There's already loads of millimeter wavelength gear deployed : P2P links between buildings; TSA machines at airports. So..although some caution is of course appropriate, it isn't like this stuff isn't already irradiating humans widely.

Disclosure : based on my understanding of EM radiation as an EE and person who deploys microwave gear around my own house, I'm fine with anything non-ionizing. I'd like to see the general public more educated on this subject. Obfuscation is not in anyone's interest.