Security officials increasingly rely on full-body scanners to screen passengers, but could those machines pose a cancer risk to airline customers?

That's the word from several overseas media outlets this week, all of which report on a possible cancer risk from such machines.

The Daily Mail of London writes "experts say radiation from the scanners has been underestimated and could be particularly risky for children. They say that the low level beam does deliver a small dose of radiation to the body but because the beam concentrates on the skin -- one of the most radiation-sensitive organs of the human body -- that dose may be up to 20 times higher than first estimated."

"While the dose would be safe if it were distributed throughout the volume of the entire body, the dose to the skin may be dangerously high," University of California biochemist David Agard is quoted as saying by Australia's news.com.au. "Ionizing radiation such as the X-rays used in these scanners have the potential to induce chromosome damage, and that can lead to cancer," he adds.

Dr. David Brenner, chief of the center for radiological research at New York's Columbia University, tells the London Telegraph that while an individual's risk is "very low," the potentially large number of fliers going through full-body scanners could amplify that risk.

"If all 800 million people who use airports every year were screened with X-rays then the very small individual risk multiplied by the large number of screened people might imply a potential public health or societal risk," he tells the Telegraph. "The population risk has the potential to be significant."

The Toronto-based Digital Journal writes the scientists behind the warnings say "the skin around the face and neck are most at risk." Given that, Columbia's Brenner suggests to Australia's Herald Sun that "it would be prudent not to scan the head and neck" since it would be hard to hide weapons in those areas.

Despite those scientists' concerns, security officials insist the machines pose little risk to travelers.

Britain's Civil Aviation Authority tells the Daily Mail that "to put the issue in perspective, the radiation received from the scanning process is the equivalent to two minutes radiation received on a Transatlantic flight. Recent press publications have been a little alarmist and may have heightened concern in frequent travelers who may worry about their repeated exposure. Under current regulations, up to 5,000 scans per person per year can be conducted safely."

As for the U.S. reaction, the Digital Journal writes the "U.S. Transportation Security Administration (TSA) and Food and Drug Administration (FDA) officials have tried allaying concerns, claiming that people would have to take thousands of trips through the scanners to equal the dose from one X-ray scan in a hospital." However, the Digital Journal adds those agencies "have not addressed concerns raised by the researchers."