I published a story yesterday about the NYPD, and the Department of Defense, using new body scanners to conduct “virtual frisks” on the citizens of New York using Terahertz Imaging Detection. These new scanners use terahertz waves to detect if someone may be carrying a weapon. MIT published information that shows these waves can tear apart DNA.
From Technology Review:
…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.
[...] From Scotty Starnes’ Blog: [...]
dooh those are just cameras your body emits tons of the stuff. Its a form of heat. Look it up!
Think I’ll stick with the MIT scientist who conducted actual studies.
While your loyalty to scientists (if genuine) is admirable Scotty, it wasn’t an “MIT scientist who conducted actual studies”; in fact, it was a scientist and his group at Los Alamos, and what they did was to conduct computer simulations using a model (not that I’m against simulations or models, not at all) — and not to collect actual empirical evidence. In such a situation, it’s always important to examine the assumptions and constraints underlying said model.
Libertarians are all abuzz with this study because of their bias against the NYPD’s goal of using this technology, but, it is not reflecting the truth.
THz waves *directly* interacting with DNA *might* cause the effects that this scientist modeled; however, that would not happen in real life. (Do you wear your DNA on your sleeve?
In fact, further actual investigation by another group showed that while the DNA unzipping “breather” modes can take place in the scenario outlined by that model, with just a few reasonable physical conditions added, this does not occur at all, and thermal effects are far greater:
http://arxiv.org/abs/1012.4153
(Should you be interested in the real truth, then it’s worthwhile for you to check it out.)
As the commenter above you pointed out (unfortunately somewhat ineloquently, though that shouldn’t really matter), these is a type of radiation that your body already naturally produces; if damage were going to occur, that would be the likely culprit. And, as some large portion of what is considered “THz Waves” is in fact part of the Far IR portion of the EM spectrum, they are indeed a “form of heat”.
So, not proven dangerous.
But in any case, passive measurement is never a threat.