After more than 10 years of research, the US government's National Toxicology Program (NTP) has released its final report into the effects of radio frequency radiation (RFR), like that emitted by cell phones, on rats and mice. The results suggest that high levels of RFR exposure can cause some cancers in the animals, however the conclusions have been labeled as "weak" and impossible to equate to humans.

The study, commissioned well over a decade ago and costing $US30 million, concluded that exposure to high levels of RFR could be associated with "clear evidence" of heart tumors in male rats. The report also concluded there was "some evidence" of RFR causing tumors in the brains and adrenal glands of male rats. This incredibly narrow conclusion also notes that the evidence is unclear as to whether there is an association between these cancers and RFR in female rats, or mice in general.

So what does all this mean to the average person walking down the street with an iPhone to their ear? Virtually nothing.

The study concentrated on RFR frequencies used by 2G and 3G mobile phones. While 2G networks are still prevalent in Africa and South America, most phones in the US, Asia and Europe utilize 3G and 4G technology. Newer technologies often employ higher frequencies than the primary 900 megahertz frequency used by 2G technology. The upcoming 5G generation in particular focuses on a higher frequency band than any previous iteration, and there is a suggestion that higher frequency bands are less successful at penetrating the bodies of animals.

Michael Wyde, lead toxicologist on the NTP studies, cannot say whether 5G technologies would be more or less safe than the RFR frequencies examined in this study, but he does clearly note that its effects may be significantly different from what this research investigated.

"5G is an emerging technology that hasn't really been defined yet," says Wyde. "From what we currently understand, it likely differs dramatically from what we studied."

Other than the fact that the technology the study focused on has already become outdated, the exposure levels the animals were subjected to could not at all be compared to what a human is normally subjected to. The highest exposure level in the research was around four times higher than the maximum legal limit, and the animals received radiation across their entire body. John Bucher, a senior scientist working on the NTP project, openly admits that this kind of RFR exposure is not at all comparable to human cell phone use.

"The exposures used in the studies cannot be compared directly to the exposure that humans experience when using a cell phone," says Bucher.

Kevin McConway, from Open University, says the research tells us nothing about the risk of phone use in humans, and even the evidence that RFR causes tumors in rats is "pretty weak." So what does this study tell us then?

"Well, it establishes that, under certain conditions radiation of the same kind as produced by some mobile phones, but generally much stronger and much longer lasting, can lead to an increase in a certain type of tumor in certain rats," says McConway. "That's worth knowing, but it's a bit like a hypothetical experiment where rats are run over by heavy boulders. That would doubtless establish that heavy boulders have the potential to harm rats, but it doesn't tell us anything at all about the risk to humans arising from the existence of heavy boulders in the world. To investigate that risk requires a completely different type of research."

The big line coming out of this research is that RFR is associated with "clear evidence of tumors in the hearts of male rats." While this statement is essentially an accurate conclusion from the expansive and rigorous study, it can easily be misinterpreted by more hyperbolic news outlets. In fact, a quick glance at some reporting of this news reveals incredibly disingenuous headlines, such as, "'Clear evidence' mobile phones ARE linked to cancer, landmark study finds" and "Landmark study finds cellphones are linked to cancer."

The truth is that cell phones are no more or less safe than they were yesterday, and over a decade of relatively inconclusive research has struggled to find a clear connection between their use and cancer. Even this new study presents some strikingly incongruous findings.

Alongside the cancer risk only being clearly identified in male rats, and not females, those male rats exposed to RFR strangely displayed, on average, longer lifespans. This was hypothesized to be explained by an associated decrease in chronic kidney problems observed in the exposed male rats. So high levels of RFR exposure can decrease the chances of chronic kidney problems? No one is seriously suggesting that, just like no one can confidently claim that cell phones cause cancer.