There is no link between the long-term use of a mobile phone and getting brain cancer, research suggests.
In what has been described as the largest study on the subject, researchers found that cancer rates in the central nervous system were almost the same in both long-term mobile phone users and people who do not use the handsets, the study published on bmj.com found.
There are more than five billion mobile phone subscribers worldwide and people have expressed fears that the electromagnetic fields emitted by holding a handset to the ear may cause adverse health affects.
But researchers, from the Institute of Cancer Epidemiology in Copenhagen, studied the whole Danish population aged over 30 and born in Denmark after 1925 by gathering information from the Danish phone network operators and from the Danish Cancer Register.
They analysed data of 10,729 central nervous system tumours between 1990 and 2007 and discovered that long-term mobile users - who had used the devices for 13 years or more - had similar cancer rates to non-subscribers.
The researchers said they observed no overall increased risk for tumours of the central nervous system or for all cancers combined in mobile phone users.
The authors said: "The extended follow-up allowed us to investigate effects in people who had used mobile phones for 10 years or more, and this long-term use was not associated with higher risks of cancer.
"However, as a small to moderate increase in risk for subgroups of heavy users or after even longer induction periods than 10-15 years cannot be ruled out, further studies with large study populations, where the potential for misclassification of exposure and selection bias is minimised, are warranted."