Retrospective Dosimetry in the Southern Urals: 30 Years of Studies Within the Framework of the Project 1.1

Imperfection of radioactive waste storage technologies in the initial period of Mayak Production Association operation in 1950s led to a long-term radioactive contamination of the vast territories of the Southern and Middle Urals in Russia. In 2024, it was 30 years since the beginning of the collaborative studies of Russian and American scientists in the framework of the Project 1.1 performed under the aegis of the Joint Coordinating Committee for Radiation Effects Research. A number of science and technology tasks arise while assessing the individual exposure doses for the members of epidemiological cohorts, viz. Techa River Cohort, EURT Cohort, Cohort of the Exposed Population Offspring, and Cohort of Southern Urals Population Exposed to Radiation (SUPER cohort), the latter being established in recent years. These tasks have been accomplished owing to the collaboration. The paper describes the main tasks and methodology of dosimetric studies in the Southern Urals as well as the most prominent scientific achievements. For instance, development of the dosimetry system to calculate exposure doses for people of different sex and age based on the radionuclide measurement results in human organs and tissues. The participants of the Project 1.1 have received an invaluable experience of conducting joint scientific research. The obtained estimates of the radiogenic risk will ultimately be used in the provision of radiation safety of the population around the globe.