Cell phone radiation study finds more questions than answers

Cell phone radiation and a potential link to cancer risks have left consumers and scientists alike scratching their heads since mobile phones became widely used in the 1990s. Some studies have failed to show a link between radio frequency from cell phones and certain health problems, such as increased risks of tumours, while others suggest the opposite.

Now, two much-anticipated reports released Friday by the US Department of Health and Human Services' National Toxicology Program add to the cell phone conundrum. The studies were a part of the National Toxicology Program's 10-year, $25 million assessment of radiation exposure and potential health effects.

The comprehensive research reports detail findings from two large animal studies -- one in rats and one in mice -- that link high levels of cell phone radiation to some evidence of carcinogenic activity in male rats, including a rare type of a tumour, called a schwannoma in their hearts. There were no such significant findings in the female rats. Similarly, no significant findings emerged in the mouse study, according to the reports.