Extremity Exposure with ^99mTc - Labelled Radiopharmaceuticals in Diagnostic Nuclear Medicine

Background: Extremity exposures may raise the risk of cancer induction among radiographers involved in the preparation and administration of technetium-99m labelled radiopharmaceuticals. Objective: To estimate finger doses on radiographers at a South African tertiary hospital. Methods: Adhesive tape was used to securely fix a calibrated thermoluminescent dosimeter (TLD) on fingertips and bases of ring and index fingers of both hands of five radiographers who prepared and administered technetium-99m labelled radiopharmaceuticals. Rubber gloves were worn to avoid TLD contamination. TLDs doses were read with a Harsaw TLD Reader (Model 3500) after a week. Results: Five radiographers prepared and administered technitium-99m labelled radiopharmaceuticals (activity range; 78.20 GBq - 132.78 GBq during a one-week measurement period). A radiographer handling 132.78 GBq received 4.74±0.52 mSv on both hands; 5.52, 4.55, 5.11 and 4.60 mSv on the fingertip of the index finger of the dominant hand (FIDH), fingertip of the ring finger of the dominant hand (FRDH), fingertip of the index finger of the non-dominant hand (FINDH) and fingertip of the ring finger of the non-dominant hand (FRNDH), respectively. The respective doses received on the finger bases were 4.50 mSv, 4.60, 4.21 and 3.48 mSv. The radiographer handling 78.20 GBq received 0.85±0.18 mSv on both hands, 1.04, 1.17, 0.77 and 1 mSv for the FIDH, FRDH, FINDH and FRNDH, respectively, while respective doses for the bases were 0.8, 0.9, 0.6 and 0.8 mSv. Conclusion: The extremity exposures were below the annual limit (500 mSv). However, the use of syringe shields could still reduce the finger doses further.