Assessing the effects of cell phone radiation on brain tissue

by Sunanda Creagh

Researchers have found a novel, non-invasive technique for measuring brain hot spots caused by electromagnetic radiation from mobile phones, according to a study published today.

However, the scientists noted their model measured a "worst case scenario" level of heat and that in reality, the body's natural self-cooling mechanisms would reduce the amount of heat rise in the brain caused by a mobile phone.

The 's cancer agency, the International Agency for Research on Cancer (IARC), classed mobile phones as Group 2B or "possibly carcinogenic" in a report released last year. That puts them in the same IARC category as coffee, napthalene and pickled vegetables.

To test how much electromagnetic energy from was absorbed into a brain, US researchers David H. Gultekin and Lothar Moeller used (NMR) techniques on a brain that had been removed from a cow.

The scientists rigged up an to help create 3D images of the hot spots without allowing the strong magnetic fields of the NMR to interfere with the results.

The results were checked against heat measurements taken with fibre optic and showed that the NMR method delivered accurate findings.

The researchers concluded that "NMR thermometry offers sufficient spatial and temporal resolution to characterise the hot spots from absorbed cell phone radiation in… ."

However, the researchers said that a biological process called perfusion—in which blood is directed to overheated body parts to help cool them down—would mean that the amount of heat rise caused by a mobile phone in a living brain would be less in real life than what was studied in this experiment.

"This study essentially presents the in terms of radiation-heated brain tissue. The temperature rise in the in vivo is expected to be smaller because of perfusion," the study said.

The study was published in the journal Proceedings of the National Academy of Sciences.

Their technique was an improvement on existing methods to test for hot spots, which currently involve inserting a probe into a gel designed to mimic the way a brain would conduct heat.

"They are invasive and they can not measure the thermal fields in ex-vivo or in-vivo tissues. NMR method is non-invasive and can measure the thermal fields in ex-vivo and in-vivo including the perfusion effects," said one of the scientists who conducted the research, Dr David Gultekin from the Memorial Sloan-Kettering Cancer Centre in New York.

Another author of the paper, Dr Lothar Moeller of Bell Labs, said "our method has the advantages that it can be applied to measure remotely temperature enhancement caused by cell phone radiation inside in-vivo brain. No other existing method can do this."

Professor Rodney Croft, Professor of Health Physiology at the University of Wollongong and a researcher of mobile phone radiation said the research was interesting proof-of-concept study but "I don't think it has much relevance to the mobile phone debate."

"What they are talking about at the moment is a non-realistic model using biological material without thermoregulation," meaning natural mechanisms that help cool down overheated body parts, said Dr Croft.

"We can be exposed to quite a lot of changes in temperature and our body can deal with it. If we get mobile phone exposure, because it's such a small amount of heat, the thermoregulation can deal with that without any difficulty."

Dr Croft said there still was no research suggesting major health problems caused by use.

"It really doesn't represent much of a risk. We are talking about a conclusion that it remains a possibility [that they may cause cancer] but there is no evidence it is a problem."

More information: "NMR imaging of cell phone radiation absorption in brain tissue," by David H. Gultekin and Lothar Moeller: www.pnas.org/content/early/2012/12/10/1205598109

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Grallen
1 / 5 (3) Dec 18, 2012
Enough heat that they need to state that in living tissue that less would build up? Because in dead tissue get's alarmingly warm?

I thought the amount of energy absorbed by biological tissue was supposed to be negligible?

If it's absorbing that much energy what's to say there isn't enough to knock an electron loose and causes a free radical in the wrong place?

I'm not exactly an expert here, so... am I worrying needlessly?
cantdrive85
2.3 / 5 (3) Dec 18, 2012
There is a wired hands-free device in every new phone sold for a reason. Cell phone manufacturers learned a great deal from tobacco litigation and if it becomes a health issue their legal defense is already in place. If you didn't use the included "safety" device, that was your choice.
FMM
1 / 5 (1) Dec 18, 2012
It is astonishing that people's first thought is lawsuits.
cantdrive85
3 / 5 (4) Dec 18, 2012
You must not be from the United States for Lawyers, the Land of the Hundreds of Thousand laws.
elektron
1 / 5 (1) Dec 18, 2012
considering the average human life span was 10 years for the first 200,000 years, and then 45 years during the middle ages, we have to expect a little bit of harm from our technology considering the average life span is now over 70.
caska
5 / 5 (1) Dec 18, 2012
Enough heat that they need to state that in living tissue that less would build up? Because in dead tissue get's alarmingly warm?

I thought the amount of energy absorbed by biological tissue was supposed to be negligible?

If it's absorbing that much energy what's to say there isn't enough to knock an electron loose and causes a free radical in the wrong place?

I'm not exactly an expert here, so... am I worrying needlessly?


Your cells have their own defence mechanisms to reduce free radicals. And free radicals aren't all too alarming in the first place and considering they're caused naturally in metabolic reactions as well as mere sun exposure. Hence there might be a slight elevation in probabilities of damage in this form but it's really quite unlikely.
Sonhouse
1 / 5 (2) Dec 18, 2012
considering the average human life span was 10 years for the first 200,000 years, and then 45 years during the middle ages, we have to expect a little bit of harm from our technology considering the average life span is now over 70.

A cell phone puts out about 1/10th of a watt or so but the effects on the body are accumulative so 1 watt for 1 second produces the same heat as 1/10th of a watt for 10 seconds and so forth.

It depends mainly on how close you hold the phone to your ear and how long you talk as to how much damage is done.

Personally, I put the thing on speakerphone and just hold it in my hand or on a desk and pretty much eliminate any problem with my body.

On the other hand, if you visit an airport, you are going to be bombarded with RF from many different sources from WIFI to communications to radar, all adding up to heat the body, the whole body in this case. Radar is pulsed and upwards of a megawatt pulse power so that can be significant in long term.
j_stroy
5 / 5 (1) Dec 18, 2012
Its a biological system so perfusion is just one of the factors... Blood has many things in it. I recall a Norwegian rat study where they found that low levels of cell phone radiation caused a dilation in the blood brain barrier which in turn allowed albumin proteins present in the blood to cross it and enter the brain tissue & react there, causing much larger physical damage than the radiation on its on. Questions about damage from radiation aren't the be all and end all. Isolation doesn't really work in a complex biological system.
Gino
1 / 5 (1) Dec 18, 2012
Is this bandwagon of research into the supposed cancer risk of mobile phones never to end it reminds the of the Pill nonsense sponsored by the condom manufactures

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