07 June 2011

Unhealthful News 158 - Brief observations about mobile phones and brain cancer

A few days ago I wrote about how the flurry of news about mobile/cell phones causing cancer exemplified much of what is wrong with the IARC process.  I have decided to not delve deeply into the scientific evidence about this, but there were two observations I though I would make about the discourse.  For anyone who thinks that this is just not enough for the day (there must be one or two people out there who do not think that I "talk" too much :-), my more significant post of the day was at the tobacco harm reduction blog, in which I speculated as to whether the initiative to mandate plain packaging for cigarettes in Australia (which I have written about in this series) is actually a long con, where winning comes from losing.

At the height of the reporting about the mobiles and cancer scare, ABC News reporter Michael Murray floored me with the incredibly rare act of thinking like a health reporter should.  Perhaps someone else wrote something similar, but I did not find it.  Murray made that observation that if mobiles are bad for you, why have we not seen a spike in the brain cancers they supposedly cause, since heavy exposure to mobile phones has gone from about zero to over half of everyone in less than fifteen years?  Why have most of the studies that tried to find a link found nothing, even though a few, with most focus on a single one, suggested otherwise  (Aside: Yes, I am American, but I really think that "mobile phone" or "my mobile" are much better terms than "cellphone" or "my cell".)

Murray recognized the value of ecological data, which most health reporters and epidemiology researchers seem to not understand.  If there is much increase in risk due to an exposure and there is a huge increase in exposure, they we should be able to see the results at the population level.  But brain cancers are not increasing in incidence.

It is important to realize that it is not quite this simple.  If the exposure causes only a small risk then even with the huge increase in exposure it might be hidden by a downward trend due to other changes, with the net effect being no change or even a decrease.  As I pointed out in my previous post, the useless IARC process does not distinguish between important risks and trivial ones.  It is also possible, as Murray points out, that the lead time for the cancer or the length of exposure required is longer than we have had a chance to observe.  But he kind of muddles the point, because if this is true then there should be no evidence from the studies to date, and thus no IARC claim.

Of course, if one believes there is any genuine worry about the longer term, or that there is study evidence now, then it would not hurt to think about whether this calls for a change in behavior or technology.  The risk seems to be really small – anything big would have shown up unless it always took decades to manifest – so the benefits of mobiles presumably swamp the costs.  Indeed, this is clearly true despite the traffic fatalities they cause, a causal relationship which is very well established and that occurs at a greater rate than the speculated risks for cancer.  Still, why not be safe and use a hands-free earpiece and microphone.  It does not reduce the risks if you are driving (notwithstanding the completely clueless "drivers must use hands free only" laws) but at least it keeps your ear from heating up.

But the possible suggestion that this might be a cheap, easy, comfortable precaution to employ when it is convenient seemed to spark outrage among those that do not believe there is any risk (example).  It is not as if anyone was suggesting that people curtail mobile phone use or do anything else that threatened industry profits, the usual motivation for feigned outrage.  This must be real outrage.  But why? 

My only theory about this oddity:  Ever notice that offering a constructive suggestion about how someone uses a software tool or a hammer, or even sexual techniques, generally elicits a calm response, even if there is disagreement.  But suggest to someone they may be upshifting at too low RPMs, let alone that they should consider not feeding their baby that, and they go berserk.  Somehow using a mobile phone has become one of those things that is so much a part of someone's life, like driving or child rearing, that they think that there cannot be anything they do not know about it, and that trying to provide new information is treated like a personal insult.  That may be every bit as strange as the possibility that low-level microwaves can cause cancer.

1 comment:

  1. Thank you for this observation. As far as I can tell, there is indeed good ecological data to support the claim that whatever else may be going on with trends in brain cancers, mobile phones are an an unlikely culprit. At least I was willing to put my name behind such reports (doi: 10.1002/bem.20678, 10.1002/bem.20648).

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