New study shows no link between mobile phone use and cancer

The biggest study on the subject to date has found no link between the long term use of mobile phones and tumours of the brain or central nervous system.

Danish researchers looked at 358,403 mobile phone subscribers over an 18-year period and found no evidence of raised brain tumour risk.

Previous studies on on the subject have been inconclusive, particularly about the effects of long-term use. Case control studies involving small numbers of long term users were shown to be prone to error and bias.

The International Agency for Research on Cancer (IARC) recently classified radio frequency electromagnetic fields, as emitted by mobile phones, as possibly carcinogenic to humans.

The latest study was an extension of a nationwide Danish study that looked at mobile phone subscribers from 1982 to 1995, later extended to 2002. These studies found no evidence of increased tumour risk.

The current study, led by the Institute of Cancer Epidemiology in Copenhagen, continued the study up to 2007.

It looked at data on the whole Danish population aged 30 and over and born in Denmark after 1925, split into mobile phone users and non users before 1995.

It found that 10,729 central nervous system tumours occurred in the period 1990-2007. However, when the figures were restricted to those who had used mobile phones for 13 years or more, cancer rates were similar for mobile phone subscribers and those who did not use a mobile phone.

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 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," the authors wrote.

“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.”

The study, which is published in the British Medical Journal, was accompanied by an editorial, in which Professors Anders Ahlbom and Maria Feychting at the Karolinska Institutet in Sweden said the new evidence is reassuring, but continued monitoring of health registers and prospective cohorts is warranted.

This article was published on Fri 21 October 2011