In the wake of “conflicting” findings regarding the potential link between the use of cell phones and the development of cancerous brain tumors, some experts have been hopeful that a long-term study might be able to calm fears and establish that mobile devices do not pose a risk.
While a new study published this week in the journal Cancer Epidemiology is unlikely to put an end to the debate, it does provide evidence from three decades of work finding cell phone use during that time did not result in an increase in brain cancer incidence across Australia.
The study found that there was no increase in brain cancer incidence rates among any age group except for those between the ages of 70 and 84 between 1982 and 2013, and that even in that age group, the increase dated back to 1982 – five years before mobile phones use even began.
This increased incident rate in older Australians was attributed to improved diagnostic detection, according to the authors of the new paper. They found no increase in brain cancer incidence that could be linked to the increased use of cell phone, which now tops 90 percent in Australia.
Cell phone use hasn’t changed cancer rates
Simon Chapman, emeritus professor in public health at the University of Sydney and the lead author of the study, explained in a recent article for The Conversation that he and his colleagues examined the link between age and gender-specific brain cancer incidence rate of nearly 20,000 men and 14,000 women, and national mobile phone usage data over a 29 year period.
They found that, despite the fact that a large percentage of the population had been using mobile phones for at least two decades, age-adjusted brain cancer incidence rates in those between 20 and 84 years old had increased only slightly in most males and were stable in women over the age of 30. The only significant increase was in those over the age of 70. However, data suggests that this predates cell phone use and is likely due to improved CT and MRI technology.
Chapman’s team also compared “the actual incidence of brain cancer over this time with the numbers of new cases of brain cancer that would be expected if the ‘mobile phones cause brain cancer’ hypothesis was true,” he added. “Here, our testing model assumed a ten-year lag period from mobile phone use commencement to evidence of a rise in brain cancer cases.”
Using a model that assumed that mobile devices would cause a 50 percent increase in incidence rates, they determined that had the phone hypothesis been true, a total of 1,866 cases would have been reported in 2012. Similarly, they used a second model that predicted a 150 percent increase among the heaviest phone users, or a total of 2,038 new cases. In both instances, however, the actual number was only 1,435.
“We have had mobiles in Australia since 1987. Some 90% of the population use them today and many of these have used them for a lot longer than 20 years,” Chapman said. “But we are seeing no rise in the incidence of brain cancer against the background rate.”
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