Proposals to use X-ray scanners as part of airport security efforts are raising concerns about cancer risks. According to a recent New York Times report, some experts say the use of these X-ray scanners is certain to result in a few additional <"http://www.yourlawyer.com/practice_areas/diseases">cancer deaths.
The scanner risk for an individual scan from these machines, known as backscatter scanners, is negligible, as they deliver a dose of ionizing radiation equivalent to 1 percent or less of the radiation in a dental X-ray. But according to The New York Times, some experts believe the use of the scanners will “incrementally increase the risk of fatal cancers among the thousands or millions of travelers who will be exposed.”
In a 2002 report on the safety of backscatter scanners, the National Council on Radiation Protection and Measurements said it â€œcannot exclude the possibility of a fatal cancer attributable to radiation in a very large population of people exposed to very low doses of radiation.â€ An author of the report, David J. Brenner, a professor of radiation biophysics at Columbia and director of the universityâ€™s Center for Radiological Research, told The New York Times that risks might increase as airports begin using backscatter scanners as a first-line screening system.
Arjun Makhijani, a nuclear physicist, told the Times that if a billion passengers were screened with the dose assumed by the radiation protection council, that would mean 10 more cancer deaths a year. That number would represent only a tiny increase in the cancer death rate.
But others do not agree that the cancer rate would increase. Robert Barish, a radiation consultant in New York and the author of a 1996 book, â€œThe Invisible Passenger,â€ told the Times that the doses delivered by the scanners were tiny by any standard, and passengers would get the same dose in a few minutes in a high-altitude jet.
The Transportation Security Administration (TSA) says the dose from scanner is about the same amount as an average American receives from natural background sources in four minutes on the ground. A spokesperson for the agency told The Times that even for pregnant women, children and people whose genetic makeup made them more susceptible to X-ray damage, each person would have to undergo 1,000 screenings per year to exceed radiation standards.
There are other scanners that emit a lower dose of radiation. These are called millimeter wave scanners, and use less powerful, non-ionizing radiation that does not pose the same risk. But according to The New York Times, those scanners don’t produce images that are as sharp as those produced by backscatter scanners.
At any rate, it does look like a backscatter scanner could soon be headed to an airport near you. According to the Times, the TSA has already ordered a handful of the machines, and they could acquire another 450 by the end of September. And the TSA’s current contract for the machines could enable it to buy as many as 900.