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A new way to measure mobile phone ‘hot spots’ in the brain

Researchers have found a novel, non-invasive technique for measuring brain hot spots caused by electromagnetic radiation…

The researchers used nuclear magnetic resonance imaging to identify the effects of mobile phone radiation on the brain.

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 World Health Organisation’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 cell phone radiation was absorbed into a brain, US researchers David H. Gultekin and Lothar Moeller used nuclear magnetic resonance (NMR) techniques on a brain that had been removed from a cow.

The scientists rigged up an antenna system 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 temperature sensors 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… biological tissues.”

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 worst case scenario in terms of radiation-heated brain tissue. The temperature rise in the in vivo brain tissue 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 mobile phone 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.”

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8 Comments sorted by

  1. Joel Moskowitz

    logged in via Facebook

    This study is irrelevant to the controversy about cell phone radiation health effects.

    Almost all of the hundreds, if not thousands, of studies that have found biologic activity due to cell phone radiation exposure, have involved sub-thermal amounts of radiation. Also, the human epidemiologic research which has found increased tumor risk associated with long-term cell phone use involved cell phones that emit radiation at sub-thermal levels.

    Dr. Croft is a denialist. There is a considerable…

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    1. Mike Cowley

      logged in via Facebook

      In reply to Joel Moskowitz

      And you think linking to the Huffington Post and a repository of press releases is going to convince anyone? The HuffPo interview with a man who recommends as a source of quality information?

    2. Sue Ieraci

      Public hospital clinician

      In reply to Joel Moskowitz

      Dr Moskowitz, you own study concluded this: "The current study found that there is possible evidence linking mobile phone use to an increased risk of tumors from a meta-analysis of low-biased case-control studies. Prospective cohort studies providing a higher level of evidence are needed."

      Hardly strong enough evidence on which to accuse others of denialism.

  2. Yoron Hamber


    Still think it will be statistics that will show us, one way or another, although it will be tricky. This sound as someone measuring heat on/in a dead brain, don't know what that have to do with reality. And then we have all that wireless stuff too. You can't say that radiation is negligible.

  3. Comment removed by moderator.

  4. Geoff Taylor


    Dr Croft, I am not sure I would describe acoustic neuroma and astrocytoma as not serious. The Hardell studies found the risk ratio was 5:1 for those who had commenced mobile phone use before age 20. Also the effect was ipsilateral, ie. it occurred on the side of the head used to listen to the phone.

    1. Sue Ieraci

      Public hospital clinician

      In reply to Geoff Taylor

      Hardell's work as a meta-analysis, including one meta-analysis in the group of studies. This is itself is methdologically poor. To quote the paper: "The cohort study was of limited value due to methodological shortcomings in the study. Of the 16 case-control studies, 11 gave results for > or =10 years' use or latency period. Most of these results were based on low numbers. An association with acoustic neuroma was found in four studies in the group with at least 10 years' use of a mobile phone. No…

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  5. Sue Ieraci

    Public hospital clinician

    Mobile phone use is but one of many sources of EMR in our modern society - along with the sun, computers, power lines, microwave ovens, baby moniotors...any many more. Many of these appliances add to quality - and indeed safety - of modern life.

    To many impoverished communities in developing countries (as illustrated above), mobile telecommunications have created a huge advantage in the ability to communicate and access help - in potentially life-saving situations. Similarly, mobile phones have…

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