The risk of oncohematological pathology in children of workers employed at radiation hazardous production

Abstract

Preconceptive irradiation is considered to be a potential risk factor that can cause hemolymphoblastosis in children con-ceived and borne by irradiated parents. A population cohort that comprises workers employed at "Mayak" Production Association (Mayak PA), the first nuclear cycle enterprise, is a unique sampling to calculate a carcinogenic risk in their children. Our research goal was to assess risk of hemolymphoblastosis among children conceived and borne by workers employed at Mayak PA with individual preconceptive accumulated absorbed dozes. Data and methods. We performed retrospective research as per "case-control" study among all the people living in the city of Ozersk located near Mayak PA. Hemolymphoblastosis diagnosed in people younger than 25 in 1949–2009 (81 people) were considered to be "cases"; "controls were chosen taking into account sex, birth date, and parents' age when a child was borne (324 people). We calculated odds ratio and excessive relative risk per external gamma-radiation dose unit (ERR/Gy) with 95 % confidence interval; to do that, we applied PEGAN program module of EPICURE software. Results. Acute leukemia prevailed in the structure of hemolymphoblastosis, acute lymphatic leukemia occupying the first place. We didn't reveal any statistic correlation between a factor related to parents' preconceptive irradiation and oncohema-tologic pathologies in their offspring: overall, odds relation was equal to 0.76 (0.46–1.26). As we analyzed "dose – effect" cor-relation, we didn't reveal any statistically significant increase in morbidity with hemolymphoblastosis depending on a dose of irradiation accumulated by their parents. ERR/Gy quotients were insignificant both for a dose accumulated by a mother and that accumulated by a father. Non-parametric analysis taking into account dose categories didn't reveal any elevated risks either. Conclusion. We didn't detect any dose dependence between long-term preconceptive external gamma-irradiation accumulated by parents and risks of hemolymphoblastosis in their children. However, a relatively insignificant number of hemolymphoblastosis cases among children younger than 25 imposes certain limitations on validity of our conclusions. Susceptibility to neoplasms in children and manifestation of the effect as a solid carcinoma at older ages are rather probable and it means that further observation and research is required.

Keywords

• preconceptive radiation exposure of workers
• children
• dose dependence
• risk assessment
• malignant neoplasms in lymphoid and blood-making tissues