The most dangerous frequencies of electromagnetic energy are X-rays, gamma rays, ultraviolet light and microwaves. X-rays, gamma rays and UV light can damage living tissues, and microwaves can cook them.
five gee towers are microwave transmitters. These frequencies are extremely dangerous in anything but the smallest amplitudes (power levels)... there's a reason that uwave ovens have interlocks and shielding on their doors! Personally, I don't believe that the massive push to implement this is entirely altruistic just so that we can download a video to our cellphone more quickly. Brits have an excellent term for this reasoning... RUBBISH.
Ultrasound (piezoelectric) phased array antennas?
