FDTD computation of temperature rise inside a realistic head model for 1.5-GHz microwave exposure

The bioeffects of the electromagnetic fields of mobile telephones on the human body are a matter of concern, and the localized specific absorption rate (SAR) of the brain due to near-field exposure has attracted attention. Limiting the effects of radiofrequency electromagnetic fields on the human body to thermal ones, temperature rises are estimated to be caused by the SAR in the brain, including the body temperature-regulating center. In this paper, the temperature rises inside the brain due to exposure to 1.5-GHz microwaves are analyzed by the FDTD method, using a realistic model of the human head developed by the authors. It is found that the peak temperature rise occurs in the eye and muscle tissues. Such temperature rise is at most 0.35 degrees C at the safe exposure level of 5 mW/cm(2) specified in controlled environments in Japan. The rise in the hypothalamus, which regulates the temperature distribution over the human body, is only 0.0026 degrees C, which is two orders of magnitude smaller than its regulating induction-threshold of 0.3 degrees C. (C) 1998 Scripta Technica.