The concern that cellphones may lead to cancer has been bounced around for years—and partial results from a $25 million government study purport to have found such a link, though with major caveats, the Wall Street Journal reports. Per the so-far results of the multiyear National Toxicology Program study (which the Journal says has been peer reviewed, but the Washington Post says has not), "low incidences" of two types of tumors—brain "gliomas" and heart "schwannomas"—developed in rats exposed to high doses of radiofrequency radiation, or RFR, like that emitted from mobile phones. "Even a very small increase in the incidence of disease resulting from exposure to [RFR] could have broad implications for public health," the report released Thursday said. But, adds associate NTP chief John Bucher, “the results from our studies are far from definitive at this point,” per USA Today. For humans, “this may have relevance. This may have no relevance.”
To conduct the study, scientists directed RFR signals into the cages of pregnant rats, then into the cages of the babies for a total of nine hours every day for two years. In the end, 2% to 3% of dosed males contracted gliomas, and 6% to 7% contracted schwannomas. But "there was no significant cancer uptick in the female rats dosed with radiation," per the Post—and the radiation rodents actually lived longer than the control rats. That, in addition to other factors, has left some experts skeptical, noting that the study has only been partially completed and that rats are prone to what NBC News calls their "own unpredictable vulnerabilities to cancer," meaning humans may not face the same risks. All of this has led the Post to suggest a better headline for this report may be "Research That Hasn't Been Vetted Yet Shows Possible Link Between Cellphones and Cancer in Male Rats." Still, a former head of the NTP tells Scientific American, "It actually has me concerned, and I'm an expert." The full report is set to be released next year.