I don't use a phone often enough to worry about radiation from it

"Radiation" from mobile phones is not the same as radiation from X-rays or nuclear power or your old telly cathode-ray tube or your smoke alarms. They are all emitting ionising radiation that can smash up your DNA if you let it. Mobile phones and microwave ovens emit non-ionising radiation, an inconvenient fact that the scaremongers usually neglect to apprise you of.