Are full-body airport scanners safe?
The radiation exposure is extremely small, and the cancer risk has been called "truly trivial."
Safe is a tricky, eye-of-the-beholder word and concept. If safe means absolutely zero risk, then the answer to the "Are they safe?" question for scanners that use low-level x-rays is probably no. But if safe means a very small increase in risk — so small that a reasonable person shouldn't be seriously concerned about it — then the answer seems to be yes, they are safe, according to a persuasive article published in 2011 in Archives of Internal Medicine.
Two types of full-body scanners
The federal agency in charge of airport security, the Transportation Security Administration (TSA), started moving toward full-body scans for airplane passengers after Christmas Day 2009, when a young Nigerian man tried to blow up a plane headed for Detroit with a bomb hidden in his underwear.