David Brenner, the head of Columbia University’s Centre for Radiological Research, says the concentration on the skin – one of the most radiation-sensitive organs of the body – means the radiation dose is actually 20 times higher than the official estimate.
Dr Brenner says the most likely risk from the airport scanners is a type of skin cancer called basal cell carcinoma, which mainly occurs on the head and neck and is usually curable.
The researcher was consulted to write guidelines for the security scanners in 2002 but said he would not have signed the report had he known the devices were going to be used so widely.
"There really is no other technology around where we're planning to X-ray such an enormous number of individuals," he said. “While individual risks will be extremely small, the population risk has the potential to be significant.”
The research also shows children are more vulnerable to radiation damage, because they have more cells dividing at any one time than when fully grown and a radiation-induced mutation can lead to cancer in adulthood.
