Don’t hang up yet: the latest study linking mobile phones to cancer has big problems


This article is by Rodney Croft, Professor of Health Psychology, University of Wollongong. It originally appeared on The Conversation.

opinion/analysis You may have seen the headlines over the weekend, reporting on a new study that’s supposedly found a link between mobile phones and cancer. But all is not quite as it seems. And much of the alarm raised by the study is misplaced.

First, a bit of background. The study was set up by the US National Toxicology Program (NTP) in response to concerns about the potential health effects of radiofrequency (RF) emissions from mobile telecommunications devices. It was set to determine whether chronic RF exposure caused cancer in mice and rats.

This was a large, well-funded study, and as such has been eagerly awaited by RF health scientists and policy makers alike. The issue of whether RF emissions can cause cancer has been hotly debated, and the evidence to date has been unable to settle the matter conclusively.

The report concludes that: “[…] the observed hyperplastic legions and glial cell neoplasms [cancer] of the heart and brain [in rats] were likely caused by the RF.”

In short, it found radiation similar to that generated by mobile phones appeared to cause cancer in some rats.


But it’s difficult to interpret the report in the proper light because it was released without normal scientific evaluation. The authors argued that they did this because of both strong media interest and the importance of the results to human health.

This argument would suggest that they had shown something sufficiently unambiguous to clarify this important issue. The problem is, the results of this report are far from unambiguous.

Even given that science can never be 100% certain of its conclusions, there is still reason for me to believe that the report’s conclusions have overstepped the mark.

First, in terms of the generalisability to public health, it is important to note that the study did not use exposure levels relevant to mobile phones.

It used whole body average specific absorption rates (SARs) of 1.5 watts per kilogram of body mass, three watts per kilogram and six watts per kilogram. But the maximum allowable SAR for the general public is 0.08 W/kg.

This does not make the results of the report meaningless, as even at six watts per kilogram, this would be a novel finding. But science has already found that very high RF levels can cause tissue damage. Even if they’re true, the conclusions would not require an urgent public health communication.

Second – and perhaps more importantly – there are a number of counter-intuitive results and missing details that require clarification before the conclusions can be accepted. These oddities were highlighted by internal reviewers listed in the report, but their concerns have yet to be fully addressed.

For example, the control animals – those that weren’t exposed to high levels of RF emission – died earlier than the RF exposed animals. We also expect control rats to develop some tumours over their lifetime, and the control rats in this study had none.

This raises questions about the adequacy of the controls. The issue was raised by reviewers, with one noting that if the RF group was compared to a normal control group (by adding just one tumour to the control group) that the finding would no longer be statistically significant.

Further, information about how the statistics accounted for the early death rate is missing. If tumours in the RF groups developed after the controls had already died, then this would skew results and so needs to be carefully dealt with.

Also missing is crucial information about randomisation, which a reviewer noted can lead to differences in survival rates.

Similarly, other important information is not provided – such as results from the equivalent analyses in mice – making it very difficult to know if the findings merely represent chance.

Off the hook

Given these issues, it is clear that greater detail and scientific review is required to know whether the results are important to science and the public. This goes against the claim by the report’s authors that urgent publicity for the study is warranted.

The NTP study will need to be fully evaluated once further details requested by internal reviewers become available. And it will need to be considered within the context of the RF bioeffect literature more generally.

At present, though, and particularly given the uncertainties regarding its results, the NTP report does not provide reason to move from current scientific consensus that mobile phone-like exposure does not impact health.

I agree with two of the report’s reviewers, who state that “additional experiments are needed to assess if the incidence of brain gliomas in male rats exposed to GSM- or CDMA- modulated RFR is significantly higher than the control group or not”, and “I am unable to accept the authors’ conclusions”.

By Rodney Croft, Professor of Health Psychology, University of Wollongong This article was originally published on The Conversation. Read the original article.


  1. Mobile is totally insecure by design, unstable and a scam. About time it’s put out to pasture and replaced with something like Lifi and VOIP ? Insecure noisy wifi the same.

    They have SAR ratings for a reason. And 0.08 is not correct. The Iphone 1 was released with a SAR rating of 1.7 , the motorola and HTC were the same.

    I don’t need a study to tell me wifi has it’s problems. As soon as I turn AC on it produces serious headaches and my brain starts throbbing. It’s almost instant and you can blind test me all you like. Wifi AC is a marketing scam and falls over after a few meters and does bugger all to fix noise problems.

    Turn wifi off at night or you won’t sleep properly. I have a tower behind houses across the road that was put there without any opposition and I can’t sleep here properly. I notice this as when I go to my girlfriends house I sleep like a log.

    If they say it does cause problems then clearly it doesn’t have the backing with bribes from telcos to cook the books ? “Studies” are cooked up all the time depending who is backing it or to get funding for instance hence why so many get pulled all the time.

    • “Mobile is totally insecure by design”. GSM is for sure but it is being phased out. What about 4G/LTE though?

        • danielr obviously, he’s pretty much running the gamut of conspiracy theories in one post. Electrosensitivity and big-telecoms are out to get us.
          Also using personal anecdote as if it was real evidence. Add in some homeopathy and faked moon landings and I’d have a complete bingo card ;)
          I’d suspect trolling except there are plenty of people like danielr who still somehow manage to force themselves to use all the technology that these evil companie produce…

          Oblig xkcd reference:

    • Have you done a blind test ? It’s very easy to fool yourself about these kind of things (There is a billion dollar alternative medicine industry built around people kidding themselves).

      It’s not hard to do a test, although it requires some patience. Have a friend in a different room (i.e. somewhere you have no possible way of communicating with him/her) turn WiFi on or off on the basis of a coin flip at five minute intervals over the course of two hours, and record whether you think it is on or off at the same intervals. The odds of you getting it right by chance more than 20 out of 24 times is less than 1%.

      If you really can detect WiFi, it would be a novel result. You could get it published.

  2. At a rough estimate, to get to 1.5 W of power absorbed per Kg of body mass, you would have to cover your entire body with mobile phones 3 layers deep, and have them all transmitting continuously at maximum power. The heat output from the phones in this arrangement would result in death from heatstroke inside of 20 minutes.

    • … although admittedly it might be possible get to 1.5 W/Kg over a very small portion of your body with a single phone.
      If you use a phone all the time, getting a headset is a good idea. Not only will it reduce the very small (and probably non-existent) risk of cancer, it will reduce neck and shoulder pain, and reduce the risk of accidents because you have a extra hand free.

  3. For example, the control animals – those that weren’t exposed to high levels of RF emission – died earlier than the RF exposed animals.

    So if I apply the same logic as the tin-foil-hat brigade, this study proves that exposing myself to mobile phone radiation will help me live longer….. :-D

  4. I don’t always climb monopoles, but when I do I make sure it has active 80watt rru’s.

  5. Ignoring the tinfoil hat nutter, this article demonstrates that there is some very serious anti-science going on in the world of science. Seriously, publishing this tripe and saying it needs to be promoted heavily in the news? Who’s trying to advance their career here? Certainly they haven’t seen the inside of an ethics workshop to consider the mass panic caused by deliberately misleading the public with bad science an acceptable outcome – just look at the problems caused by that a$$hole behind the ‘vaccines cause autism’ idiocy.

    The author of this study should be hauled over the coals for this unethical, unprofessional and wholly unjustified scaremongering for personal gain.

  6. Considering the power levels used don’t equate to a phone, and the actual specifics seem to be missing (was there a lower incidence of cancer with lower levels), I wont be giving up my phone yet.

    Though I may not keep it in my shirt pocket in the future…

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