Abstract: Aim: was to analyze the risk of malignancy incidence as a result of exposure of small doses of diagnostic radiation when examining patients on computed tomography (CT). Material and methods: a retrospective study was conducted on the base of analysis of information from archival protocols for examinations of patients living in Ozersk city and examined in computed tomography department of the Chelyabinsk Regional Clinical Hospital for the period 1993-2004. Study includes generalized material containing data from several population registers of the Laboratory of Radiation Epidemiology of the South Ural Institute of Biophysics. Results: study revealed the presence of a statistically insignificant excess of the risk of incidence of malignancy among patients who underwent a CT study from the beginning of the appearance of this type of study in hospitals in the Chelyabinsk region until the end of the first stage of epidemiological surveillance - December 31, 2004. Conclusion: obtained results are interesting for various categories of specialists: radiologists, radiation epidemiologists, radiobiologists and radiation hygiene specialists. Further research is needed with an extension of the retrospective observation period. References 1. Collection of legislation of the Russian Federation. Federal Law 21.11.2011 No. 323-FZ «On Principles of the Protection of Citizens' Health in the Russian Federation». Part 4, article 34 [In Russ]. https://www.rosminzdrav.ru/documents/7025 1. Narkevich BYa, Dolgushin BI. Radiation safety assurance in computed tomography and interventional radiology. REJR. 2013; 2 (3): 7–19. 2. Brenner DJ, Hall EJ. Computed tomography – an increasing source of radiation exposure. N Engl J Med 2007; 357: 2277-2284. 3. Order of the Ministry of Health of the Russian Federation No. 298 of July 31, 2000, dated January 9, 1996, No. 3-FZ (Federal Law) «On Approval of the Regulation on the Unified State System of Control and Accounting for iIndividual Exposures of Citizens» [In Russ]. http://legalacts.ru/doc/prikaz-minzdrava-rf-ot-31072000-n-298/ 4. Decree of the Government of the Russian Federation dated 16.06.97 No. 718 «On the procedure for creating a unified state system for monitoring and recording individual doses to citizens» [In Russ]. http://legalacts.ru/doc/postanovlenie-pravitelstva-rf-ot-16061997-n-718/ 5. Koshurnikova NA, Kabirova NR, Bolotnikova MG, et al. Description of the register of persons, had lived in childhood near the Mayak Production Association. Medical Radiology and Radiation Safety. 2003; 2: 27-34 [In Russ]. 6. Koshurnikova NA, Shilnikova NS, Okatenko PV, et al. Characteristics of cohort of workers of «Mayak» PO. Medical radiology and radiation safety. 1998; 43 (6): 43–57 [In Russ]. 7. United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and effects of ionizing radiation: United Nations Scientific Committee on the Effects of Atomic Radiation: UNSCEAR 2012 report to the General Assembly. Scientific Annexes. New York. United Nations; 2015. 8. Abramson, JH. WINPEPI updated: computer programs for epidemiologists, and their teaching potential. Epidemiologic Perspectives & Innovations. 2011; 8:1 10. Preston DL. Epicure User’s Guide. USA: 330. 11. Howe GR. Lung Cancer Mortality between 1950 and 1987 after Exposure to Fractionated Moderate-Dose-Rate Ionizing Radiation in the Canadian Fluoroscopy Cohort Study and the Comparison with Lung Cancer Mortality in the Atomic Bomb Survivors Study. Radiation Research. 1995; 142: 295-304. 12. Ivanov VK, Kashcheev VV, Menyaylo SYu, et al. Radiation risk of medical exposure. Radiation and risk. 2012; 21 (4): 7-23 [In Russ]. 13. Pearce MS, Salotti JA, Little MP, et al. Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumors: a retrospective cohort study. The Lancet. 2012; 380. 14. Shilnikova NS, Preston DL, Ron E, et al. Cancer Mortality Risk among Workers at the Mayak Nuclear Complex. Radiation Research. 2003; 159: 787–798. 15. Lebedev NI, Osipov MV, Babintseva NA, et al. Register of patients undergoing CT scan - examinations in the department of radiation diagnostics of the Central Medical Center-71, Ozersk. REJR. 2017; 7 (2): 110-116 [In Russ]. https://doi.org/10.21569/2222-7415-2017-7-2-110-116 16. Finashov LV, Kuznetsova IS, Sokolnikov ME. Prostate cancer incidence among workers with work-related exposure of radiation at the Mayak Production Association. Radiation and Risk, 2019; 28 (4): 54–64 [In Russ]. https://doi.org/10.21870/0131-3878-2019-28-4-54-64 17. Fomin EP, Osipov MV. Pooled database of Ozyorsk population exposed to computed tomography. REJR 2019; 9 (2):234-239.
