In Utero Exposure to Chernobyl Fallout in Belarus and Ukraine
DCEG investigators in the Radiation Epidemiology Branch (REB) coordinated a study of health effects in persons exposed to Chernobyl fallout in utero and early life in Belarus (2,964 subjects) and in Ukraine (2,582 subjects). They applied comprehensive efforts to develop a complex dosimetry system for these cohort studies, recontructing the following individual doses for each cohort member:
- Doses to the fetus's thyroid gland from intake of 131I by mothers; and
- Postnatal (if applicable) dose to the thyroid gland from intake of 131I by the infant from breast milk and other foodstuffs.
In addition, in Belarus, investigators reconstructed thyroid and whole-body doses due to prenatal and postnatal external irradiation from gamma-emitting radionuclides deposited on the ground, and prenatal and postnatal intake of long-lived cesium isotopes (134Cs and 137Cs). The estimates of in utero thyroid doses from 131I intakes were derived from the model recommended by the International Commission on Radiological Protection (ICRP) Publication 88 with account to maternal direct thyroid gland measurements of 131I activity, if available. Mean in utero thyroid doses for cohort members from intakes of 131I by the mothers were estimated to be 106 mGy in Belarus (preliminary) and 72 mGy in Ukraine (Likhtarov et al. 2011). Special efforts are underway to evaluate uncertainty in reconstructed questionnaire-based doses due possibly to poor memory recall of mother during dosimetry interview (Drozdovitch et al. 2016).
Drozdovitch V, Kukhta T, Minenko V, Trofimik S, Bouville A, Potischman N. Reliability of questionnaire data in the distant past: Relevance for radiation exposure assessment. Article abstract Health Phys 2016 110(1):74-92.
Likhtarov I., Kovgan L., Chepurny M., Ivanova O., Boyko Z., Ratia G., Masiuk S., Gerasymenko V., Drozdovitch V., Berkovski V., Hatch M., Brenner A., Luckyanov N., Voillequé P., Bouville A. Estimation of the thyroid doses for Ukrainian children exposed in utero after the Chernobyl accident. Article abstract Health Phys 2011; 100(6):583-593