Effects of prenatal exposure to the Chernobyl radioiodine on postnatal physical development of children from the Kaluga region

The paper presents analysis of physical development of children exposed to Chernobyl 131I (radioiodine) in utero. The study cohort comprised 237 children, among them 125 boys and 112 girls, resided in the rayons of the Kaluga region affected by the Chernobyl accidents in 1986. The fetuses were exposed to radioiodine at different gestation stages; 102 embryos were exposed to radioiodine at the late gestation stage 29-40 weeks and during ~13 weeks in their postnatal life. Physical development was estimated by body mass/length ratio. Anthropometric measurements were made in the 1st, 5th and 10th years of life and compared with age- and sex-specific standards. Existence of abnormalities in physical development of children was determined by percentile method. In 49.5% of children observed in the first year after the exposure to radiodine and in 51.5% of children observed in the 5th year after the exposure different abnormal deviations in their physical development assessed by body mass/length ratio were found. In 9 years after the exposure abnormal physical development was found in 44.4% of children, however, the observed reduction was statistically insignificant. The incidence of the deviations found in the study cohort did not depend on sex and fetal age at exposure to radioiodine, current thyroid diseases with prevailed diffuse nontoxic goiter (91.0% of the total number of children with thyroid diseases). During the follow-up period ranking of abnormal deviations of physical development changed. With aging in the group of children with abnormal physical development the fraction of children with short and very short stature increased from 31.9% in 1 year after radioiodine exposure to 55.3% in 10 years later (p97 centiles) reduced from 31.9% in the 1st year of life to 9.2% in the 10th year (p function show_eabstract() { $('#eabstract1').hide(); $('#eabstract2').show(); $('#eabstract_expand').hide(); }