To date the power absorbed by a unit mass of tissue (SAR) has been considered as the relevant parameter in assessing the risk caused by the exposure to radiofrequency electromagnetic fields. Anyhow, local SAR evaluation is only the first step to establish if a given exposure is safe from a thermal point of view. In fact, heating is strongly influenced not only by the power dissipated in a certain volume of tissue, but also by the thermal characteristics of the considered and neighboring tissues.

In this paper a complete electromagnetic and thermal analysis has been performed considering the head of a subject exposed to various kinds of cellular phones available on the market, and focusing the attention on important organs like the eye lens and the brain. First, attention has been posed on a particular phone model and a comparison between the absorbed power distribution and steady-state temperature increases has been carried out. The results show that the two distributions are not simply related due to the presence of heat exchanges among the tissues and to the blood perfusion. The influence of different antennas (dipole, monopole, whip, and PIFA) on the power absorption and on the consequent tissue heating has been finally analyzed.