I find those study very very disturbing. Not because it's a health issue, but more about creating propaganda.
There are many different types of radiation exposures, the 2.4Ghz devices we have, are non-ionizing, that means it will not pose the risk for cancer. X-Ray on the other hand is ionizing, therefore prolonged exposure will cause cell degradation.
Also, 2.4Ghz routers only gives out less than 120mW of power (typically 70-90mW). Unless you are wearing it on your head everyday, chances of getting killed is very unlikely. Cordless phones generate about 120-180mW, that's still not even enough to kill you.
Unlike a cell phone, where it transmits as much as 3W. There is more danger on a cell phones than Wifi.
Do I need to mention our microwave oven? They generate even more... 700W to 1000W these days.
