Iodine-125 induced micronuclei and sperm head abnormalities in mice

Swiss albino mice were injected with 0 (controls) 5, 10 or 15 microCi of iodine-125 (125I) and a high incidence of micronuclei in young bone marrow erythrocytes and of sperm head abnormalities was observed. The percentage of polychromatic erythrocytes containing micronuclei in mice treated with 0, 2.5, 5 and 7.5 microCi of 125I administered twice (at 30 and 6 h before sampling) was 0.23, 0.44, 0.56 and 0.72, respectively. The percentage (mean) of abnormal sperm recorded in controls during 1-3, 4-5 and 6-8 weeks was 3.3, 3.7 and 3.7 respectively, whereas the values for the same periods in the 5 microCi (5.5, 6.4 and 7.3), 10 microCi (7.7, 8.4 and 10.0) and 15 microCi (10.3, 9.9 and 10.2) groups were significantly higher. These results suggest that 125I can induce genetic damage in both somatic and germ cells.