The paper presents the key milestones and outcomes of 65-year studies of the carcinogenic consequences of accidental radiation exposure of the population of the Ural region. The radioactive contamination of the Techa River and the 1957 accident at the Mayak Production Association were the reasons of the long-term population exposure at a wide dose-range. The most important tasks of the study were the reconstruction of individual doses, follow-up of the solid cancer and leukemia incidence and mortality among cohort members. The research results have shown that chronic human exposure, in comparison to acute exposure, does not reduce the risk of developing malignant tumors and leukemias. The value of the dose-rate factor does not exceed "one".
Thus, according to our data, the Publication 103 of the International Commission on Radiological Protection underestimates the radiation risk of malignant tumors and leukemias in case of low dose-rate exposure of the population by a factor of two. Prospects for further radio-epidemiological studies in the Urals are associated with the analysis of the cohort of Southern Urals Populations Exposed to Radiation, which includes about 63 thousand exposed people and makes it possible to assess the radiation risk of solid cancers of certain localizations, certain types of leukemia, and non-cancer effects.