Evaluation of Non-Thermal Microwave Effects on Bovine Lens by Measuring S-Parameters Induced by Variations in Dielectric Coefficient

This study evaluated the non-thermal effects of microwave on bovine lens by measuring the S-parameters induced by the dielectric coefficient variation in bovine lens. A closed, integrated biological experiment system was designed to expose bovine lens to microwave radiation quantitatively, and S-parameters were measured. Morphological evaluations were also performed during microwave radiation to evaluate the reaction mechanism of the non-thermal effects of microwave on the bovine lens. The results showed that the bovine lens became gradually cloudy and its refractive index changed significantly with increasing doses of microwave radiation. A comparison of experimental and control bovine lenses stained with hematoxylin and eosin revealed that the change in bovine lens might be a result of the nuclear fragmentation of lens epithelial cells and disorderly arrangement of lens fiber cells, which were induced by the vibration and friction of fiber tissues upset by microwave radiation. Further, the fluctuating decrements of 3.8 dB in S
₂₁
showed that the non-thermal effects of microwave could lead to the variations in the bovine lens dielectric coefficient. These findings suggest that the dielectric coefficient may quantitatively describe the physiological state of bovine lens. This study might be the valuable reference for the establishment of new electromagnetic radiation safety standard.