The largest study to date on the potential health effects of
mobile phone use concludes that the devices do not increase the
risk of brain cancer among average cell phone users. But it
finds a slightly greater risk of cancer among heavy users.
The massive international research project, conducted by the World
Health Organization's Interphone Study Group, surveyed more than
13,000 mobile phone users in 13 countries over the past
decade. Overall, members of the panel concluded that
radio-frequency energy emitted by mobile phones does not increase
the risk of the two main types of brain tumors, glioma and
meningioma.
However, when researchers looked at the 10 percent of subjects who
identified themselves as heavy users, they found a 40 percent
increased risk of glioma. Heavy users included those who
talked on a mobile phone for at least a-half hour a day, seven days
a week, for ten years.
But panel member Daniel Kewski, of the Center for Population Health
Risk Assessment at the University of Ottawa in Canada, says the
group was unable to prove that heavy mobile phone use increased the
risk of cancer because the findings were based on the sketchy
memories of some participants.
"If we asked you to be a participant, we would sit down with you
and ask you to try and remember every cell phone that you had used
in your entire life," said Daniel Kewski. "And then we would ask
you how many times a day you made phone calls, and how long you
were on the phone for each of those calls on average. So your
recall of your cell phone utilization patterns may not be
perfect."
Kewski says the remaining 90 percent of mobile phone users were on
the device an average of two to two-and-a-half hours per
month.
Otis Brawley, chief medical and scientific officer of the American
Cancer Society, says there is little evidence that even heavy cell
phone use causes a significant increase in brain cancer. And
if it did, says Brawley, the problem would be dwarfed by other more
serious public health concerns:
"If you use the worst case studies that we have to date, it's about
300 additional brain tumors per year in the United States," said
Otis Brawley. "Compare that with the fact that we have definite
data to show that 3,000 deaths are caused by auto accidents due to
cell phones in the United States every year."
Panel member Jack Siemiatycki, a professor of environmental
epidemiology at the University of Montreal agrees, saying there is
no reason for unnecessary panic or concern among average cell phone
users.
"For people who are heavy duty users, who really do use 1,000
minutes a month or 2,000 minutes a month, or something like that,
then you are getting into a zone where we may have seen a risk,"
said Jack Siemiatycki.
In that case, Siemiatycki says, users should consider operating
their mobile phones without holding them to their ears by using
wired earplugs or by using a wireless Bluetooth device, which emits
less radio frequency energy than the mobile phone's
electronics.
Christopher Wild is director for the International Agency for
Research on Cancer based in Geneva:
Wild says the Interphone Study Group will convene a meeting next
year to review data from all studies that have been conducted
looking at cell phone use to see whether the devices increase the
risk of brain cancer among heavy users.
"We need to look in more depth at that finding in the context of
all the other information that's available to us before we are
confident to conclude that there's no associated risk," said
Christopher Wild.
The paper by the Interphone Study Group on mobile phone use and the
risk of brain cancer was published in the International Journal
of Epidemiology.
Source:
http://www1.voanews.com/english/news/health/Study-Finds-Small-Increase-in-Brain-Cancer-with-Excessive-Mobile-Phone-Use-94213969.html