Recent
study suggests cell phone users at risk for tumor
October
18, 2004
A Swedish study suggests that people who use a cell phone for at least
10 years might increase their risk of developing a rare benign tumor
along a nerve on the side of the head where they hold the phone.
Anders Ahlbom, a researcher behind the preliminary study, said the results
were surprising and more research is needed.
Several previous studies have investigated whether the use of cell phones
is linked to an increased risk of brain tumors. Although experiments
have shown radiation from mobile phones can affect brain cells in a
lab, more relevant studies on people have found no evidence that the
phones pose a health risk. However, experts have said that because children's
brains are developing, it may not be a good idea for youngsters to use
the phones for long periods.
The three-year study was conducted by by Ahlbom and Maria Feychting,
professor's at the Karolinska Institutet in Stockholm. The study focused
on 750 Swedes who had used the cell phones for at least 10 years. The
results were published in the International Journal of Epidemiology.
In the study, researchers questioned 150 patients already diagnosed
with acoustic neuroma, a benign tumor on the auditory nerve that takes
several years to grow before being diagnosed, and 600 who did not have
it, about their cell phone use.
All 750 subjects had been using cell phones for at least 10 years, nearly
all early analog models that emit more electro-magnetic radiation that
the digital models now on the market. Digital phones emit radiation
in pulses; the older analog varieties emit continuous waves. Since cell
phones increased in popularity in the late 1990's, most of those sold
used digital technology.
The risk of developing a tumor was almost double for those who started
to use phones before their diagnosis. In addition, the tumor risk was
almost four times higher on the side of the head where the phone was
held, Ahlbom and Feychting said.
Retrospective questionnaires are not considered the most accurate method
of determining a link between behavior and disease. Many links that
emerge from such studies turn out not to be true under more rigorous
study.
Acoustic neuroma tumors, which can affect hearing, occur in less tha
one adult per 100,000 people annually.
