Thyroid consequences of the Chernobyl nuclear power station accident on the Turkish population

Abstract

Objective: The Chernobyl accident caused widespread effects across Europe and huge areas were radiocontaminated. The major impact of the accident on human health was a sharp increase in childhood thyroid carcinoma and autoimmune thyroid diseases in exposed populations. The thyroidal effects of the Chernobyl accident have been investigated in most European countries, except Turkey. The aim of the current study was therefore to determine the thyroidal consequences of the Chernobyl nuclear power station accident in a selected Turkish population. Design: This study was designed as a sectional, area study, between October 2000 and March 2001, in two different regions of Turkey. According to the data of the Turkish Atomic Energy Authority, the eastern part of the Black Sea region was the most radiocontaminated area in Turkey at the time of Chernobyl accident, while Middle Anatolia was not seriously affected. Thus, Rize city, which is located in the eastern Black Sea region, served as a study area, and 970 adolescents, living in this region, comprised our study group (group R). On the other hand, Beypazarı, which is located in Middle Anatolia was choosen as the control region, and 710 adolescents living in this location were enrolled into the study as controls (group B). Methods: During the study, thyroid ultrasounds were performed in all subjects and thyroid volumes were calculated. World Health Organization and International Council for Control of Iodine Deficiency Disorders criteria were used for the determination of goiter. Thyroid fine-needle aspiration biopsy with ultrasound guidance was performed when a nodule was detected. Blood samples for thyroid function tests and thyroid autoantibodies, and urine samples for urinary iodine excretion were collected from all subjects. Results: Thyroid function tests were similar in both groups, but thyroid volumes were found to be higher in group B ð13:93^5:04 vs 17:66^5:58 ml; P , 0:001Þ: The prevalence of goiter was found to be 28.25% in group R and 61.95% in group B ðP , 0:001Þ: Thyroid nodules were determined in 6.28% of subjects in group R and 4.22% of subjects in group B ðP ¼ 0:065Þ: No malignant lesions were found in either of the regions. Although the percentage of autoantibody-positive subjects did not differ between groups (21.25% in group R vs 18.72% in group B), the mean antithyroglobulin level was found to be higher in group R ð63:25^378:60 vs 51:97^333:32 IU=ml; P , 0:001Þ and the mean anti-thyroid peroxidase level was higher in group B ð24:14^219:09 vs 48:82^568:50 IU=ml; P , 0:001Þ: The iodine status of the selected regions was found to be significantly different (median urinary iodine excretion was 131 mg/l in Rize and 54 mg/l in Beypazarı). Conclusions: Although there was a slight increase in nodule prevalence and thyroid antibody-positive subjects in the study group, it is hard to conclude that Turkey was affected by the Chernobyl accident. These results, at least the significant differences with regard to the prevalence of goiters between groups, m...

The rising trend of papillary carcinoma in thyroidectomies: 14-years of experience in a referral center of Turkey

“…In 2003, Emral et al [24] undertook a two-zone study in children who were aged under 5 years at the time of the Chernobyl accident and were living in the eastern Black Sea and inner Anatolia regions. This study pointed out that there was a slight increase in nodule prevalence and thyroid antibody-positive subjects in the Black Sea region.…”

“…As of 1999, mandatory iodization of household salt has been put into effect in Turkey. Three years after this policy, iodine-deficient regions became iodine-sufficient areas [24]. It is known that both iodine deficiency and iodine excess have a triggering effect in thyroid malignancies, especially with regard to papillary microcarcinoma in the case of mandatory iodization [25,26].…”

High Prevalence of Thyroid Dysfunction and Autoimmune Thyroiditis in Adolescents after Elimination of Iodine Deficiency in the Eastern Black Sea Region of Turkey

“…For the determination of goiter, World Health Organization and International Council for Control of Iodine Deficiency Disorders criteria were used. Thyroid volume over 13.9 ml in boys and 14.6 ml in girls for 14-year old adolescents and thyroid volumes over 16.0 ml in boys and 16.1 ml in girls for 15-to 18-year old adolescents were accepted as goiter (18,19).…”

Are Risk Factors Common to Thyroid Cancer and Nodule? A Forty Years Observational Time-Trend Study

“…In contrast, Drozd et al [23] reported that among 1,132 highly irradiated children (4–14 years old when exposed and 8–18 when investigated), the proportion of TN patients and the proportion of TC among TN patients were 1.2% and 50%, respectively, much higher than in the control unexposed population where a few benign nodules and no cancer were observed. In 2 studies, each comparing relatively contaminated areas far from Chernobyl, with a control group in more distant uncontaminated areas, no difference was found in children or adolescents, with a ratio of TN subjects/investigated subjects varying from 2% to 6% [24], [25]. Among children and adolescents exposed (0.79 grays) to 131 I after Chernobyl and evaluated 12 to 14 years later, TN was found in 2.7%, with 12% harboring TC [26].…”