I think people that laugh about others being afraid of radiation exposure are as unscientific as those that try to shield themselves from wifi networks. Nobody believes infrared radiation to be damaging, nobody believes their radio does any damage to them. And yet nobody would expose themselves to microwaves which are just between these frequency bands.
Even visible light can have an effect on you and I don't even mean the effect on your mood. It is prudent to perhaps not subject yourself to any frequency the electromagnetic spectrum has on offer.