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

kfc 10/30/2009

• 73 Comments

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

Source: http://www.technologyreview.com

Cosa dice l'articolo sopra pubblicato:

Secondo il dottor Boian Alexandrov del National Laboratory di Los Alamos nel New Mexico, onde terahertz o terahertz (THz) distruggono il DNA umano. Le onde rompono il filo dell’elica del DNA Umano. Ora un team di tecnici della University of Texas di Dallas, hanno in programma di adottare i chip che emettono THz-wave nei telefoni cellulari per l’uso quotidiano, come un sistema di imaging per i consumatori, per la polizia e il personale medico. Questa tecnologia potrebbe però uccidere o far ammalare milioni di persone. La controversa tecnologia di scansione THz usata dal TSA in molti aeroporti degli Stati Uniti sta per essere adottata per l’uso dei telefoni cellulari. Studi sulle radiazioni terahertz hanno causato allarmismo tra gli esperti e sollevare allarme circa i rischi significativi per la salute negli esseri umani. Recentemente alcune grandi holding della comunicazione, hanno promosso un nuovo chip che permette l’adattamento di un dispositivo di nuova generazione di onde THz da integrare sui telefoni cellulari.

La squadra di fisici del National Laboratory di Los Alamos, ha trovato la cosa spaventosa, perchè l’esposizione alla radiazione THz è cumulativa e colpisce il tessuto del DNA umano e animale. I rapporti scientifici da Los Alamos, dichiarano che le dinamiche di respirazione del DNA in presenza di un campo terahertz rivela una situazione molto preoccupante – anche la prova scioccante che la radiazione THz significativamente può danneggiare il DNA delle persone che vengono esposte direttamente, come ad esempio tutte quelle che vengono sottoposte attraverso gli scanner aeroportuali e tutti i lavoratori e operatori che si trovano accanto alle macchine.