Thyroid-stimulating hormone levels in children from Chernobyl

This study assesses parameters of thyroid function in persons who resided in Ukraine, Belarus, and southern Russia and exposed at 0 to 16 years of age to radioiodine contamination from the Chernobyl accident. Six to eight years after the accident a group of 300 young people who had immigrated to Israel were interviewed, underwent physical and ultrasound thyroid examination, and had their serum tested for thyroid-stimulating hormones (TSH), thyroid hormones, thyroglobulin, and antithyroid antibodies. Comparative groups came from areas with high (> 1 Ci/km²) or low (< 1 Ci/km²) ¹³⁷Cs ground contamination. Girls from high contamination areas, when compared to girls from areas with low ground contamination, showed significant upward shifts in levels of serum TSH (p = 0.023) although remaining within normal limits. Boys showed no significant differences. There was no evidence for differences in thyroid size or nodularity between the two groups of girls. A working hypothesis is proposed by which the shift in TSH levels in girls from high radiocontamination areas was associated with subclinical radiation damage from environmental radioiodine at the time of the accident.