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Full-Body Airport Scanners Downsizing For Doctors/Dentists
An anonymous reader writes "Cheap handheld terahertz scanners that do the same thing as those big bulky full-body scanners at the airport could be in your doctor's and dentist's office soon. The Semiconductor Research Corp. has successfully sponsored chip maker Texas Instruments in making cheap CMOS chips that do the same thing as those refrigerator sized full-body scanners at the airport. The resulting handheld versions can be tuned to look inside your teeth in the dentist chair and under you skin at the doctor's office. The best part is that terahertz rays are completely safe, unlike the X-rays used today by dentists and doctors which can cause cancer. Count me in!"
Scanners belong in doctors' offices, not airports.
If I were a dentist, I'd certainly want to know if you're packing heat before I start subjecting you to excruciating pain ;-)
As certified by the $10/hr TSA agent with barely a high school education.
Two of my imaginary friends reproduced once
Yeah we need far more testing on radiation. Especially in the 400nm to 700nm range.
Sure they say its perfectly safe but how long have we been exposing ourselves to it? More data is required!
You are probably familiar with the usual laser safety warning:
Do not look into the laser with your remaining eye.
Obviously light in that wavelength range is problematic.
With the sort of logic that is popular these days we would have rejected fire as unsafe (radiation from a fire is higher frequency than this THz - i.e. very far infrared) and still be eating our food raw in unheated caves.
There is no such thing as "completely safe". The idea is preposterous. It is even more preposterous that we can prove something to be completely safe. Every heartbeat or breath you take is at great risk.
It's all about rational risk assessment and testing. Given the fundamentals here there is no reason to be concerned about the safety of terahertz radiation. It is certainly far safer than the alternatives which have large known risks.
THz radiation may cause DNA resonance:
http://science.slashdot.org/story/09/10/30/1216230/how-terahertz-waves-tear-apart-dna
We need to petition to get these wavelengths banned. These crazy scientists with their fancy lasers that use these dangerous frequencies must be stopped!
It's pretty safe and has been tested over a very long time period. They've even given certain THz frequencies their own names.
440THz is sometimes called "red"
560THz is sometimes called "green"
640THz is sometimes called "blue"
This is slashdot, after all. Most youngsters are already avoiding this harmful radiation by hiding in their mother's basement...
The problem isn't that it involves risk, it is that things that are "completely safe" eventually get abused to the point that they are no longer safe. X-Rays can cause cancer, but we know that x-rays cause cancer and therefore doctors/dentists are more reluctant to use them. Back when X-rays were considered 100% safe, we used them to see how well shoes fit! And other novelties.
Is terahertz radiation safer than x-rays? Quite possibly. If we use terahertz radiation to excess will it be safer than x-rays? Quite possibly not.
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There was never a time when X-Rays were considered completely safe. Roentgen and Thompson both issued warnings regarding overexposure. Within a year of their discovery reports of injuries started appearing.
http://goatrevolution.com/blog2/2006/11/10/radiation-part-cinque-further-uses-and-discoveries-of-x-ray-radiation/
No doctor or dentist I've ever been to was ever 'reluctant' to call for an x-ray. As long as you're insured, it's free money for them to call for an x-ray, whether you need it or not. Last time I went in for neck pain, the doctor actually told me that whatever was causing my pain would most likely only show up on an MRI (as it was most likely due to tissue, not bone, issues), but he wanted to take an x-ray "just to see", and that he'd call for an MRI only if I still had pain a week or two later.
As long as every doctor/dentist has an x-ray machine in-house that they can charge your insurance company for, whether it's really needed or not, they'll use it. If we can replace x-ray with some other most likely less-harmful tech, I'm in.
FWIW, the available research is pretty clear that terahertz radiation poses little or no threat to the body under biological conditions. There's lingering concern that it may have a small ability to affect lipid bilayer permeability (which could imbalance how cells pass messages, receive nutrients, and eliminate waste), but over all, a THz exposure is a lot like being bombarded with visible or infrared light: it will warm you up if left on for too long, but it's not really dangerous on its own. The radiation is too high-frequency to excite any of the electrons orbiting the atoms in the human body (which is how UV causes damage), and much, much too low-energy to knock an electron onto a different atom (which is how X-rays and gamma radiation cause damage.) Any effects it does have must be extremely subtle—and the body is very good at handling subtle problems, since we replace almost every cell every ten years on average.
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
It's pretty safe and has been tested over a very long time period. They've even given certain THz frequencies their own names.
440THz is sometimes called "red"
560THz is sometimes called "green"
640THz is sometimes called "blue"
And they stopped there because 640 THz should be enough for everybody.
You are not taking into account, that doctors are wary of using MRI devices for scheduling and expense reasons. An X-ray image from a leased dental device is almost free (less than a hundred euros for private institutions here) and takes mere minutes, while an MRI scan costs thousands of euros and may take hours.
Also, since MRI is more useful in a wider variety of situations, someone else probably needs it more or needs it sooner - you might end up having a huge waiting time to get yourself scanned. It is prudent to take the x-ray, because if the doctor can see the ailment there, the MRI scan may not be needed at all. He will also send you out, because if the pain disappears in a couple of weeks, the MRI won't be necessary. Money, time, work, and possibly lives, might be spared.
If you are worried about the risks of a single x-ray, I assure you that they are beyond neglible - especially if you compare that risk with the possible wasted utility of an MRI device.
The dentist will allow you to opt out, in favour for a traditional cavity search.
"The radiation is too high-frequency to excite any of the electrons orbiting the atoms in the human body (which is how UV causes damage)"
You meant too LOW frequency , as terahertz is about order of magnitude of micrometer of wavelength : it is in the infrared part of the spectra (far or near depending on how many THz we are speaking of). In fact frequency is going from very low (VHF->FIF->NIF->Visible) to very high (Blue->UV->X->Gamma). Higher frequency=High energy is bad as it can easily knock electron off orbits. Low Frequency=Low Energy less dangerous, to even inactive on our body. Which is the invert with wavelength (short wave =very dangerous , very long wave think radio BHV etc harmless). Then there is also the question of quantity, but as a rule of thumb it is enough.
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