[Hiroshima/Nagasaki survivors and their offspring: results of longterm epidemiological studies]

After the atomic bombing of Hiroshima and Nagasaki, long-term epidemiological studies were undertaken on the irradiated survivors and their offspring, and are still underway. These thorough studies involving tens of thousands of persons and published in hundreds of papers have shown a moderate increase in cancer incidence for irradiated survivors, with limited impact on their life span (loss of one year at most). In studies on the offspring of these survivors, no statistically significant deleterious effect on malformation frequency, incidence of mutations or mortality from cancer and other diseases has been seen so far. These data are actually the basis for current radiation safety levels; they show that health risks from radiation are limited, but they are not applicable to complex situations such as nuclear power station accidents that involve diverse types of radiation as well as contamination by radioactive materials.