Study of histopathological effects of electromagnetic field (EMF) on the thyroid gland of rats

The relationship between exposures to Electromagnetic field (EMF) and human health is more in focus. Some studies showed the possible relation between exposure to EMF and cancer. The thyroid gland is one of the most exposed and vital organ and may be a target for any type of electromagnetic radiation; therefore, we studied histopathological effects of electromagnetic field (EMF) on the thyroid gland of rat. In this research, 35 healthy rats were used. The animals were divided to five groups, and then all animals were exposed to 2100MHz (4G) frequency for 0, 15, 60, 120, 180 min every day for a period of 70 days. The animals were euthanized by removing of blood from the heart then tissue samples were prepared from thyroid gland and stained with hematoxylin and eosin (H&E) and Mason trichrome (MT). Stereological studies were done by the Cavalier’s principle. Following the EMF exposure, a significant decrease (p < 0.05) in the diameter of the thyroid follicles, heights of epithelial follicles and thyroid follicles volume were recorded in 180 min exposure groups.In the EMF exposure groups (120 and 180 min) histopathological effect observed include follicles with decreased colloid, congestion and increase of connective tissue. We also observed formation of apoptotic body that infiltrated inside of follicle and follicular cells with condensed nuclei under the exposure of EMF for120 and 180 min.We concluded that exposure of EMF (4G) for over 120 min for 70 consecutive days has histopathological and stereological effects in thyroid gland in rats.