By any reasonable standard of proof, the combination of human epidemiology and track-analysis demonstrates that there is no threshold dose or dose-rate below which "repair" invariably prevents health harm.
John GofmanMy estimate is that about 94,000 cancer fatalities for the future are being induced with each year of medical diagnostic X-rays (in US).
John GofmanIonizing radiation may well be the most important single cause of cancer, birth defects, and genetic disorders... The stakes for human health are very, very high in radiation matters. It is essential that people take no chance that conflict-of-interest is producing radiation databases which...cannot be trusted.
John Gofman