[Monitoring of I-125 contamination in vivo by analysis of the saliva].

Monitoring of workers who did iodination of protein was performed for 5 months on 10 persons. The activity in saliva was evaluated following the sun peak method by using a NaI(Tl) detector and a 400-channel analyzer. The concentration of 125I in saliva ranged 4.65 +/- 2.1 cBq (1.26 +/- 0.57 pCi)/ml to 135 +/- 2.7 cBq (36.45 +/- 0.73 pCi)/ml and the average was 20.8 +/- 1.9 cBq (5.62 +/- 0.51 pCi)/ml. The ratio of concentration in saliva to used activity ranged (2.2 +/- 0.64) X 10(-9) to (3.6 +/- 0.073) X 10(-8) and the average was (8.1 +/- 1.1) X 10(-9). The thyroidal uptake per iodination ranged 146 Bq (3.94 nCi) to 2700 Bq (72.9 nCi). The ratio of the uptake to the used activity ranged from 7.3 X 10(-5) to 5.4 X 10(-6). The thyroidal absorbed dose ranged from 378 microGy (37.8 mrad) to 4740 microGy (474 mrad). Monitoring of 125I-in saliva was proved to be a useful method to investigate the internal contamination of workers doing iodination.