Risk of central nervous system tumors in the offspring of individuals exposed to production radiation

Aim. To assess the risk of malignant central nervous system (CNS) tumors among the first-generation offspring of workers from the Mayak Production Association. Materials and Methods . A retrospective epidemiological analysis was conducted in a cohort of the offspring of workers from Russia's first nuclear power plant (n = 8890), born between 1949 and 1973. The comparison group consisted of 4345 offspring born during the same period to non-exposed parents. The observation period covered 72 years (1949−2020), with a total of 818,208 person-years of follow-up. The analysis focused on the frequency, dynamics, and structure of CNS malignancies. The relative risk of CNS tumors and the excess relative risk per unit dose of parental occupational radiation exposure were calculated with 95% confidence intervals. Results . Overall, the frequency of CNS tumors in both groups over the entire observation period did not differ significantly (3.4 per 1000 in the main group, 1.8 per 1000 in the comparison group). Analysis of CNS tumor incidence dynamics across calendar periods showed no significant differences, with the peak in the main group occurring during 2001−2010. No significant differences were found in the age of CNS tumor onset or the average age of parents at the time of offspring birth. Histological structure and localization of CNS tumors varied across groups. The relative risk assessment for CNS tumors showed a statistically insignificant increase in risk among the offspring in the main group when considering total observations and sex-specific analyses. Among the offspring of mothers with confirmed preconceptional and intrauterine occupational radiation exposure, the relative risk of CNS tumors was higher for males and both sexes combined (3.6 [1.06−12.28] and 2.74 [1.08−6.93]; 4.34 [1.27−14.77] and 3.3 [1.31−8.36], respectively). However, the analysis of excess relative risk did not indicate significant risk estimates for maternal radiation exposure, neither in general nor across different dose intervals. Conclusion . The study did not confirm the hypothesis that parental occupational radiation exposure influences the risk of CNS tumors in offspring. Given the relatively young age of the cohort and the low number of CNS tumor cases, issues related to maternal radiation exposure require further observation.