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Transportation Biotech Privacy Security Science

Scientists Question Safety of New Airport Scanners 357

An anonymous reader sends this quote from a story at NPR about the accelerated deployment of new scanning machines at airports: "Fifty-two of these state-of-the-art machines are already scanning passengers at 23 US airports. By the end of 2011, there will be 1,000 machines and two out of every three passengers will be asked to step into one of the new machines for a six-second head-to-toe scan before boarding. About half of these machines will be so-called X-ray back-scatter scanners. They use low-energy X-rays to peer beneath passengers' clothing. That has some scientists worried. ... The San Francisco group thinks both the machine's manufacturer, Rapiscan, and government officials have miscalculated the dose that the X-ray scanners deliver to the skin — where nearly all the radiation is concentrated. The stated dose — about .02 microsieverts, a medical unit of radiation — is averaged over the whole body, members of the UCSF group said in interviews. But they maintain that if the dose is calculated as what gets deposited in the skin, the number would be higher, though how much higher is unclear."
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Scientists Question Safety of New Airport Scanners

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  • Reason #76 (Score:5, Insightful)

    by Itninja ( 937614 ) on Monday May 17, 2010 @01:47PM (#32241802) Homepage
    To never use commercial airflight again.
    • by godrik ( 1287354 )

      I wish I had the choice. I travel for work between the us and europe at least 4 times a year. Taking a boat is not really a comparable solution...

  • Need a vascectomy? Fly the friendly skies instead! The more miles you log, the fewer kids you'll spawn!
    • by blueg3 ( 192743 )

      This is already true, without the X-ray imagers. In fact, a scan from the imager only gives you radiation equivalent to a few minutes in an airplane -- the flight itself does a much better job.

  • Idiotic (Score:5, Insightful)

    by FrankSchwab ( 675585 ) on Monday May 17, 2010 @01:50PM (#32241860) Journal

    Regardless of the health issues, why should I be electronically strip-searched when the next terrorist is going to shove explosives up his ass and remove/detonate them during flight?

    What invasion of privacy is going to happen after that event?

    • Re:Idiotic (Score:5, Funny)

      by Shakrai ( 717556 ) * on Monday May 17, 2010 @01:51PM (#32241900) Journal

      What invasion of privacy is going to happen after that event?

      I'm not sure but I suspect that K-Y Jelly will be involved.

      • Re:Idiotic (Score:4, Funny)

        by B2382F29 ( 742174 ) on Monday May 17, 2010 @01:55PM (#32241980)

        I'm not sure but I suspect that K-Y Jelly will be involved.

        If you're lucky... I think you'll get the K-Y Jelly in first class only...

      • Washington, DC - Newly installed director of the FBI, Warren B. Upass, has announced a registry for all K-Y jelly and related "intimate lubricants".

        "Clearly," Upass said in a recent press release, "the terrorists who threaten our fine, upstanding heterosexual way of life will be shoving bombs up their anuses. We need to be one step ahead of the terrorists. From now on every purchaser of intimate lubricants will have to provide their name, phone number and nearest cheap motel to the FBI. In the meantime,

    • by h4rr4r ( 612664 )

      What do you think?
      Electronic orifice scanning.

  • Nobody cares (Score:5, Insightful)

    by TheMeuge ( 645043 ) on Monday May 17, 2010 @01:50PM (#32241874)

    There's already been studies looking at changes in gene expression following millimeter-wave irradiation of skin: http://www.ncbi.nlm.nih.gov/pubmed/18302488 [nih.gov]

    Overall, given the reviews of the literature it's still unclear whether there's a potential for long-term health damage.

    However, even if there was, I doubt anyone will care. The security theater must be kept up, even if it means that people would be harmed by repeated exposure.

    "Sir, we will protect you from yourself, even if it kills you".

    • itis not the same (Score:4, Informative)

      by aepervius ( 535155 ) on Monday May 17, 2010 @02:00PM (#32242074)
      Backscatter x ray is *not* the same as millimeter wave. Millimeter wave is about of the order of magnitude of milli-electron volt and not an ionizing radiation energy. OTOH x ray is at least on the order of magnitude from 100 electron volt and is definitively an ionizing radiation. There is a reason they were measuring the amount of radiation absorbed in millisievert, whereas for millimeter wave scanner there is no concern (around near infrared).
      • Can someone tell me about the scanners for containers in ports? My neighbor is a trucker, and he asked me about that. Apparently, as the driver, he has to go through the scanner himself pretty frequently (it's the port of Oakland in California if that makes a difference).

        • There's an article here [thedigitalship.com] from a few years ago that says they're either gamma or high-energy x-ray scanners. I'm no medic, but I'd be inclined to think that powerful ionising radiation sources like that are the kind of thing you'd do well to avoid.

          Oddly, though, despite the fact that the article subtitle poses the question "do they cause any harm to personnel?", I don't actually see any reference to an answer in the text.

      • Thanks for correcting me. I'm writing my thesis, so my brain is deep-fried.

        • I remember writing mine, by the end I was very brain adled. But I look back at that time with fondness :). Afterward it can get even worst trying to find a post doc :p.
    • Re:Nobody cares (Score:5, Informative)

      by phantomfive ( 622387 ) on Monday May 17, 2010 @02:13PM (#32242348) Journal
      On thing the article points out is that the level of x-ray radiation you receive during your flight (because of the high altitude) is going to be higher than the amount of radiation you're going to get from the scanner. Essentially spending 4 minutes at cruising altitude will expose you to the same level as the machine.

      Also, the average person in the average year receives 3,000 microsieverts of radiation just from the environment (cosmic radiation, etc). So the .02 received from the machine is probably negligible, unless it really is significantly concentrated in certain places on the skin.
      • Re: (Score:3, Insightful)

        by dgatwood ( 11270 )

        Who cares? Radiation exposure is cumulative. And high altitude flying is basically unavoidable; these stupid little machines aren't.

        Saying that it doesn't matter because you're exposed to more of it in your daily life is like saying that picking up a possibly-loaded revolver, putting it up to your head, spinning the cylinder, and pulling the trigger on Cinco de Mayo is not dangerous because people are shooting guns up in the air anyway and one of those bullets might hit you. What matters is not the milli

        • Re: (Score:3, Informative)

          by phantomfive ( 622387 )

          Saying that it doesn't matter because you're exposed to more of it in your daily life is like saying that picking up a possibly-loaded revolver, putting it up to your head, spinning the cylinder, and pulling the trigger on Cinco de Mayo is not dangerous because people are shooting guns up in the air anyway and one of those bullets might hit you.

          If you look at the levels of radiation involved, it is more like walking across the street an extra time today, even though that does add a small degree of extra risk to your day. We're talking about less than .0007% of your total annual radiation. It's good to be aware, but you need to learn to keep things in perspective.

          I don't think these devices will stop terrorists, but they are more likely to catch a terrorist than you are to die from radiation from them.

          • Re: (Score:3, Insightful)

            by phantomfive ( 622387 )
            I should add that my statement assumes the .02 microsieverts figure is correct, obviously if we find out there are 100 microsieverts focused on a particular part of the body, that changes things.
        • Re: (Score:3, Interesting)

            Indeed; if these exposures are safe - even for frequent flyers, then why have we been repeatedly warned over the last thirty+ years about cumulative exposure to xrays in dentist and doctors offices?


      • Re: (Score:3, Informative)

        The point however is what tissue received the dosage. In the backscatter cases its a thin layer of skin. While in the normal Xray or at high altitude (not xrays by the way) its the whole body.

        The problem is that they quote the scanner dose as if the whole body is absorbing the xray energy. Thus the does level measured in this misleading way for a increased chance of cancer is much much lower.

        For example if the whole dose is absorbed by just a 1 millimeter of skin, thats probably less than 100th total
    • I strongly doubt millimeter wavelength radiation (somewhere around microwave/low IR) is going to cause any problems unless it's at such high magnitude that it actually causes tissue heating. These scanners probably operate at 1-10nm. Very high energy. Even at very low intensity, X-ray radiation imposes some risk of DNA damage. But I'd probably be more concerned about cataracts in frequent flyers and airport security employees. http://lowdose.energy.gov/abstracts/kleiman_cataract.aspx [energy.gov]
  • by Ryvar ( 122400 ) on Monday May 17, 2010 @01:50PM (#32241876) Homepage

    I don't honestly care whether there's a real medical issue here. I don't care if it takes Fox News-style "gotcha" tactics to make the hysterical cries of "THINK OF THE CHILDREN" echo up and down the corridors of the powerful.

    Anything that kills this program needs to be seized upon, hyped, spun into something it's probably truthfully not - the lies and paranoia that have been eating away at us like a cancer need to be repurposed toward actually helping us.


  • by jacks smirking reven ( 909048 ) on Monday May 17, 2010 @01:53PM (#32241942)
    As someone who has done a fair share of work in airports (digital signage) and has been badged in a couple of term, I can say this from observation and from talking to people in the airports and the TSA, the issue is not the passengers, it's the workers. The passengers are checked to ridiculous measures, but if you work at an airport your protocols are entirely different. All the tarmac entrances and any "employee only" entrance isn't guarded by the TSA, but rather independent security companies hired by the airports themselves, so every airports strictness at these points are anywhere from stricter or far more lax, especially if you're a regular employee that they recognize. I have had to throw gear into the back of an electricians truck many many a time and driven it onto the tarmac without them opening or even swabbing the boxes. At that point I am less then 30ft away from a 767.

    All this extra effort at the checkpoints is to keep up what most people here already know what it is. The illusion of absolute safety in a system where it can never be guaranteed 100%.
    • by Shakrai ( 717556 ) * on Monday May 17, 2010 @02:10PM (#32242280) Journal

      The passengers are checked to ridiculous measures, but if you work at an airport your protocols are entirely different

      That's an understatement. I have a friend who used to work at the local airport. I've been on behind the scenes tours with him and the security folks (ranging from TSA, to law enforcement to rent-a-cops) never even batted an eyelash when he took me past the checkpoint. They didn't ask me to go through the metal/explosives detectors or to wear a guest badge of some sort. We just walked right past them and my friend says "He's with me." Granted, this is a small town airport with not a lot of activity (three flights per day) but the ease with which it was possible to get into the secured areas seemed to make a mockery of all the FUD we've been fed about airport security. It occurs to me that if somebody wanted to do bad things he could just buy off the right person(s) at the airport to gain access.

    • by Lumpy ( 12016 )

      Dude, you realize that all I have to do is go to one of the private or corporate hangers and dress correctly and I can get on the tarmac without anyone even questioning me?

      I was dressed wrong, had my tool box and a huge cardboard box of equipment that I walked from Hangar A to the other side past commercial aircraft and nobody even stopped to ask me what I was doing.

      airport security, even at O-hare is a utter joke. It's not just theater, it's cardboard cutouts.

    • Here is an example of airport workers arrested for smuggling drugs, guns and even grenades on airplanes. And this was in 1999.

      http://articles.sfgate.com/1999-09-10/news/17698252_1_undercover-agents-baggage-handler-smuggling [sfgate.com]

      Security of any system is based upon the strength of the weakest link.

  • Next on Fox... (Score:5, Insightful)

    by fuzzyfuzzyfungus ( 1223518 ) on Monday May 17, 2010 @01:53PM (#32241944) Journal
    "Why Does Liberal Academia Hate Security?"
  • but i read somewhere that the simple act of flying is equivalent to getting an x-ray because you're so high in the atmosphere

    i also read that living in denver for a year is equivalent to getting an xray (as compared to living in say miami: at sea level, rather than a mile up)

    not that i'm justifying these scanners, but if you're worried about extra unnecessary irradiation, then don't fly (or live in the mountains)

    its too much of a hassle anyways, even without the scanners, flying sucks

    • Re:i could be wrong (Score:5, Informative)

      by Ultimate Heretic ( 1058480 ) on Monday May 17, 2010 @02:04PM (#32242176)
      You are correct. One of the highest radiation dose jobs in the world is pilot, followed by co-pilot and flight attendant. This is drilled into those taking radiation safety courses. Of course, one must be aware of the different affects the specific energy particles/rays have on DNA to give a complete picture of the long term hazards. Interestingly enough, the NPR piece, which had an expert stating that they were not worried about excessive x-ray dosages from equipment malfunction, was immediately followed by one on the accidental excessive x-ray doses from medical scanners. Whoops!
    • Surely if you're already getting a hefty dose of radiation every time you fly, the last thing you want to do is give someone another hefty dose of radiation.

    • I seem to recall the party line is that the radiation from one of the scanners is about two minutes of flight time. Of course the government would never lie to use or misstate facts, would it?

      We need to kill this thing but I don't think we can do so on safety grounds. Better to appeal to genital insecurity and think of the children panic, in my mind.

  • by ThreeGigs ( 239452 ) on Monday May 17, 2010 @01:59PM (#32242040)

    Cosmic rays at 30,000 feet, plus other ionizing radiation is significantly higher than at ground level. 4 hours on a plane is something like a month's worth of ground-level exposure. Yet people still fly. I don't think this will have any impact on air travel.

    • Re: (Score:3, Interesting)

      by dgatwood ( 11270 )

      Quit exaggerating. The background radiation level doubles every 6,000 feet, so an entire 24-hour day at 30,000 feet is like a month on the ground. A four hour flight is roughly the equivalent of 5 days on the ground.

      Also, remember that radiation exposure is considered cumulative. There is no safe level of radiation exposure. The more you are exposed to, the greater your risk of death, period. Thus, it is utterly irrelevant whether the backscatter machine only adds... say a tenth as much radiation as th

    • by guruevi ( 827432 )

      Even though you're sitting in a Faraday cage? Citation please! I'll take one of my wife's x-ray badges next time I go through the airport, they will be analyzed to see if you've been exposed to an unhealthy amount of x-ray radiation.

  • Who are going to involuntarily contract google-itis from this. :'-(
  • A couple of orders of magnitude more for the average flight. That would be whole-body, not skin.
  • If you don't mind to die, then what's to stop you from hiding a few sticks of C4 (with ceramic shrapnel, of course) inside your body by, you know, having a surgeon sew it in? Stick a simple fuse triggered by a Hall sensor into it, and carry an inconspicuous looking magnet with you onboard to trip the fuse.

    I said it before and I'll say it again -- any determined engineer will find a way to completely bypass these "security" measures without even straining his/her brain too much.

  • by mbone ( 558574 ) on Monday May 17, 2010 @02:49PM (#32243050)

    The stated dose — about .02 microsieverts, a medical unit of radiation — is averaged over the whole body, members of the UCSF group said in interviews. But they maintain that if the dose is calculated as what gets deposited in the skin, the number would be higher, though how much higher is unclear."

    Well, a quick back-of-the-envelope calculation says it could be a lot. Suppose you model a person as a cylinder 2 meters high by 1/2 meter across. The volume is 0.4 meters^3, the surface area is 3 meters^2. If the skin is 0.1 mm thick, then the volume of the skin is only 0.0003 meters^3, a factor of > 1000 smaller. So a dose of 0.02 microsieverts for the whole body would be 25 microsieverts for the skin.

    If you read the original article, a chest X ray is about 100 microsieverts, but of course that is absorbed in the body, not the skin. Radiation therapy causes skin "burns", but I couldn't find in a quick search the level of radiation absorbed by the skin to make that happen. However, if this is a problem as indicated, then flying one round trip per week (100 flights/year) would mean an exposure of order 2500 microsieverts, or 25 chest X rays, a level I don't think Doctors would be comfortable with.

  • by GameMaster ( 148118 ) on Monday May 17, 2010 @04:36PM (#32245060)

    Don't get rid of them yet, I haven't had time to try any of my ideas out.

    * Using metallic paint to draw a glock 9mm on my skin as if it were in a shoulder holster.

    * Drawing a massive, 1 - 2 foot long, penis down my thigh in metallic paint.

    * (my favorite) Shaving my head bald, drawing a full Terminator style robot endoskeleton on my back, in metallic paint, including the skull on the back of my head and letting my hair grow back enough to cover it before going to the airport.

Houston, Tranquillity Base here. The Eagle has landed. -- Neil Armstrong