So what
Radio waves are a type of electromagnetic waves that operate at around 10^4hz. This frequency has a small chance of causing cancer if the skin comes in direct contact with the receiver or the transmitter. But now days phones are cased better and the chance of actually getting cancer is a lot smaller. Along side cancer these rays can cause burns. Keep in mind these are extreme effects and because they are non-ionizing rays the possibility of these rays harming you are quite low. Any thing that emits ionizing rays will harm you a lot more directly. You are more likely to damage your eyes then you are to get effected by the waves.
Phones use radio waves so...
Aenean porttitor cursus fermentum sed mauris nunc, laoreet ut scelerisque