Radiation hazards in children - lessons from Chernobyl, Three Mile Island and Fukushima.

On March 11, 2011, Japan was hit by the Great East Japan Earthquake followed by the Fukushima Daiichi Nuclear Disaster. Firstly, this review focuses on what happened after the accidents at the Three Mile Island nuclear power station in 1979 and the Chernobyl nuclear power plant in 1986, in terms of the effects of these incidents on health. The most critical issue when considering the effects of radiation on the health of children was the increase of thyroid cancer, as clearly demonstrated among people who were children or adolescence at the time of the Chernobyl accident. Therefore, in the early days after a nuclear accident, the primary concern should be efforts to prevent the exposure of children to radioactive iodine through inhalation and ingestion, because radioactive iodine preferentially accumulates in the thyroid. In the longer term, another concern is exposure to radionuclides with long half-lives, including cesium137 and cesium134, with physical half-lives of 30 and 2 years, respectively. Secondly, fetal radiation risks and radiobiological studies on low-level radiation are briefly reviewed, with reference to the effects upon the developing brain. A fetal dose of 100 mSv may increase the risk of an effect on brain development, especially neuronal migration, based upon the results of experiments with rodents. Finally, this review proposes that research on the health effects of low level radiation should be prioritized so that accurate information on the effects of radiation can be disseminated and prevent the prevalence of unnecessary fear lacking scientific justification.