Iodine 131 (I-131), the principal component of nuclear fallout from the Chernobyl accident, concentrates in the thyroid gland and may pose risks to fetal development. To evaluate this, neonatal outcomes following the accident in April of 1986 were investigated in a cohort of 2582 in utero-exposed individuals from northern Ukraine for whom estimates of fetal thyroid I-131 dose were available. We carried out a retrospective review of cohort members' prenatal, delivery and newborn records. The relationships of dose with neonatal anthropometrics and gestational length were modeled via linear regression with adjustment for potentially confounding variables. We found similar, statistically significant dose-dependent reductions in both head circumference (-1.0 cm/Gy, P = 0.005) and chest circumference (-0.9 cm/Gy, P = 0.023), as well as a similar but non-significant reduction in neonatal length (-0.6 cm/Gy, P = 0.169). Gestational length was significantly increased with increasing fetal dose (0.5 wks/Gy, P = 0.007). There was no significant (P > 0.1) effect of fetal dose on birth weight. The observed associations of radioiodine exposure with decreased head and chest circumference are consistent with those observed in the Japanese in utero-exposed atomic bomb survivors.
Our data partly show a severe form of hypoparathyroidism of very young persons in the Chernobyl region, a finding which strongly supports the need of exact diagnosis and interdisciplinary treatment options of this postoperative disorder.
The aim of the present study was to develop atransplantation technique for restoration of thyroidfunction in rats with radioiodine-inducedhypothyroidism. Each Wistar rat received the dose of75.0 muCi of 131-iodine by intraperitonealinjection. The serum thyroxine and triiodothyroninevalues in all rats fell to low levels by 2.5 weeksafter radioiodine administration. Thexenotransplantation of 3-day-old newborn pig thyroidorgan culture was performed on day 18 afterradioactive ablation by injection into the fat tissueof anterior abdominal wall. Epithelial cell swarmswith follicular formation manifested themselves amongadipose tissue on day 7 as well as day 17 afterxenotransplantation. The serum thyroxine andtriiodothyronine values in the rats were generallywithin the euthyroid range by day 7-17 afterxenotransplantation. The thyroid gland of ratsreverted to the norm in morphofunctional appearance.These results indicated that the xenografted newbornpig thyroid organ culture allowed a restoration of thyroid function in Wistar rats with post-radioiodine hypothyroidism.