LONDON: Do cell phones cause brain cancer? There's no sign of it, say many. But, if researchers in Europe are to be believed, regular use of a mobile phone over more than a decade raises the risk of brain cancer.

Yes, according to Swedish researchers, who carried out a study, long-term users have double the chance of getting a malignant tumour on the side of the brain where they hold the handset, the 'Daily Mail' reported here today.

And, an hour a day on a mobile phone for over ten years, is be enough to increase the risk. "The international standard employed to protect users from radiation emissions is not safe and needs updating.

"Children should be discouraged from using mobiles because their thinner skulls and developing nervous systems make them especially vulnerable. Adults should exercise caution," lead researcher Professor Lennart Hardell of the University Hospital in Orebro was quoted as saying.

In fact, Professor Hardell and his fellow researcher Professor Kjell Hansson Mild of Umea University came to the conclusion after examining long-term mobile users because cancer can take more than a decade to develop.

After analysing the results of 11 studies carried out around the world, the team found found almost all had discovered an increased risk of cancer of the glial cells that support and protect the nerve cells.

Those who have used their phones for at least a decade are 20 per cent more likely to contract acoustic neuromas and 30 per cent more likely to get malignant gliomas, they said.

There was also an increased risk of acoustic neuromas, benign but often disabling tumours which usually cause deafness, according to the findings published in the latest edition of 'Occupational Environmental Medicine' journal.