Excessive radiation exposure can lead to serious health problems on top of cancer, according to a report in Radiation Research, the journal of the Radiation Effects Research Foundation.
The study identified a small but "statistically significant" association between radiation dose and deaths from non-cancer diseases in 86,572 Japanese atomic bomb survivors.
The study found that non-cancer death rates increased with the radiation level received, although the mechanisms for such effects were unknown.
"There is a systematic increase in non-cancer death rates with radiation dose, and for heavily exposed survivors, rates are about 10 per cent above normal levels," the study suggests.
The foundation is a private, non-profit body funded by the Japanese government and the US government via the National Academy of Sciences.