A study across five northern European countries has concluded that there is no clear connection between using a mobile phone and developing brain tumours.

The study, published in the online version of the International Journal of Cancer earlier this month, looked at the link between mobile use and glioma (tumours) and is thought to be the biggest study of its kind.

Researchers interviewed 1,522 glioma sufferers and 3,301 cancer-free participants in Denmark, Finland, Norway, Sweden and the UK. They found that regular use of a mobile phone, duration of use, or the cumulative number of calls had no effect on the risk of developing glioma.

However, the international research team did show that those who have used a mobile for 10 years or more have a 39 per cent higher risk of developing glioma on the side of the head they typically hold their handset. It also showed that long-term users are 2 per cent less likely than average to develop a glioma on the side of the head where they do not hold their phone.

The study concedes that there could be a risk of error associated with recall, which could affect the reliability of the results.

Scientists have rounded on the research and warned that it should not put people off using their mobiles. The consensus appears to be that the results, analysed by the Radiation and Nuclear Safety Authority (STUK) in Finland, are of “borderline statistical significance”.

Professor Anssi Auvinen, Research Professor at the Radiation and Nuclear Safety Authority, told Telecoms.com on Friday that there “remains some uncertainty about the biases in the study”, particularly people’s recall of use over a ten year period. “We are estimating this”, Prof. Auvinen said.

Asked if people could rest assured that mobiles were, after several studies, now safe, Auvinen responded that while this study was by no means conclusive “more research is definitely needed. If you want a stronger understanding of how mobiles affect the brain there needs to be significantly more work done with more data and many more variations. It is important also that any new research should be done looking at current use, rather than historical use.”