Although concerns have been raised regarding the radiation from cellphones and its connection with brain cancer, data to support these worries has failed to provide a concrete link between cellphone use and cancer. Now, a new study reports that low levels of radiation from cellphones caused brain tumor growth in rats that were exposed to it for long periods of time.
The findings released by the National Toxicology Program have yet to be peer-reviewed, but the link discovered between cellphone radiation and cancer in mice could finally provide proof of cellphone radiation being carcinogenic.
Despite the "game changing" results, further research is necessary to determine the exact nature of the link. As of now, the data only found higher rates of cancer in male rates, and the amount of radiation exposure necessary to be carcinogenic could be much higher in humans. Nevertheless, the team believes that their findings are important.
"This is by far - far and away - the most carefully done cell phone bioassay, a biological assessment," said Christopher Portier, the retired head of the National Toxicology Program who launched the study. "This is a classic study that is done for trying to understand cancers in humans. There will have to be a lot of work after this to assess if it causes problems in humans, but the fact that you can do it in rats will be a big issue. It actually has me concerned, and I'm an expert."
The team exposed over 2,500 rats, both male and female, to cellphone radiation for nine hours each day for up to two years.
The results revealed that between two to three percent of the male rats exposed to the radiation developed glioma tumors in their brains, and between six to seven percent developed schwannoma tumors in their hearts. Female rats and those not exposed to radiation had normal levels of cancer.
Interestingly, the two types of tumors observed in the study have been linked to cellphone use in a previous study that examined humans.
Although the findings are promising, the National Institutes of Health is questioning how the study was conducted and comparing it to previous studies.
"This study in mice and rats is under review by additional experts," they said. "It is important to note that previous human, observational data collected in earlier, large-scale population-based studies have found limited evidence of an increased risk for developing cancer from cell phone use."
The findings were published in the May 26 issue of the pre-print server bioRXiv.
