The recent incidence of leukemia in Hiroshima atomic bomb survivors

On the recent trend of leukemia in atomic bomb survivors in Hiroshima City, the onset of leukemia in the survivors was outlined and the epidemiological survey for the incidence was described, which showed a fall in recent years. However, in comparison with the non-exposes cases, the rate is still high, indicating that the survivors are not yet clear from the risk of the onset of leukemia due to exposure. The incidence of survivors exposed at high age continues to be high, and they have chromosome aberration. Those exposed in youth showed a marked fall recently but still require a long-term, deliberate observation. (Kanao, N.)