Preconceptional occupational exposure to mothers: endocrine pathology in the offspring

Effects of preconceptional (before conception) maternal exposure are understudied for the purpose of radiological protection of female personnel contacting with radiation. Aim of the study is the analysis of endocrinopathy among the children of female workers from the Mayak Production Association (PA), the firstborn of the nuclear industry, exposed to long-term preconceptional radiation effect. The retrospective analysis was carried out among the child population of the Closed Administrative Ter-ritorial Unit (CATU) Ozersk, and was based on the analysis of 10,581 medical histories (the main group consists of 1,742 children of Mayak PA female workers exposed to external gamma radiation in the preconceptional period; the comparison group – 8,839 children of unexposed parents). The groups are comparable based on the fact of birth and residence in CATU, the period of children’s birth (1949-1973), the follow-up until the age of 15, the unified medical care in CATU. First registered before the age of 15 endocrinopathies were analyzed. The incidence structure and rate were presented, the standardized incidence ratio (SIR) with 95% confidence interval was calculated taking into account accumulated preconceptional doses of external gamma exposure to the ovaries. Significant excess of the endocrine pathology level (35.4 vs 30.8 per 103 of person-years; X2=35.5, p<0.0001) was registered in the main group, and in particular non-tumor pathology of the thyroid gland especially among the girls. The SIR calculation demonstrated significant excess of endo-crinopathies among the offspring of exposed mothers in whole – SIR 1.21 (1.12-1.3) and when distributed by gender. Non-tumor thyreopathology was registered significantly more often among the offspring of exposed mothers: in the group as a whole – 1.89 (1.54-2.28), among the boys – 1.61 (1.14-2.2), among the girls – 2.12 (1.64-2.69). An extensive range of total doses of external gamma radiation to the ovaries was observed. The dose categories of preconceptional maternal ex-posure corresponding to statistically significant excess of the level of endocrinopathies in the off-spring, were indicated. Diseases of the endocrine system and, in particular, thyroid pathology were diagnosed significantly more often among children of Mayak PA female employees who were exposed to external gamma radiation before conception than among children in the comparison group.