Commenter Lab Rat does not understand what a Class 2B Possible carcinogen is. As the WHO later stated in its Fact Sheet No. 193 of October 2014 (see http://www.who.int/mediacentre/factsheets/fs193/en/): “To date, no adverse health effects have been established as being caused by mobile phone use.”

Sunlight is a Class 1 carcinogen (at least UV is), but I see no commenters here advocating blackout curtains on all classroom windows, mandatory sunscreen use, or rules that children only go outside wearing full-length UV-protective clothing and wide-brimmed hats.