Just to be clear, I don't think that low-power EM radiation poses a health risk. I am just saying that if you are worried about it (like OP is) you can simply reduce your exposure to it. Doing so is relatively easy and with a minimal quality of life impact. As others have mentioned, low-power EM radiation in the frequency range used by cellphones is non-ionizing, so it can't cause cancer or severe health issues in the same way that ionizing radiation can.