Using mobile phones for more than 10 years 'doubles risk of brain cancer'

Researchers found that long-term users had double the chance of getting a malignant tumour on the side of the brain where they held the handset.

An hour a day on a mobile phone is thought to be enough to increase the risk.

The Swedish scientists said the international standard employed to protect users from radiation emissions was not safe and needed updating.

They said children should be discouraged from using mobiles because their thinner skulls and developing nervous systems made them especially vulnerable. Adults should exercise caution.

The study examined long-term users because cancer can take more than a decade to develop.

Its authors, Professor Lennart Hardell of the University Hospital in Orebro and Professor Kjell Hansson Mild of Umea University, analysed the results of 11 studies carried out around the world.

They found almost all had discovered an increased risk of cancer-of the glial cells that support and protect the nerve cells.

There was also an increased risk of acoustic neuromas - benign but often disabling tumours which usually cause deafness.

The Swedish analysis revealed that 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.

The risk is even greater on the side of the head the handset is held: long-term users were twice as likely to get the gliomas and two and a half times more likely to get the acoustic neuromas there than other people.

The industry denies there is any proven risk to health associated with the devices.

The Mobile Operators Association said: "This is not new data for the World Health Organisation and the many independent expert scientific committees who state that there are no established health risks from using mobile phones that comply with international guidelines."

The Health Protection Agency said the new study "may be indicative" of a risk but that "such analyses cannot be conclusive".

An £8.8million UK study whose findings were released last month found that, in the short term at least, mobile phone signals and base stations posed no risk.

The Swedish research is published in the latest issue of the journal Occupational Environmental Medicine.