ID Number		542
Study Type		Engineering & Physics
Model		30 MHz - 3 GHz exposure and modeling of SAR distribution and surface heating using Japanese anatomical models of children and adults
Details		Experimental and numerical methods used to investigate the effects of ear-shape, head-size, and hand-holding on the SAR in a human head during use of a mobile phone. For assessment of SAR in children's heads, several realistic child head models were developed by scaling down an MRI-based Japanese adult head model. The authors report spatial peak SARs in adult and child heads depend largely on antenna input impedance. An empirical formula for the complex permittivity of various tissues as a function of ages according to the total body water was proposed based on Lichtenecker exponential law and measured data. Modeling data revealed that childrens dielectric properties do not significantly affect the spatial peak SAR or penetration depth. In a subsequent paper (2006), the authors again employed FDTD with more sophisticated assumptions to calculate whole body SAR for a representative Japanese adult and child exposed to RF at the ICNIRP limit from 30 MHz to 3 GHz. They report that at some frequencies, notably ~ 2 GHz, the SAR exceeds the ICNIRP basic limit of 0.08 W/kg for public exposure, and that this is more pronounced in the child. The authors also report that these results support similar results from Dimbylow et al. A very interesting study ongoing by Varsier and Watanabe (reported in South Africa, October 2007) attempts to classify mobile phone users for Interphone and other epi studies by general phone type, use position, and peak SAR into a manageable set of exposure categories.
Findings		Not Applicable to Bioeffects
Status		Completed With Publication
Principal Investigator		Nat'l Inst Information Comm Tech, Tokyo Japan - wata@nict.go.jp
Funding Agency		MIC, Japan
Country		JAPAN
References		Wang, J et al. Phys Med Biol, (2006) 51:4119-4127 Mochizuki, S et al. Electronics and Communications in Japan, (2004) J-85B:640-648 Watanabe, S et al. IEEE Trans. Microwave Theory Tech., (1997) 44:1874-1883 Watanabe, S et al. International Symposium on Electromagnetic Compatibility, Tokyo, Japan, (1999) :341-344
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