This section of the EM spectrum is non-ionizing. So unlike, say, X-rays, you won't get cancer as the waves aren't strong enough to strip an electron off an atom

This section of the EM spectrum is non-ionizing. So unlike, say, X-rays, you won't get cancer as the waves aren't strong enough to strip an electron off an atom and therefore change your DNA. However, they will heat your cells to some degree (since 2.5GHz is the same freq as a microwave). This can cause cataracts over long exposure to high enough power as your eyes can't regulate heat.