Varsier N , Wake K, Taki M, Watanabe S, Takebayashi T, Yamaguchi N, Kikuchi Y. (2008): SAR characterization inside intracranial tumors for case–control epidemiological studies on cellular phones and RF exposure. Annals of Telecommunications. 63(1-2):65-78.
Background and Objective
Evaluation of exposure to radiofrequency radiation has always been a concern in epidemiological studies of mobile phone use and cancer. The purpose of this study was to introduce a dose metric in the exposure assessment, taking into account spatial distribution of exposure.
Based on SAR distributions and technical specifications, mobile phones were classified into four categories. SAR distributions were estimated inside 275 cases of brain tumors in the participants of the Japanese case-control epidemiological study on mobile phone use and the risk of brain cancer. This epidemiological study is a part of the international collaborative case-control study (INTERPHONE).
SAR distributions inside the tumors were shown to be dependent on the phone categories. For any phone category, the maximum SAR in the contralateral tumors was less than 2.5% of the maximum SAR in the brain. For any phone category, the maximum SAR in 75% of the ipsilateral tumors was less than 15% of the maximum SAR in the brain. Three new exposure indices were created for use in epidemiological studies.
Interpretation and Conclusion
Epidemiologists usually categorize contralateral tumors as non-exposed, and the study results confirm this categorization. The maximum SAR in the ipsilateral tumors was far below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) safety limits concerning localized SAR.