Physical heights of children with prolonged low dose-rate γ-radiation exposure in radiocontaminated buildings

Purpose: To evaluate low dose-rate radiation effects on the physical heights of children staying in apartments with ⁶⁰Co-contaminated steel construction. Materials and methods: Children who once resided in radiocontaminated apartments since early 1983 were examined for height and body weight status from age 1 month to 18 years and before they moved out of the apartments. The physical heights and body weights of 21 898 age- and sex-matched non-exposed children from a nationwide school surveillance in 1997-98 were taken as controls. The physical height data were shown as height percentiles (HP) compared with reference children and age-specific relative height differences (RHD). Results: HP and RHD in 48 exposed boys and 37 girls were analysed using generalized estimating equations (GEE), which accounted for multiple measurements and correlation between these measurements in the same individuals during this period. After adjusting for effects from parental heights and body mass index (BMI), clear dose-related decreases in HP and RHD were observed in the exposed boys with a cumulative exposure > 60 mSv. Conclusions: Prolonged low dose-rate γ-radiation exposure was associated with adverse effects on the physical heights of growing boys, but were less apparent in the exposed girls.