Abstract
OBJECTIVE: This study aimed to evaluate long-term skin histomorphometry at 18 months postpartum in rats exposed in utero to 3.5 GHz radiofrequency radiation (RFR). METHODS: Pregnant Wistar Hannover rats were exposed to Global System for Mobile Communications-modulated 3.5 GHz RFR for 2 h/day throughout gestation, while the sham group underwent mock exposure. Offspring (n=5 per group) were not exposed to any further RFR until 18 months after birth. Dorsal skin samples were stained with hematoxylin-eosin and Masson's trichrome, and dermal thickness, adipose tissue area, dermal area, adipose/dermis ratio, and fat percentage were quantified. Specific absorption rate (SAR) was calculated using CST Studio Suite. Data were analyzed using the Student's t-test or the Mann-Whitney U test. Statistical significance was defined as p<0.05. RESULTS: The peak spatial SAR (psSAR) values were 0.06622 mW/g (for 1 g) and 0.03825 mW/g (for 10 g). No statistically significant differences were observed between RFR-exposed and sham groups in dermal thickness (655.32±87.46 μm vs 544.42±135.01 μm); fat area percentage (0.73±0.29% vs 0.66±0.22%); dermal area (1.05±0.17 vs 0.88±0.22); adipose/dermis ratio (1.78 ± 0.24 vs 1.54±0.28); or fat percentage (40.04±11.78% vs 42.96±11.60%) (all p>0.05). CONCLUSIONS: Prenatal exposure to 3.5 GHz RFR did not cause significant skin histomorphometric alterations in the dermis of aged female rats. The skin's barrier properties, regenerative capacity, and repair mechanisms may mitigate long-term structural effects of such exposures.