Backscatter x-ray machines "tear apart DNA"

[Joe]

This does NOT look good, and adds an much deeper angle to the reasons for the Christmas knicker bomber and the phony WOT (War on Terror) in general. Now who would want our DNA messed with in this way?

Backscatter x-ray machines "tear apart DNA"

Fri Oct 30, 2009 2:26PM EDT

The latest airport security trend is the backscatter x-ray machine, touted as a powerful way to virtually frisk a traveler for contraband without the embarassment of a strip search.

Though touted as completely safe because the level of radiation is so low, travelers have been nervous about the devices -- and not just because it shows off a nice outline of their privates to the people manning the machines -- but because they remain scared of the health problems they might propose.

Looks like a little healthy paranoia might have been a good thing. While the conventional wisdom has held that so-called "terahertz radiation," upon which backscatter x-ray machines are based, is harmless because it doesn't carry enough energy to do cellular or genetic damage, new research suggests that may be completely wrong.

Specifically, researchers have found that terahertz radiation may interfere directly with DNA. Although the force generated is small, the waves have been found to "unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication."

I'm not a doctor, but that just doesn't sound good.

The question now is whether this is or isn't safe. Terahertz waves occur naturally in the environment, and we're hit with them all the time. But should we bombard ourselves with them willingly every time we pass through an airport? No one knows how much terahertz radiation is OK for the body to absorb: Just like sunlight, a little may be fine, while a lot may be deadly. Where does the line get drawn?

Who knows? I, for one, am given a little pause by the news, and hope research continues on before these machines become commonplace.

 

[Ottershrew]

Here's the spin on this from The Transportation Security Administration (TSA) Blog:

This article has been receiving quite a bit of attention and it’s leading people to believe the Backscatter Advanced Imaging Technology (AIT) used by TSA emits terahertz radiation. Recent studies are showing that terahertz radiation may “unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication.”

(I know… who knew that your DNA could be unzipped? Hey buddy, your barn door’s open!!!)

I forwarded the article around to a few subject matter experts here at TSA and was provided with some interesting information:

“TSA has not tested nor procured any terahertz AIT systems.”

That sentence should sum it up for most of our readers, but for those who like to get into the weeds, here is some more interesting information that was given to me from the fine folks at the Office of Security Technology (OST):

The Transportation Security Administration (TSA) has assessed multiple types of AIT systems including X-ray backscatter and millimeter wave. Both offer safe and effective whole body screening for weapons and explosives concealed on a person’s body. Backscatter X-ray technology uses X-rays that penetrate clothing, but not skin, to create an image. Millimeter wave technology uses sensors to collect millimeter wave energy to measure the difference in radiated energy relative to each object against a common background (the human body produces these signatures in typical screening applications) to construct a composite image.

Backscatter - Relies on a narrow, low intensity X-ray beam scanned over the body’s surface at high speed that is reflected back from the body and other objects placed or carried on the body, where it is converted into a computer image of the subject and displayed on a remote monitor. For comparison purposes, the X-ray dose received from the backscatter system is equivalent to the radiation received in two minutes of airplane flight at altitude (0.003* millirem by backscatter (2 scans) compared to .0552 millirem for two minutes of flight). Newer technologies require less scanning time, reducing individual X-ray exposure to .002 millirem for the entire process. The backscatter AIT meets and exceeds the American National Standards Institute (ANSI) standard for personnel security screening systems using X-rays.

Millimeter Wave - Uses non-ionizing radio frequency energy in the millimeter wave spectrum to generate an image based on the energy reflected from the body. The frequency range for millimeter wave technology exists in the range between 30-300 gigahertz. The three-dimensional image of the body is displayed on a remote monitor for analysis. The energy projected by the system is 10,000 times less than a cell phone transmission (.00000597 mW/cm2 for millimeter wave technology compared to 37.5 mW/cm2 for a cellphone).

Other Safety Information

“TSA security screening technologies are required to meet consensus standards, such as those issued by the American National Standards Institute (ANSI), as well as regulatory requirements such as those issued by the Food and Drug Administration (FDA). Our systems are independently tested as well by such laboratories as Johns Hopkins Applied Physics Laboratory (APL) and the National Institute for Standards and Technology (NIST) and FDA. We also apply an aggressive maintenance program to ensure that these systems continue to meet these performance standards. Additionally, TSA Occupational Safety Health and Environment (OSHE) is an active participant in our project integrated project teams. TSA OSHE assists in the development and validation of technology safety requirements. We also conduct safety evaluations as part of our laboratory, TSA Systems Integration Facility (TSIF), operational and site acceptance testing procedures.”

TSA tells its employees, namely Transportation Security Officers (TSOs), about the safety of advanced imaging technology machines, including the radiation exposure, during training on the equipment. In addition, TSA’s Office of Occupational Safety Health and Environment has individuals who work directly with TSOs to communicate safety information about operating the equipment. Information is available to TSOs through the OSHE Web site and employees can contact members of OSHE directly with questions.

*.04 was posted in error. The corrrect number was added. 0.003 millirem. Edited on 1/5/10

Thanks,

Blogger Bob

TSA Blog Team

The joke about the barn door left open seemed a little out of place, imo - but maybe that's just me. I suppose the good folks at the TSA are just trying to come across as, well, human or something.

Edit: spacing

 

[Joe]

The joke about the barn door left open seemed a little out of place, imo - but maybe that's just me. I suppose the good folks at the TSA are just trying to come across as, well, human or something.

Seems to me it was not out of place at all, but a deliberate attempt to belittle and ridicule the idea.

 

[Windmill knight]

This does NOT look good, and adds an much deeper angle to the reasons for the Christmas knicker bomber and the phony WOT (War on Terror) in general. Now who would want our DNA messed with in this way?

This deserves a spot in the hall of fame of evil.

 

[Joe]

This does NOT look good, and adds an much deeper angle to the reasons for the Christmas knicker bomber and the phony WOT (War on Terror) in general. Now who would want our DNA messed with in this way?

This deserves a spot in the hall of fame of evil.

Sure does! And it gives an idea of just what we are up against here! Nasty, tricksy alienses!

 

[Laura]

Are there any religious groups, like Mormons, making a kick about this? I mean, after all, Mormon women wear "the garment" even when having sex!

 

[Laura]

The Physics arXiv Blog


Friday, October 30, 2009
How Terahertz Waves Tear Apart DNA

A new model of the way the THz waves interact with DNA explains how the damage is done and why evidence has been so hard to gather:

Great things are expected of terahertz waves, the radiation that fills the slot in the electromagnetic spectrum between microwaves and the infrared. Terahertz waves pass through non-conducting materials such as clothes , paper, wood and brick and so cameras sensitive to them can peer inside envelopes, into living rooms and "frisk" people at distance.

The way terahertz waves are absorbed and emitted can also be used to determine the chemical composition of a material. And even though they don't travel far inside the body, there is great hope that the waves can be used to spot tumours near the surface of the skin.

With all that potential, it's no wonder that research on terahertz waves has exploded in the last ten years or so.

But what of the health effects of terahertz waves? At first glance, it's easy to dismiss any notion that they can be damaging. Terahertz photons are not energetic enough to break chemical bonds or ionise atoms or molecules, the chief reasons why higher energy photons such as x-rays and UV rays are so bad for us. But could there be another mechanism at work?

The evidence that terahertz radiation damages biological systems is mixed. "Some studies reported significant genetic damage while others, although similar, showed none," say Boian Alexandrov at the Center for Nonlinear Studies at Los Alamos National Laboratory in New Mexico and a few buddies. Now these guys think they know why.

Alexandrov and co have created a model to investigate how THz fields interact with double-stranded DNA and what they've found is remarkable. They say that although the forces generated are tiny, resonant effects allow THz waves to unzip double-stranded DNA, creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication. That's a jaw dropping conclusion.

And it also explains why the evidence has been so hard to garner. Ordinary resonant effects are not powerful enough to do do this kind of damage but nonlinear resonances can. These nonlinear instabilities are much less likely to form which explains why the character of THz genotoxic effects are probabilistic rather than deterministic, say the team.

This should set the cat among the pigeons. Of course, terahertz waves are a natural part of environment, just like visible and infrared light. But a new generation of cameras are set to appear that not only record terahertz waves but also bombard us with them. And if our exposure is set to increase, the question that urgently needs answering is what level of terahertz exposure is safe.

Ref: arxiv.org/abs/0910.5294: DNA Breathing Dynamics in the Presence of a Terahertz Field

 

[Joe]

Are there any religious groups, like Mormons, making a kick about this? I mean, after all, Mormon women wear "the garment" even when having sex!

They certainly won't want to have anything "unzipped" then, let alone their DNA!

 

[anart]

Are there any religious groups, like Mormons, making a kick about this? I mean, after all, Mormon women wear "the garment" even when having sex!

They certainly won't want to have anything "unzipped" then, let alone their DNA!

It's a good point and they have a lot of money to interfere with this if they get riled up about it. So - how to inform the Mormons? Let's let them work FOR normal people for once!

 

[Laura]

Anybody know any good mormon sites to check out and post links to the above or any former mormons who want to express outrage?

 

[Buddy]

This does NOT look good, and adds an much deeper angle to the reasons for the Christmas knicker bomber and the phony WOT (War on Terror) in general. Now who would want our DNA messed with in this way?

This deserves a spot in the hall of fame of evil.

Sure does! And it gives an idea of just what we are up against here! Nasty, tricksy alienses!

I recently read this on SoTT. I can barely put words to what it feels like. Awful!

 

[Brenda86]

This should set the cat among the pigeons. Of course, terahertz waves are a natural part of environment, just like visible and infrared light. But a new generation of cameras are set to appear that not only record terahertz waves but also bombard us with them. And if our exposure is set to increase, the question that urgently needs answering is what level of terahertz exposure is safe.

This is to be filed in the "ugh, that just figures" file. This whole thread is making me sick to my stomach. And that comment about DNA being able to be unzipped and that barn door comment... I mean if this person actually knew about biology (or if they weren't blatantly disregarding any knowledge they might have) they would know it's at the very least possible in theory. Especially considering it's damage to our DNA that seems to cause many forms of cancer.

It's times like this I'm reminded of how glad I am to have come across this site, so that I can actually get this kind of information.

 

[Cyre2067]

Are there any religious groups, like Mormons, making a kick about this? I mean, after all, Mormon women wear "the garment" even when having sex!

Hmm well I was curious so I went over to the church of mormon website and 'chatted live' with a missionary. Here's a transcript of the conversation:

Missionary: Hello

Me: Hi, I had a question about the church's position on these new x ray machines at airports, I dunno if you've heard of them, but apparently they let the security guy see you, well, naked.

Missionary: I haven't heard of them, but the church doesn't have a stance on it.

Me: Oh here's a link if you want to read up on it: _http://tech.yahoo.com/blogs/null/154196

Missionary: OK

Me: Maybe you can clear it up for me, I thought the Mormon church was against nudity in public and other indecencies. Am I mistaken?

Missionary: What do you hope to gain from chatting with me today?

Me: I wanted to learn more about the church and its position on violations of privacy rights.

Missionary: They don't have a stance on it.

Me: That seems odd to me, but thanks for clearing it up.

Missionary: You bet.

I thought it was a bit out of sync for him to have 'not heard' of it, and yet know the church didn't have a position on it. I guess if he didn't hear about it specifically in his church updates (or whatever it is they do) he can safely assume they don't have an official position on it. I also thought it was funny how he sidestepped my question about the church being against nudity in public, I mean, my question was asked in the sincere spirit of curiosity and he thought I came with some sort of agenda. Now THAT spoke volumes about the Church of Mormon imho.

I should have asked about their opinion on mandatory vaccines... though that might of set him off. :P

There's also some chatter over at DU about it. The poster more specifically addresses the christian right and why they aren't all up in arms about the nudie scanners.

_http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=364x2847777

Wow, interesting experience to browse another forum other then this one. Quite a difference! ::likes it here a lot more::

 

[Buddy]

Anybody know any good mormon sites to check out and post links to the above or any former mormons who want to express outrage?

I'll look for some mormon sites, but for the time being, I've got all three related articles up on both my blogs to help spread the word.

 

[Snow]

Since Terahertz wave scanners have the posibility to rip up our DNA (and cause bubbles), what does it do to foreign DNA in our body (like bacteria and virii)? What would happen to all those people who recently got swine flu vaccine shots and who now go through those scanners? Or are their damaged DNA strands then filled by foreign DNA parts that were in those swine flu vaccine shots? (That last one was me thinking outside of the box, sorry for that)