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Radiation Protection Dosimetry 68:97-103 (1996)
© 1996 Oxford University Press
Epidemiological Evidence of Hazard
Epidemiological evidence of the long-term effects of exposure to radionuclides is limited to the production of cancer. For most radionuclides of medical or social interest the numbers of people exposed have been too few or the doses have been too small for the observed risks to have statistical stability. Useful data are available only for thorium (from the use of Thorotrast), radium (from the medicinal use of 224Ra), radon (from the occupational exposure of 11 groups of miners) and radioiodine (from its use in the treatment of thyroid cancers and thyrotoxicosis and its release in nuclear accidents). The findings suggest that prediction from the knowledge of the effects of moderate doses of low LET radiation with current assumptions about the radiation weighting factor for alpha radiation and the reduction in risk with low dose rates is not far out, although in some instances the weighting factor may be too high or the dose rate reduction factor too low.