Number of MN, 6 days after irradiation for groups I to III, per 1000 BN cells for each value of dose, i.e., 5, 10, 50 and 100, mGy. In group I irradiated cells were cultured with fresh medium after exposure to the aforementioned radiation doses. In group II, non-irradiated cells received irradiated medium. Finally, group III corresponds to irradiated cells cultured after centrifugation with supplemented fresh medium. The non-irradiated cell cultures are marked as 0 mGy. Data represent means of 3 independent experiments, ± SEM. In all groups, radiation significantly increased the number of MN when compared with its own controls (p<0.05), with exception in group III for 5 mGy where the increasing of MN was almost the same (p=0.68). Similarly to earlier effects, the trend to reach a plateau after 10 mGy for group II is observed. Note: the lines are purely eye guided.