There is no doubt that hands-free kits for mobile phones represent a major breakthrough in something, but it may not be technology. Now any pedestrian muttering to him or herself is assumed to be juggling an active social life and a successful career. Now the Consumer Association reports that the only other remaining reason to acquire one, to protect your head from the microwave radiation emitted by phones, is invalid. It conjures up images of Hiroshima and Chernobyl. But there are many kinds of radiation.
Sunlight is radiation, for instance.
So it is with mobiles. The tiny pulses of microwaves emitted by mobile phones are of the same genre as the radiation used in microwave ovens to heat your frozen meals. It does heat your brain slightly, but if you tried to use your mobile to warm your cup of coffee, you'd be disappointed. There's just not enough power there, and the rise of temperature in the brain is less than you would get from using a hairdryer or, again, sunbathing. Despite centuries of research, the human brain is still a little understood, inaccessible organ.