Privacy issues aside (if you’d like to read a blog about the violations of the airport scanners, take a look at NimblePig‘s blog), how unhealthy are those scanners at the airport?
According to Dr. Jane Orient of the AAPS, “An acute dose of less than 100 rads probably wouldn’t make you sick. A dose between 300 and 400 rads causes acute radiation sickness and a 50% chance of death. There’s a widespread belief that the teeniest dose might increase your risk of getting cancer in 20 years, say adding 1% to the 25% risk you have anyway, but there is also much evidence that low doses are actually protective.”
Dr. Orient also added “If I worked for TSA, I’d have a SIRAD in my pocket. Agents used to be issued dosimeters.”
So how much radiation do you get from a scanner? I found a few key things from various studies and articles:
1. When the Transportation Security Administration (TSA) began rolling out the so-called backscatter machines in March, the agency, along with the Food and Drug Administration (FDA) and the National Institute of Standards and Technology, assured the public that the radiation dose from a scan was negligible–far lower not only than the amount in a chest X-ray but also than the levels passengers absorb from cosmic rays on a cross-country flight.
The problem with item 1 is that “the backscatter numbers seemed too good to be true to several scientists, including John Sedat, a biophysics professor at the University of California, San Francisco. After studying the degree of detail obtained in the seconds-long scans, the scientists wondered how the radiation exposure could be so low. The answer, they concluded, lay in how the manufacturer and government officials measured the dose: by averaging the exposure from the beam over the volume of the entire body. This is how scientists measure exposure from medical X-rays, which are designed to zap straight through bone and tissue. But backscatter beams skim the body’s surface. Sedat and his colleagues maintain that if the dose were based only on skin exposure, the result would be 10 to 20 times the manufacturer’s calculations.”
2. The Allied Pilots Association, the pilot’s union, publicly advised its members — who are scanned two to three times per day during the course of their work — to opt for private pat-downs instead of the scan.
That should tell you something right there. But looking for some numbers, I found some on HealthLand:
1. Smoking: 400 to 3,900 mrem
2. Medical Imaging: 10 to 10,000 mrem
3. Air Travel: 26 mrem (6 from the flight, 10 from each pass through security)
4. Watching TV: 1 mrem
By the way, 1 mrad = 0.001 rad. It would take a LOT of trips through airport security all in-a-row to give you any kind of accute sickness. Depending on how often you travel and how much TV you watch, you may bemore likely to get radion sickness from the TV. If anyone knows of other data on mrads from airport security, I’d love to see it becuase this seems very low to me for all the worry it has caused.