I really wouldnt worry about EM radiation, parts from the whole spectrum pass through you everyday and the only ones that actually get emitted from wifi routers are radio waves anyway!!
They are designed to work to the same guidelines as radio frequency safety standards which therefore makes WLANs safe.
Just for your info, i got this off some website (i can't remember which): These standards and recommendations reflect the consensus of the scientific community and result from deliberations of panels and committees of scientists who continually review and interpret the extensive research literature.
Feel Safe!!
