According to headlines trumpeted around the world, cell phones are safe. This “reassuring” conclusion rests on an analysis of trends in brain cancer in Scandinavian countries up to 2003, which did NOT tie these trends in any way to actual patterns of use of cell phones.
Researchers analyzed annual incidence rates of two types of brain tumors -- glioma and meningioma -- among adults aged 20 to 79 from Denmark, Finland, Norway, and Sweden from 1974 to 2003.
Over the 30 years, nearly 60,000 patients were diagnosed with brain tumors.
"In Denmark, Finland, Norway, and Sweden, the use of mobile phones increased sharply in the mid-1990s; thus, time trends in brain tumor incidence after 1998 may provide information about possible tumor risks associated with mobile phone use," the researchers wrote.
They did see a small, steady increase in brain tumors, but it started in 1974, long before mobile phones existed.
"No change in incidence trends were observed from 1998 to 2003," they added. That would have been when tumors would start showing up, assuming it took five to 10 years for one to develop, they said.
It is possible, Deltour's team wrote, that it takes longer than 10 years for tumors caused by mobile phones to turn up, that the tumors are too rare in this group to show a useful trend, or that there are trends but they are in subgroups too small to be measured in the study.
It's known that brain tumor latency can be at least 30 years, so some consider this absurd to try and draw conclusions from this short period of time. Also, the researchers did not mention age-specific incidence of brain tumors, even though you will see an increase in age-specific incidence of brain tumors before an increase in the general population.
Further, the data was actually collected and available through 2007, but the researchers cut the analysis off at 2003. This is currently being investigated to find out if the extra four years of data would change the study results.