As part of its ongoing investigation of body scanners, ProPublica has written about their proliferation as law enforcement agencies around the country, including U.S. Customs and Border Protection and the New York Police Department, have begun using x-ray devices, sometimes covertly in unmarked vans. Other government agencies have done studies and are considering whether to deploy the equipment in the future.
Proponents claim that the amount of radiation from these devices is too low to be a danger, but research has shown the effects to be cumulative.
It is difficult to estimate the long-term health risks of low levels of radiation. At higher levels, ionizing radiation — the energy used in the scanners — has been shown to damage DNA and mutate genes, potentially leading to cancer. A comprehensive study by the National Academy of Sciences concluded that the more radiation a person gets, however little at a time, the greater their lifetime risk of dying from cancer.
Federal health regulations covering medical x-ray technology don’t apply to devices designed for security equipment and there is no mandatory safety standard set for the devices, only a voluntary standard set by the manufacturers and prospective users of the machines. Nor is there any way of keeping track of the equipment nationwide.
But the rapid expansion raises serious questions about whether the United States is sacrificing safety in the name of security.
“Because of the wide proliferation of these things, we don’t know who’s using them and how frequently,” said Peter Rez, an Arizona State University physicist who has criticized the use of the machines. “It’s not that the radiation from these machines is very high. It’s ‘Does the benefit outweigh the risk?'”