Occupational exposure of the parents: general mortality among the offspring

Abstract

Epidemiological studies describing the effects of parental radiation exposure on the health of children are highly contradictory. Aim of the study was to analyze the general mortality of offspring whose parents were exposed to occupational radiation at Mayak, the first nuclear power plant in Russia. Material and methods. A retrospective analysis was conducted in a cohort of 19 999 offspring born in 1949–1973, of which 12 836 were born in families of Mayak workers and 7163 were born from non-irradiated parents. General mortality was analyzed taking into account sex, calendar period, nosologies, and doses of external gamma irradiation of the gonads before conception. The standardized mortality ratio (SMR) was calculated in comparison with the national standard, the relative risk (RRisk) was estimated taking into account disease classes and the excess relative risk (ERRisk) with a 95 % confidence interval taking into account the doses of external gamma irradiation of the gonads. Results and discussion. In the main group, 2758 deaths have been registered for the period 1949–2020 (214.9 per 103), which is significantly less than in the comparison group (1689 cases, 235.8 per 103) (p = 0.0006). The most frequently observed diseases were “Injuries and poisoning”, “Diseases of the circulatory system” and “Malignant neoplasms” without significant differences between the groups. The risk of infectious pathology, “Certain conditions of the perinatal period” and “Respiratory diseases” in the comparison group was significantly higher than in the main group. Overall, the RRisk of death was higher in the comparison group for female offspring – 0.78 (0.69–0.88) and for both sexes – 0.89 (0.83–0.95). In many categories of parental age, there was a clear predominance of mortality in the comparison group. The SMR analysis showed that the general mortality from all causes among female offspring in the main group and among male offspring in both groups was statistically significantly lower than in the Russian Federation. The calculation of the ERRisk did not reveal an excess of risk coefficients either overall or in different dose categories. Conclusion. The study results did not indicate an increased risk of death among the offspring of individuals exposed to occupational radiation. Taking into consideration the relatively young age of the observed cohort, further epidemiological monitoring is required.

Keywords

• radiation
• external gamma irradiation
• mayak
• descendants of irradiated persons
• general mortality