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Cell phone emissions change brain metabolism

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man on cell phone, brain activity metabolism changeCell phones have not been convincingly linked to brain cancer, but that doesn’t mean that their associated radiation has no effect on our bodies. A new study shows that these pervasive devices can alter the brain’s glucose metabolism, a marker of neuronal activity. The findings will be published in the February 23 issue of JAMA, Journal of the American Medical Association.

A team of researchers examined the minute effects of cell phones on the brains of 47 healthy human subjects. The volunteers had a Samsung Knack flip phone secured over each ear for 50 minutes before undergoing PET (positron emission tomography) scans at the Brookhaven National Laboratory in New York. In one 50-minute session, both phones were turned off, but in the other session, the right-ear phone was on and silently receiving a signal.

Nora Volkow, of the National Institutes of Health and co-author of the new study, and her colleagues found that although overall brain glucose metabolism didn’t vary between "on" and "off" assays, "metabolism in the region closest to the antenna was significantly higher [about 7 percent] for on than off conditions." That region includes the orbitofrontal cortex and temporal pole, which are responsible for decision-making and auditory processing, respectively.

The 7 percent increase might actually be on the low end of the spectrum of what people experience after a lengthy phone conversation, Henry Lai, of the Department of Bioengineering at the University of Washington, Seattle, and Lennart Hardell, of the Department of Oncology at the University Hospital, in Örebro, Sweden, noted in an editorial in the same issue of JAMA. Because the phones in the "on" condition in the study were set on mute and only receiving a transmission, they were "actually emitting less radiofrequency radiation than is the case when a user is speaking into a phone, and the effect observed could thus potentially be more pronounced in normal-use situations," they noted.

They also pointed out that it’s unlikely heat from the active phones was to blame for the changes in brain activity.

Although "these results provide evidence that the human brain is sensitive to the effects of [radiofrequency-modulated electromagnetic fields] from acute cell phone exposure," the long-term consequences of this slight shift—if there are any—remain unclear, concluded Volkow and her team. Previous research has even shown a boost in responsiveness during psychological testing after being subjected to cell phone radiation.

Some researchers and concerned individuals still doubt that cell signals are in the clear health-wise, but radiation frequencies, such as UV and x-rays, that are linked to cancer put out much stronger signals than do cell phones. And even though U.S. and European cell phone use has skyrocketed in the past decade, a five-year study published in December 2009 in the Journal of the National Cancer Institute found that rates of brain tumors in the connected countries of Northern Europe remained steady.

In the real world, phones aren’t only planted against our ears, so it’s also possible that radiofrequency emissions "might have effects on other organs leading to unwanted physiological responses," Lai and Hardell noted. Cell phones can generate low frequency electromagnetic fields, the lower frequencies of which have been shown to be "biologically active." 

But just what the impacts of these emissions might be—and how they are manifesting at a cellular level in humans—remain to be seen. Animal and in vitro experiments have shown that radiofrequency-modulated electromagnetic fields exposure can have an effect on cell membrane permeability, cell excitability or neurotransmitters, the researchers noted. Volkow and her colleagues emphatically left cancer out of the equation, concluding that the newfound brain changes "provide no information" about purported "carcinogenic effects" of too much cell chatter.

Image courtesy of iStockphoto/Magaiza

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  1. 1. esmalley 11:31 am 02/23/2011

    This paper is another piece of evidence that EMFs have biochemical effects. There are many open questions about these effects. (I’ve pointed to some other papers here Aside from concerns about cellphones and cancer (or any other potential health consequences), it’s high time for more research on EMFs and biology.

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  2. 2. murraydunn 2:09 pm 02/23/2011

    I’ve seen this same article on several technology websites today, and they all lack the supporting information necessary to judge weather the claimed 7% difference is significant. Was 7% statistically significant? How does 7% compared to variations that might be expected from normal external stimulation such as sunlight, or mental exertion? Since 7% represents the change in a ratio, was the baseline activity level typical of normal wakeful activity? What steps did the researchers take to eliminate other sources of error? How did they evaluate the metabolic rate, was it with a method that has been demonstrated to be accurate.

    I’d like to think that Scientific American holds itself to a high standard of science journalism. However, this article suggests that they are content to just parrot the press releases of other publications.

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  3. 3. ZebulonJoe 6:18 pm 02/23/2011

    There are several energy flow systems in the human body. Acupuncture taps into one of them.
    Ionic flows are influenced by even small changes in the magnetic field surrounding them. The earth’s field of about 1 gauss changes geographically, in both intensity and direction. Being three dimensional, that can produce many and varied effects. Some people are very sensitive to such changes. Modern science has been able to measure them, and use the changes. Mineral prospecting is one case. I live next to a gold mine, and it is not uncommon to see helicopters towing such instruments.
    It is suggested that water dowsers are also sensitive to these changes, hence their ability to find water. Some can even say how much and how deep.
    Studies have linked cancer to nearby high current power lines. Regulations are in place in both USA and New Zealand limiting residential accommodation close to power lines.
    However, much more research is needed to find both personal sensitivity and the effects of alternating current magnetic fields on the human body. I know personally too many people who have had to take precautionary measures against such, to say that their effect is insignificant.

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  4. 4. takensave 4:07 pm 02/24/2011

    Please go to with over 170 studies on cell phone dangers under world news

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  5. 5. takensave 4:08 pm 02/24/2011

    go to, with over 170 studies from around theworld on cell phonedangers under world news

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  6. 6. takensave 4:11 pm 02/24/2011

    I am the editor of the cell phone radiation news bureau with over 170 studies on cell phone dangers posted under world neews- only about 3 of the studies are from the USA-BIG BUSINESS,Any one today who says cell phones andcordless phones aresafe has either done zero research or is receiving funding from the cell phone industry. Children areatthe greatest risk,France has passed a law-if you are under 14 you may not use a cell phone.the UK and other European countries also have age restrictions

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  7. 7. Wayne Williamson 5:51 pm 02/24/2011

    takensave…please post a link to one of these 170 scientific studies(your choice)…thanks…

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  8. 8. clrbear430 9:48 pm 03/2/2011

    The most recent and reliable seeming post by Cecilia Kang of Washington Post at that website (@–Cellphone-industry-attacks-San-Franciscos-ruling-on-radiation.html ) is dated 2010, late June.

    She said "The last major study done by the U.S. cellphone industry was published in 2002. Citing privacy concerns, corporations have declined to release records of heavy cellphone use to match against incidence of brain tumors."

    The World Health Association offers concerning this issue. "Current scientific evidence indicates that exposure to RF fields, such as those emitted by mobile phones and their base stations, is unlikely to induce or promote cancers. Several studies are under way to determine whether the results of some studies on animals have any relevance to cancer in human beings. Recent epidemiological studies have found no convincing evidence of an increased cancer risk or any other disease with mobile phone use." Although the above quote is from 2005.

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