Beta and electron dose calculations to skin due to contamination by common nuclear medicine radionuclides.

We present dose calculations to the basal cell layer of the epidermis resulting from skin contamination by radionuclides used in nuclear medicine. Dose calculations were made using the computer code VARSKIN, as modified by us to include these radionuclides and to account for their monoenergetic electron emissions. Results indicate that basal skin doses (taken to be at a depth of 0.007 cm) are approximately 1 cGy h-1 per 3.7 X 10(-4) Bq cm-2 (1 rad h-1 per muCi cm-2) from 99mTc, 111In and 201Tl, implying that established limits may be approached under certain circumstances. The implication of these results for small areas of contamination is also discussed.