Assessment of extremity exposure to technologists working manually with99mTc-labelled radiopharmaceuticals and with an automatic injection system for18F-FDG

Abstract

The hands of nuclear medicine (NM) personnel involved in radiopharmaceutical preparation and administration can receive significant radiation doses. The dose distribution across the hand is nonuniform and the Hp(0.07) doses obtained by an individual passive ring dosimeter do not always present a real situation. The aim of this study was to assess the extremity exposure of NM workers working with^99mTc-labelled radiopharmaceuticals and with an automatic IRIDE (COMECER, Italy)¹⁸F-FDG injection system. Hp(0.07) doses were measured using calibrated thermoluminescent dosimeters-100 (TLD-100) and were read by a RIALTO TLD (NE Technology) reader. It was found that the most exposed parts of the hand during work with¹⁸F and^99mTc radionuclides are the fingertips of the thumb, index finger and middle finger. The maximum fingertip doses were 1.3-2.4 times higher compared with the doses from the typical monitoring position (base of the middle finger of the dominant hand). When working with^99mTc, the average hand doses were relatively high, i.e. 0.17 ± 0.04 and 0.37 ± 0.13 mSv Gbq^-1for the left and the right hand, respectively, during preparation, and 58 ± 20 and 53 ± 13µSv GBq^-1for the left and the right hand, respectively, during administration of^99mTc labelled radiopharmaceuticals. Meanwhile, the lowest doses were found for hands during administration of¹⁸F-FDG (average hand dose 28 ± 13µSv GBq^-1for the left hand and 28 ± 7µSv GBq^-1for the right hand), which shows the advantages of automated injection/infusion systems, thus implementation of automatic infusion/injection in hospitals could be an expedient way to optimize Hp(0.07) doses to NM workers.

Keywords: extremity occupational exposure; nuclear medicine; radiation risk; thermoluminescence dosimeters.