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Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

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Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#21

Post by aphyr »

zbanks wrote: post #4

More tellingly, on an average two-hour flight, you'd receive about 100 times the radiation from a single scan. But, by using the transitive property, you're more likely to die from radiation at flying altitudes than from a terrorist attack on said airplane. EDIT: Sorry, I forgot to include the link: http://en.wikipedia.org/wiki/Backscatter_X-ray#Health_effect... Which comes from: http://hyperphysics.phy-astr.gsu.edu/…

This comparison is meaningless.

The risk of cancer is caused by DNA errors. Your cells are constantly checking and repairing your DNA for mutations and damage. They can usually repair or detect a low error rate, like the kind you get from living at high altitude, in a house with a minor radon source, or flying on a plane. What they can't deal with as well is a sudden burst of many errors. Backscatter X-ray scanners deliver their entire dose to a tissue region in a few microseconds. That's the kind of exposure we're talking about, and it has an entirely different biological impact.

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#22

Post by stretchwithme »

Yes, but the peace of mind one experiences while being groped or ionized makes it all worth while.

Regarding how much radiation you receive on the plane itself, I always try to sit away from the window and on the north side of the plane if possible.

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#24

Post by tibbon »

goldenthunder wrote: post #17

Maybe I suck at basic prob/stats but if you remove the scanners, I bet the chance of a plane getting blown up by a terrorist is significantly increased. ;)

Two things have made the US safer

1- Pilots with guns & keeping the doors closed for the full flight

2- Passengers not willing to allow others on the plane do harm to the plane. If passengers see things happen now, they will stand up and makes attempts to stop them. We won't have a 9/11 style hijacking. Even if someone gets a box cutter in, people will take them down before they'll let them take the plane.

I can't imagine how these body scanners would make us significantly safer.

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#25

Post by daten »

naz wrote: post #19
maninthemirror wrote: post #13

Earlier quoted context omitted.

You are understating the risk from backscatter radiation. Because the radiation is sent in a burst, and targets skin tissue, the DNA damage may be far greater than a similar dose of cosmic radiation. You are also assuming that the backscatter machines are functioning properly and aren't overdosing people.

A single backscatter X-ray scan gives a radiation dose of 0.009 mrems, about the same as eating a banana. http://en.wikipedia.org/wiki/Banana_equivalent_dose Don't get me wrong, I'm opposed to the scanners as much as anyone for privacy reasons and general pointlessness. But I'm seeing a lot of bad science thrown around here.

You're not comparing bananas to bananas.

As I understand, the limited information that has been publicly released about the backscatter machines is a useless measurement when you take into account how they actually work. You can't apply a standard measurement from a medical x-ray machine that targets a small part of your body using one technique to a different machine that targets your entire body using a different technique.

So the two problems are:

1. You don't have good numbers to even evaluate how dangerous they are, many evaluations, including possibly the article above, are useless because they don't have the real data to compare to.

2. The radiation exposure from a banana also effects your body differently than a medical x-ray machine which is in turn different from a backscatter machine targeting your entire body.

I'm not saying people aren't trying to evaluate the actual risk in good faith. I'm saying they're skipping the step where we get useful numbers from the manufacturer of the machine to even apply good science to.

Edit: by "whole body" I mean "whole surface of your body" since it's concentrated on your skin

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#26

Post by travisp »

naz wrote: post #19
maninthemirror wrote: post #13

Earlier quoted context omitted.

You are understating the risk from backscatter radiation. Because the radiation is sent in a burst, and targets skin tissue, the DNA damage may be far greater than a similar dose of cosmic radiation. You are also assuming that the backscatter machines are functioning properly and aren't overdosing people.

A single backscatter X-ray scan gives a radiation dose of 0.009 mrems, about the same as eating a banana. http://en.wikipedia.org/wiki/Banana_equivalent_dose Don't get me wrong, I'm opposed to the scanners as much as anyone for privacy reasons and general pointlessness. But I'm seeing a lot of bad science thrown around here.

While I might agree that the worried about an X-ray scan are overblown (I assume that is your position), that number is looking at a whole body number. Part of the argument is that the amount may be significantly higher because the dose is concentrated near the surface of the skin, rather than across the whole body like cosmic ray and chest X-ray exposure.

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#28

Post by butterfi »

With all due respect to Dr. Reiz, and the Dept. of Physics at ASU, I think I'll be taking my advice from the group of doctors from UCSF (a school well known and respected for its medical research) who wrote a formal letter to the president's science advisor. The letter is worth reading.

"Agard and several of his UCSF colleagues recently wrote a letter to John Holdren the president's science adviser, asking for a more thorough look at the risks of exposing all those airline passengers to X-rays. The other signers are John Sedat, a molecular biologist and the group's leader; Marc Shuman, a cancer specialist; and Robert Stroud, a biochemist and biophysicist."

Story here: http://www.npr.org/templates/story/story.php?storyId=1268330...

Letter here: http://www.npr.org/assets/news/2010/05/17/concern.pdf

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#29

Post by shasta »

burgerbrain wrote: post #9
wnoise wrote: post #2

Oh, well if they're equal, then that means this is a perfectly proportional and appropriate response.

That only holds if being sexually molested and having naked pictures of yourself taken is weighted at zero. Furthermore, this statistic in no way indicates that these screenings reduce the risk of dying in a terrorist attack. 1 plus 1 does not equal 0. You've allegedly doubled your risk of dying, not reduced it.

Well, you're right to question what the reduction in risk these scanners produce, but your first point is way off. The cost of terrorist attacks is hardly limited to death. Those planes and buildings aren't free. Not that cancer treatments are, either, but if you weigh in the psychological damage to the public (you know, why they call it "terrorism"), terrorist attacks are far more costly.

Re: Chance of Dying From Backscatter Radiation Same as Chance of Terrorism

#30

Post by burgerbrain »

shasta wrote: post #29
burgerbrain wrote: post #9

Earlier quoted context omitted.

That only holds if being sexually molested and having naked pictures of yourself taken is weighted at zero. Furthermore, this statistic in no way indicates that these screenings reduce the risk of dying in a terrorist attack. 1 plus 1 does not equal 0. You've allegedly doubled your risk of dying, not reduced it.

Well, you're right to question what the reduction in risk these scanners produce, but your first point is way off. The cost of terrorist attacks is hardly limited to death. Those planes and buildings aren't free. Not that cancer treatments are, either, but if you weigh in the psychological damage to the public (you know, why they call it "terrorism"), terrorist attacks are far more costly.

The real cost of terrorism is having to deal with all the people talking about "the real cost of terrorism", and instituting retarded policies like these scanners/molestation sessions.

Planes and buildings are cheap as shit in comparison.

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