A study by the Danish Cancer society has found no link between cell phone use and the incidence of brain tumors, contradicting recently reported studies that have linked cell phones and increased rates of brain cancer.
In a study of over 60,000 people in Denmark, Finland, Norway and Sweden diagnosed with brain tumors between 1974 and 2003, the researchers found that the rate of brain cancer remained stable, decreased or only increased gradually before the introduction of wireless devices.
Because rates of cancer remained stable after the dramatic rise in cell phone use in Scandinavia in the mid 1990s, the scientists were led to believe that there was no link to increased cell phone usage and brain tumors. But the findings are not definitively conclusive because widespread cell phone use hasn't been around long enough to see an increase in brain tumors, they say.
"Either it means that mobile phones don't cause brain tumors or it means that we don't see it yet or we don't see it because the increase is too small to be observed in this population, or it is a risk that is limited to a small subgroup of the population," said lead researcher Isabelle Deltour from the the Institute of Cancer Epidemiology at the Danish Cancer Society in Copenhagen, of the findings.
The researchers say they plan on continuing to monitor the study participants for the next several decades.
The report appeared in the Dec. 3 online edition of the Journal of the National Cancer Institute.