ABC World News is reporting on whether radiation exposure from full-body scanners to be implemented by the Transportation Security Administration (TSA) pose health risks for passengers. ABC’s Betsy Stark noted, “Most of the scanners about to be deployed in the US use x-rays to look for objects hidden under clothes.”
While exposure to x-rays, to radiation, can increase the risk of cancer, according to the machine’s manufacturers, and (even more importantly) an independent study … the scanners pose little to no health risk.
The Los Angeles Times “Booster Shots” blog reported that for its part, “the American College of Radiology has issued” an official statement that the group “is not aware of any evidence that either of the scanning technologies that the TSA is considering would present significant biological effects for passengers screened.”
Reuters reports that James Thrall, MD, FACR, of the American College of Radiology and chief of radiology at Massachusetts General Hospital, said, “All of the concerns that we have about the medical use of X-rays really don’t apply to” the two types of scanners, millimeter wavelength imaging and backscatter X-ray scanners, because “the exposure is extremely low.”
Here’s the full ACR statement:
Amid concerns regarding terrorists targeting airliners using weapons less detectable by traditional means, the Transportation Security Administration (TSA) is ramping up deployment of whole body scanners at security checkpoints in U.S. airports. These systems produce anatomically accurate images of the body and can detect objects and substances concealed by clothing. To date, TSA has deployed two types of scanning systems:
- Millimeter wave technology uses low-level radio waves in the millimeter wave spectrum. Two rotating antennae cover the passenger from head to toe with low-level RF energy.
- Backscatter technology uses extremely weak X-rays delivering less than 10 microRem of radiation per scan ─ the radiation equivalent one receives inside an aircraft flying for two minutes at 30,000 feet.
An airline passenger flying cross-country is exposed to more radiation from the flight than from screening by one of these devices. The National Council on Radiation Protection and Measurement (NCRP) has reported that a traveler would need to experience 100 backscatter scans per year to reach what they classify as a Negligible Individual Dose. The American College of Radiology (ACR) agrees with this conclusion. By these measurements, a traveler would require more than 1,000 such scans in a year to reach the effective dose equal to one standard chest x-ray.
The ACR is not aware of any evidence that either of the scanning technologies that the TSA is considering would present significant biological effects for passengers screened.
“A passenger would need to be scanned using a backscatter scanner, from both the front and the back, about 200,000 times to receive the amount of radiation equal to one typical CT scan,” Dr. Andrew J. Einstein, director of cardiac CT research at Columbia University Medical Center in New York City reported Business Week.
“Another way to look at this is that if you were scanned with a backscatter scanner every day of your life, you would still only receive a tenth of the dose of a typical CT scan,” he said. By comparison, the amount of radiation from a backscatter scanner is equivalent to about 10 minutes of natural background radiation in the United States, Einstein said. “I believe that the general public has nothing to worry about in terms of the radiation from airline scanning,” he added.
For moms-to-be, no evidence supports an increased risk of miscarriage or fetal abnormalities from these scanners, Einstein added. “A pregnant woman will receive much more radiation from cosmic rays she is exposed to while flying than from passing through a scanner in the airport,” he said.
Despite all these reassurances, if you are pregnant, or traveling with children, and want to avoid any exposure to these x-rays, simply opt out. You can ask TSA for a full-body pat down.