Mobiles 'don't raise cancer risk'

The research is the first to look at the effects of handset radiation levels on the brain.

Tokyo Women's Medical University compared 322 brain cancer patients and 683 healthy people.

It found no increased risk of the three main brain cancers among regular mobile users.

Professor Naohito Yamaguchi, whose findings were reported today in the British Journal of Cancer, said: "A central challenge with previous studies looking into the link between mobiles and cancer has been how to accurately estimate how much exposure different parts of the brain receive.

"We studied the radiation emitted from various types of mobile phones and placed them into one of four categories relating to radiation strength. We then analysed how they would affect different areas of the brain areas, taking into account the organ's complex structure.

"Using our newly developed and more accurate techniques, we found no association between mobile phone use and cancer, providing more evidence to suggest they don't cause brain cancer."

The patients involved all had one of three types of tumour - glioma, meningioma or pituitary adenoma - which together make up 85% of brain cancers.

The jury is still out on the question of whether or not mobile phones are safe.

Despite the rapid increase in mobile phone use since the 1980s, the number of people with brain tumours has hardly changed over that time.

Most studies have shown no association with cancer, although a few have pointed to a link.

The largest study to date, involving 420,000 people, failed to find any evidence of a cancer trend even after 10 years of use.