What makes you think the radiation is ionizing?
The full body scanners use RF energy in the Terahertz range, which is longer wavelength than the far-infrared end of the light spectrum, between 0.1 and 1mm approximately.
Ionization starts at a little above 3eV photon energy, which is the energy of ultraviolet light in the UVA band. The wavelength of UV light is from about 400nm downwards.
So in fact Terahertz radiation is a factor of about 250 times too low in photon energy to break chemical bonds and ionize anything.
Any limits on exposure to these frequencies are based on thermal effects rather than any other danger factor.
As for X-ray backscatter scanners, the dosage is claimed to be about 1/200,000th of the dosage given during a CT scan in hospital, so much lower risk that requiring a CT scan.
But if you want to complain, make it about the efficacy of the scanner when used to scan someone who has ingested or inserted explosives into a body cavity.
Last edited by Feathers McGraw; 9th Nov 2010 at 17:32.