Personally I think the whole business of mobile phones and radiation is totally overstated, an 'expert' jumps up and expounds on a possibility which is then reported in the media and causes paranoia. Mobile phones transmit milliwatts of power at around 'microwave' frequencies, it's the phone mast that transmits power - but that is onidirectional (i.e. all around you) so you can't escape that anyway. The only real danger would be if you were right next to the mast antenna, the same for ANY powerful radio frequency transmitting antenna - you could suffer radiation burns.
I am a licenced radio amateur and have been using radio transmitters for many years at power levels up to 400 Watts at many different radio frequencies and bands sitting right in front of the transmitter and have not suffered any ill effects whatsoever. I also use a handheld radio which requires you to hold the set next to your mouth to speak and ear to hear the audio, it's capable of transmitting 10 Watts. There are a lot of radio amateurs who specialise in using microwave frequencies in the gigahertz regions at power levels far exceeding those of mobile phones, also suffering no ill effects.
So, for the pitiful power output of a mobile phone, I wouldn't give it a second thought or worry about it in the slightest.
