Occupational exposure to 131I-a case study.

In a laboratory in a company manufacturing radio-pharmaceuticals, a laboratory technician was contaminated with I-131. The employee was preparing I-131 capsules for thyroid carcinoma treatment. The employee was wearing two pairs of protective gloves and, when changing gloves, noticed a rupture in the right inner glove but no visible rupture in the outer glove. Only 3-4 h later, routine monitoring revealed heavy contamination of the back of the right hand. Immediate actions to decontaminate the hand were taken on-site. Stable iodine was not administered. On the next day, besides persisting heavy contamination of the hand, I-131 was also detected in the thyroid gland. Based on original measurements on-site and later follow-up at STUK, including surface contamination measurements and whole body counting, the original I-131 activity on the hand was estimated at 12 MBq and the superficial skin dose at 33 Gy, affecting a skin area of about 10 cm(2). The thyroid dose was estimated at 430 mGy. Eleven days after the incident, the skin was dry and slightly desquamated. After 15 d, the skin was intact with no desquamation left. No further signs of skin damage have occurred. Cytogenetic analysis of circulating lymphocytes indicated a slight elevation of chromosomal aberrations.