NicFleming

Friday, January 26, 2007

Long-term mobile-phone users are significantly more likely to develop a certain type of brain tumor on the side of the head where they hold their handsets, according to new research from Finland.

A large-scale study there found that those who had regularly used mobiles for longer than 10 years were almost 40 percent more likely to develop nervous system tumors called gliomas near to where they hold their phones.

Gliomas are tumors that develop in glial cells - tissue that provides energy, nutrients and other support for nerve cells in the brain.

The finding, to be published later this year in the International Journal of Cancer, is the second study to suggest increased risks of specific types of brain tumors in regions close to where mobile phone emissions enter the head.

But a number of other studies have found no increased health risks associated with mobile- phone use, and some industry figures have declared that no more research is needed.

Researchers from the Radiation and Nuclear Safety Authority in Finland compared the mobile phone use of 1,521 people with gliomas with that of 3,301 people without the cancers.

Before separating out long-term users or looking at the different risks of developing tumors on the side where users held the phone, the scientists found no link between mobile use and gliomas.

When they looked only at people who had used a mobile for 10 years or more, however, they found that they were 39 percent more likely than average to get a glioma on the side of their head where they held their handset.

Anssi Auvinen, an epidemiologist involved in the study, said: "It seems credible as it was after long-term exposure - which makes sense in terms of the length of time it takes for tumors to develop - and it is localized to the side of the head where the handset is held. We need more research on long-term use."

Louis Slesin, editor of Microwave News, a US newsletter on radiation and health that reported the new study, said: "We now have two tumor types found among people who use mobiles for more than 10 years, shown by two different research groups. That is compelling evidence."

But Anthony Swerdlow of the British-based Institute of Cancer Research, who was also involved in the study, said the results should be treated cautiously. "People who have had a cancer tend to look for reasons for their cancer," he noted.

"This might influence their report of the side of the head on which they used their phone."

Lawrie Challis, chairman of the British government-funded Mobile Telecommunications Health Research program, said most research had shown that mobiles were safe in the short term but there was a "hint of something" for longer-term users.

He is negotiating funding for a long-term international study into whether 200,000 volunteers face increased risks of any serious diseases including cancer as a result of using a mobile. The finding from Finland, he said, is "further reason why a long-term study is something that we need to do." THE DAILY TELEGRAPH