the airborne contamination levels during the administration of I-131in capsule and solution forms by estimating the Derived Air Concentration (DAC) during therapeutic procedures and evaluating occupational exposure risk.

Airborne contamination was measured by using a portable air sampler is equipped with charcoal-impregnated cellulose filters during the dispensing and administration of therapeutic doses (range 50-200 mCi) of I-131.The collected samples were analysed by using a well counter based dose calibrator and a SPECT-CT machine. The DAC values were calculated and compared to the International radiation safety regulatory agencies like IAEA, ICRP prescribed limits.

A total of 104 administrations were analysed over a period of 13months. Airborne contamination levels were significantly lower during the use of I-131capsules compared to solution form. Minimum airborne activity was 8.53Bq/m³ (50 mCi of I-131 in capsule form), whereas a maximum contamination of 76.50 Bq/m³ (200 mCi of I-131solution). All measured concentrations remained below DAC limit of 416.7 Bq/m³ (P < 0.01).

I-131capsules significantly reduce airborne contamination and occupational exposure risks compared to solution form. The use of capsule-based therapies ensures good compliance with radiation safety standards (ICRP and IAEA recommendations).