Assessment of health effects and reliability of radiation thyroid doses for belarusian persons exposed in utero and during early life to Chernobyl fallout

This paper describes the current status and preliminary results of thyroid screening and a study on reliability of radiation doses for 2965 persons exposed in utero and early life to Chernobyl fallout in Belarus. By 15 November 2020, 1194 study subjects have been screened. Among them, single thyroid nodule was diagnosed in 163 persons (13,7% of the total) and multiple thyroid nodules in 95 persons (8,0% of the total): 180 (15,1%) persons who had nodules detected for the first time at the screening and 78 (6,5%) persons who had nodules that had been detected previously (pre-screening thyroid nodules). Fifty-six out of 258 subjects (21,7%) with thyroid nodule were referred to Fine Needle Aspiration Biopsy (FNA), and among them 33 (58,9%) were biopsied. One person had surgery for thyroid cancer. In addition, five subjects had thyroid cancer diagnosed prior to screening. Information from 724 pairs of questionnaires obtained during the first and second personal interviews of 724 mothers were used to evaluate the reliability of radiation doses for the cohort members. A moderate degree of agreement was observed (Spearman's correlation coefficient rs=0,64, pWilcoxon=0,039) for total ecological doses calculated using data from the two interviews, while instrumental doses yielded an almost perfect agreement (rs=0,98, pWilcoxon=0,183). It was found that consistency of answers between two personal interviews is better among mothers of the Belarusian in utero cohort members than among mothers of the members of Belarusian-American cohort of individuals exposed in childhood and adolescence.

in utero cohort, thyroid, screening, radiation, 131I

1. Solid cancer incidence in atomic bomb survivors exposed in utero or as young children / D. Preston [et al.] // J Natl Cancer Inst. - 2008. - Vol. 100. - P. 428-436.

2. Cancer mortality among atomic bomb survivors exposed in utero or as young children / R. Delongchamp [et al.] // October 1950-May 1992. Radiat Res. - 1997. - Vol. 147. - P. 385-395.

3. Malignant disease in childhood and diagnostic irradiation in utero / A. Stewart [et al.] // Lancet. - 1956. - Vol. 268. - P. 447.

4. Risk of childhood cancer from fetal irradiation / R. Doll [et al.] // Br J Radiol. - 1997. - Vol. 70. - P. 130-139.

5. Incidence and mortality of solid cancers in people exposed in utero to ionizing radiation: Pooled analyses of two cohorts from the Southern Urals, Russia / A. Akleyev [et al.] // PLoS One. - 2006. - 11(8). - e0160372.

6. In utero exposure to radiation and haematological malignancies: pooled analysis of Southern Urals cohorts /j. Schüz [et al.] // Br J Cancer. - 2017. - Vol. 116. - P. 126-133.

7. Cancer mortality following in utero exposure among offspring of female Mayak Worker Cohort members / S. Schonfeld [et al.] // Radiat Res. - 2012. - Vol. 178. - P. 160-165.

8. A screening study of thyroid cancer and other thyroid diseases among individuals exposed in utero to iodine-131 from Chernobyl fallout / M. Hatch [et al.] // J Clin Endocrinol Metab. - 2009. - Vol. 94. - P. 899-906.

9. Thyroid cancer and benign nodules after in utero exposure to fallout from Chernobyl / M.Hatch [et al.] // J Clin Endocrinol Metab. - 2019. - Vol. 104. - P. 41-48.

10. Belarusian in utero cohort: new opportunity to evaluate health effects of prenatal and early-life exposure to ionizing radiation / V. Yauseyenka [et al.] // J Radiol Prot. - 2020. - Vol. 40. - P. 280-295.

11. A cohort study of thyroid cancer and other thyroid diseases following the Chornobyl accident: objectives, design, and methods / V. Stezhko [et al.] // Radiat Res. - 2004. - Vol. 161. - P. 481-492.

12. Формирование когорты лиц, облученных внутриутробно в Беларуси после аварии на Чернобыльской АЭС / В.В. Евсеенко [и др.] // Медико-биологические проблемы жизнедеятельности - 2016. - №1(15). - С.106-133.

13. International Commission on Radiological Protection. Doses to the embryo and fetus from intakes of radionuclides by the mother. ICRP Publication 88. Ann. ICRP. - 2001. - Vol. 31.

14. Reliability of questionnaire data in the distant past: relevance for radiation exposure assessment / V. Drozdovitch [et al.] // Health Phys. - 2016. - Vol. 110. - P. 74-92.

15. Thyroid dose estimates for a cohort of Belarusian persons exposed in utero and during early life to Chernobyl fallout / V. Drozdovitch [et al.] // - Health Phys. - 2020. - Vol. 118. - P. 170-184.

16. Estimation of the thyroid doses for Ukrainian children exposed in utero after the Chornobyl accident / I. Likhtarov [et al.] // Health Phys. - 2011. - Vol. 100. - P. 583-593.

17. Recall of diet during a past pregnancy / G. Bunin R [et al.] // - Am J Epidemiol. - 2001. - Vol. 154. - P. 1136-142.