By the way, Ikegami also said that tests with tritium failed to show biological damage. They exposed various species to much higher concentrations than the safety rules allow for people, but the plants and fish seemed fine.
Mike Melich says the radiation standards were more or less pulled out of a hat at the beginning of the nuclear power era. Actual tests with animals show a wide range of responses to a given dose. On the other hand, there is no doubt that radiation causes harm, especially to children. It is difficult to know what a safe dose might be. It is also clear that many areas around Fukushima are heavily contaminated and will be for decades to come. The distribution of radioactive debris is shown in neat color coded bands on maps, but in real life it is not uniform. - Jed
