Distribution of RF energy emitted by mobile phones in anatomical structures of the brain

TLDR

Mobile phone use has risen sharply worldwide, raising concerns that RF exposure may increase cancer risk, especially for tumors in brain regions with the highest energy absorption. This study aims to map the spatial distribution of RF energy in the human brain using measurements from 110 phones used in Europe and Japan. The authors measured the specific absorption rate (SAR) per unit mass (W kg⁻¹) in brain tissue to quantify energy deposition. The analysis shows that 97–99 % of RF energy is absorbed in the hemisphere where the phone is held, with 50–60 % concentrated in the temporal lobe, SAR peaking 6–15 % in the temporal lobe and 2–10 % in the cerebellum, rapidly declining with depth, and exhibiting similar patterns across phone models, underscoring the importance of tumor location in risk assessments.

Abstract

The rapid worldwide increase in mobile phone use in the last decade has generated considerable interest in possible carcinogenic effects of radio frequency (RF). Because exposure to RF from phones is localized, if a risk exists it is likely to be greatest for tumours in regions with greatest energy absorption. The objective of the current paper was to characterize the spatial distribution of RF energy in the brain, using results of measurements made in two laboratories on 110 phones used in Europe or Japan. Most (97–99% depending on frequency) appears to be absorbed in the brain hemisphere on the side where the phone is used, mainly (50–60%) in the temporal lobe. The average relative SARSAR is the specific energy absorption rate i.e. energy absorption rate per unit mass (measured in W kg−1). is highest in the temporal lobe (6–15%, depending on frequency, of the spatial peak SAR in the most exposed region of the brain) and the cerebellum (2–10%) and decreases very rapidly with increasing depth, particularly at higher frequencies. The SAR distribution appears to be fairly similar across phone models, between older and newer phones and between phones with different antenna types and positions. Analyses of risk by location of tumour are therefore important for the interpretation of results of studies of brain tumours in relation to mobile phone use.