Age Dependant Tissue-Specific Exposure of Cell Phone Users

Abstract

The peak spatial specific absorption rate (SAR) assessed with the standardizedspecific anthropometric mannequin head phantom has been shown to yielda conservative exposure estimate for both adults and children using mobilephones. There are, however, questions remaining concerning the impact ofage-dependent dielectric tissue properties and age-dependent proportions ofthe skull, face and ear on the global and local absorption, in particular in thebrain tissues. In this study, we compare the absorption in various parts ofthe cortex for different magnetic resonance imaging-based head phantoms ofadults and children exposed to different models of mobile phones. The resultsshow that the locally induced fields in children can be significantly higher(>3 dB) in subregions of the brain (cortex, hippocampus and hypothalamus)and the eye due to the closer proximity of the phone to these tissues. Theincrease is even larger for bone marrow (>10 dB) as a result of its significantlyhigh conductivity. Tissues such as the pineal gland show no increase since theirdistances to the phone are not a function of age. This study, however, confirmsprevious findings saying that there are no age-dependent changes of the peakspatial SAR when averaged over the entire head.

Download the full study below.