11 February 2011
Epidemiologists have renewed concerns over the safety of constant mobile phone use, warning that many previous studies were flawed.
Environmental health experts from Spain and Israel have questioned evidence suggesting mobile phone use does not increase brain tumour risk, saying participants in previous studies had low levels of phone use and only short follow-up.
Interphone, the largest study to date, followed up heavy users for a maximum of only 5 years, they wrote in the journal Occupational and Environmental Medicine (2011; 68: 169-71).
Risk is likely to be confined to a small proportion of the entire brain, so studies analysing all brain tumours together probably watered down the real risk, they added.
The evidence suggested long-term mobile phone users had an increased risk of solid brain tumours, and people in the highest bracket for call time - about 27 minutes daily - also had a 40% higher risk.
Heavy users had an increased risk of glioma in the temporal lobe.
"Even a small risk at the individual level could eventually result in a considerable number of tumours and become an important public health issue", the authors said, but added more research was needed.
They advised reducing mobile phone exposure, particularly for young people, through simple measures such as sending text messages and using hands-free kits.
Last Reviewed: 14 February 2011