One-year follow-up of thyroid status in rats exposed to 2.45 Ghz radiofrequency radiation during the prenatal period

The aim of this study is to investigate the thyroid status of offspring exposed to prenatal 2.45 GHz radiofrequency radiation (RFR). In this study, which is the second phase of our previous study, the thyroids of rats exposed to prenatal 2.45 GHz RFR were examined one year after birth. The mothers of the offspring in the experimental group (<i>n</i> = 8) were exposed to 2.45 GHz RFR (whole-body specific absorption rate (SAR): 12 mW/kg; maximum point SAR: 25 mW/kg) 24 hours per day throughout pregnancy. The mothers in the sham group (<i>n</i> = 8) were kept under the same experimental conditions except for RFR exposure. The offspring in this study were not exposed to RFR after birth and continued their daily lives for one year. When the offspring reached one year of age, they were sacrificed and their thyroids were removed and evaluated. Mann-Whitney U and t tests were used for statistical analysis. Increases in fibrosis (<i>p</i> = 0.038), atypical thyrocytes (<i>p</i> = 0.002) and degenerated follicles (<i>p</i> = 0.007) and colloid reduction (<i>p</i> = 0.002) were found to be significant in the experimental group compared to the sham group. However, the increase in the percentage of apoptosis positive cells (<i>p</i> = 0.006) and H2A.X antibody levels (<i>p</i> = 0.007) showed a statistically significant difference in the experimental group compared to the sham group. This study provides evidence that prenatal exposure to 2.45 GHz RFR can induce persistent histological changes, increase apoptosis, and cause DNA double-strand breaks in thyroid tissue observed one year after birth. These results underscore the importance of further long-term studies to assess developmental risks associated with prenatal RFR exposure.