"People are exposed to much more radiation from the sun, radon from the ground, radiation from industry and medical scanning than from these scanners," he said. "Of course, no radiation is better than radiation, but you have to weigh the pros and cons. I don't think the risks from these scanners is so great people should be hysterical about it and have this fear that prevents them from flying."
However, radiation expert Peter Rez, a professor of physics at Arizona State University in Tempe, found shortcomings in the study.
"I think they are correct that the radiation dose from the scanner is less than the radiation from the average flight, though I believe their numbers might be a factor of 10 too low," he said. "The real danger is what happens if the scans fail and there is a very high local dose," Rez said.
The key issue, said Rez, is this: "Is the risk, however small, worth it?"
"The question is not how the four excess cancers and one excess breast cancer compare with other sources of cancer, but how they compare with the risk of being killed by terrorists in an airplane," he said.
"According to my estimates, the risk from the scanner is low, about one in 30 million, the risk of dying from a terrorist attack on an airplane is equally low, if not lower, one in 30 million to one in 100 million," Rez said.
The TSA also permits passengers who don't want the body scan to undergo a physical pat-down.
For more information on scanner safety, visit the U.S. Transportation Safety Administration.
SOURCES: Rebecca Smith-Bindman, M.D., professor in residence, departments of radiology, epidemiology/biostatistics, and obstetrics, gynecology and reproductive medicine, University of California, San Francisco;
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