LONDON (Reuters) - Using a mobile phone may increase the risk of certain
types of brain cancer in humans and consumers should consider ways of
reducing their exposure, World Health Organisation (WHO) cancer experts said
on Tuesday.
A working group of 31 scientists from 14 countries meeting at the WHO's
International Agency for Research on Cancer (IARC) said a review of all the
available scientific evidence suggested cell phone use should be classified
as "possibly carcinogenic".
The classification could prompt the U.N. health body to look again at its
guidelines on mobile phones, the IARC scientists said, but more research is
needed before a more definitive answer on any link can be given.
The WHO had previously said there was no established evidence for a link
between cell phone use and cancer.
"After reviewing essentially all the evidence that is relevant ... the
working group classified radiofrequency electromagnetic fields as possibly
carcinogenic to humans," Jonathan Samet, chair of the IARC group, said in a
telebriefing.
He said some evidence suggested a link between an increased risk for
'glioma', a type of brain cancer, and mobile phone use.
The decision comes after a study published last year which looked at almost
13,000 cell phone users over 10 years found no clear answer on whether the
mobile devices cause brain tumours.
The decision has been keenly awaited by mobile phone companies and by
campaign groups who have raised concerns about whether cell phones might be
harmful to health.
Use of cell phones use has increased dramatically since their introduction
in the early-to-mid 1980s. About 5 billion mobile phones are currently in
use worldwide.
(Reporting by Kate Kelland, editing by Alison Williams)
Read VIDEO EXPLAINER
By Elizabeth Cohen
CNN Medical Correspondent
ATLANTA, Georgia (CNN) -- "I hope you're talking to me on a speakerphone,"
Devra Davis barks at me when I call her on my cell phone. "You'd better not
be holding that phone up to your head."
Cell phones do emit radiation. No one knows definitively whether it's enough
to worry about.
1 of 2 Indeed, I'm not. This is a good thing, because you don't want to get
into an argument with Davis on this subject. She's the director of the
University of Pittsburgh's Center for Environmental Oncology, and her group
recently put out recommendations that we should be using a speakerphone or
ear piece.
The report says children, who have thinner skulls and developing brains,
should use cell phones only in case of emergency.
And heaven forbid anyone should carry a cell phone in a pocket or clipped to
a belt. "You're just roasting your bone marrow," Davis said.
Oh, boy. Another thing to worry about. Or maybe Davis is an alarmist. It's
so hard to tell. Although there are many large studies showing no connection
between mobile phones and cancer, there are a few that do. As Davis puts it,
do you really want to play Russian roulette with your head? Explainer:
Radiation fields and the brain >
But if you do buy the cellphones-cause-cancer argument, you have to figure
out the best way to talk on a cell phone, seeing as how most of us can't
live without them. Should you use the wired headset that came with your
phone? A Bluetooth earpiece?: Does your kid have a cell phone?
Cancer expert warns staff on cell phone use
I embarked on a journey this past week to answer these questions and at many
points have been very sorry I did. This is the mother of all "the jury is
still out" issues.
Cell phones have been wildly popular for only a matter of years, and it can
take at least a decade for cancers to show up. Studies contradict each
other, and scientists bicker: Some will tell you with great conviction that
there's nothing to worry about. Others will tell you with equal conviction
that an epidemic of brain tumors may be just around the corner.
The cell phone industry itself says "the overwhelming majority of studies
that have been published in scientific journals around the globe show that
wireless phones do not pose a health risk." You can watch the experts go at
it on "Larry King Live" > this week.
So what are we all to do until they figure it out? After enough interviews
with physicists, engineers and doctors to make me want to stick my head in a
microwave oven, one common line of reasoning emerged.
Cell phones do emit radiation.
No one knows definitively whether it's enough to worry about. Mobile phones
meet federal safety limits, but if you're still worried, there are some
simple steps you can take to lower your exposure to radiation. Watch more on
limiting your risk >
1. Use the speakerphone
This was, without question, the favorite alternative of the experts I talked
to. Nothing is near your head. "Hold it away from a minimum of a few inches.
A foot or two is ideal," said Magda Havas, an associate professor with the
Institute for Health Studies at Trent University in Ontario, Canada.
Havas gives me a little math lesson. Every inch you can get away from your
body, the radiation reduces very quickly. "Hold it out two inches, and the
radiation drops by a factor of four. Hold it out four inches, and it drops
by a factor of 16," she says.
In other words, said Louis Slesin, editor of Microwave News, "every
millimeter counts."
2. Use a wired headset with a ferrite bead
No, this is not a piece of jewelry. A ferrite bead is a clip you put on the
wire of a headset. The concern is that the wire itself emits radiation into
your ear. The bead is designed to absorb the radiation so you don't. They're
inexpensive and available at stores or online.
These clips are a favorite of Slesin's. "It's the way to go," he said.
Another fan: Lawrie Challis, physicist and former chair of the Mobile
Telecommunications and Health Research Programme, a government panel in
Britain. "They did tests at the University of York and found that under even
the worst conditions, if you use a ferrite bead, you can't even measure the
radiation coming off the wire. This common device kills the radiation."
Of course, if the phone is in your pocket or clipped to your belt, all bets
are off, because the phone itself will be radiating into your body. So if
you're worried about radiation, keep the phone as far away as possible, and
Challis adds to do your best to make sure the wire isn't touching your body.
3. Use a Bluetooth earpiece
A Bluetooth earpiece still has radiation, but it's at least 100 times less
than the radiation you get when you hold a cell phone to your head, Havas
says.
Our experts were split on which was better: a Bluetooth headset or a wired
one. Israeli government recommendations issued this week specifically
suggest a wire; Havas likes the Bluetooth. But even she says not to wear it
when you're not talking; it still sends out a signal.
"Bluetooth is only whispering radiation into your ear. The problem is, some
people wear it all the time," she says. "At the very least, switch it from
ear to ear so you don't have too much exposure on one side."
Michael Foley, Ph.D., executive director of the Bluetooth Special Interest
Group, says Bluetooth earpieces radiate 200 times less energy than cell
phones. "There is no evidence that a Bluetooth headset has any adverse
effects on its users," he said.
4. Use a "hollow tube" earpiece
It's just like a regular wired earpiece, except the last six inches or so --
the part next to your ear -- is a hollow tube. There's no wire under the
plastic.
Health Library
MayoClinic.com: Health Library
"You're getting the sound through the air. You're not dependent on
radiofrequency waves," said Dr. David Carpenter, director of the Institute
for Health and the Environment at the University of Albany.
Hollow tube earpieces can be purchased on several Web sites.
5. Get a phone with less radiation
Phone radiation is measured in specific absorption rate, or SAR. To look up
the SAR for your phone, check this list on CNET.com.
You might think the experts mentioned above all use earpieces or a
speakerphone. Not so. Several said they hold it right up to their heads
because they use their cells so infrequently, they're not worried about
radiation.
"I use it maybe once or twice a week, no more than 10 minutes," said
Challis, the former head of the British committee that studied cell phones
and radiation. "I use a land line whenever I can."
It's the exposure, day after day, year after year, that matters. As Challis,
who's retired, puts it, "If I were younger, I'd take this much more
seriously."
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