14 Jun 2007

Science, being Green, and the precautionary principle

I'm feeling the conflict between being involved in science and being in the Green Party. A lot of members of the Green Party are instinctively opposed to many modern technologies and scientific practices, such as animal research, GM and lately, mobile phone and WiFi radiation. This attitude often rests on the precautionary principle, the idea that if something might cause harm it is better to act as though it does cause harm rather than to hope that it won't. I'm not opposed to this principle, but I despair at the tendency of the green movement (and newspaper weekend supplements) to succumb to hype and scaremongering. A prime example is Julia Stephenson, who is the Kensington and Chelsea Green candidate, and is a columnist for the Independent. She wrote a column recently, titled "My war on electrosmog", describing her efforts to rid her life of electromagnetic radiation after having her feelings of fatigue 'diagnosed' by her naturopath (not her GP, mind) as due to 'electrosmog'. Sigh. Particularly infuriating is the advertisement at the end of the article of "Magnetic field protection boxes" (start at £235!), "Q-Link Pendants", "Anti-radiation mobile phone headsets" etc. at the bottom of the article. If anyone is interested, for a few pence I can fashion a tin-foil hat, which I can guarantee will be as effective. Luckily, Bad Science has come to the rescue, so I don't need to tackle this in exhaustive detail, but as I have responded to others in the Green Party on this issue before, I thought I might share my thoughts on the matter. Julia has responded to the outpouring of scorn from scientists, but her response that "Disconnecting my Wi-Fi made me feel better. End of. I don't need a degree in physics to work out if I feel well or ill" exactly highlights the problems with assessing public health issues or medical treatments on the basis of personal experience or anecdote.

One thing to highlight
(as Julia has correctly noted) is that with all the research in this area, skepticism is a virtue. Experience of the biases prevalent in the reporting of industry-sponsored pharmaceutical trials teaches us this, and the arena of electromagnetic radiation is no exception. A recent systematic review by Matthias Egger (who knows a thing or two about systematic reviews) found that studies sponsored by the telecomms industry are less likely to report significant effects of electromagnetic radiation. So don't take any of the conclusions of research in this area at face value!

My opinion is that some people might be sensitive to electromagnetic radiation from mobile phone masts or WiFi - but if it were a ubiquitous problem, then many more people would have reported problems. Anecdotally, I have Wireless broadband at home and I never get headaches or joint pain. I also regularly walk through WiFi hotspots with no noticeable symptoms. The problem with symptoms like headache, nausea etc. is that they are very non-specific, and can be psychological. An underlying condition may exist that causes migraine, but the symptoms may be misattributed to an external factor that happens to be present at the onset of the symptoms. I'd advise anyone experiencing a sudden onset of such symptoms to visit their GP (and not a naturopath).

There's a fair amount of evidence that strongly suggests that the symptoms experienced by those who believe that they are sensitive to electromagnetic radiation are not caused by that radiation. A systematic review by Simon Wessely (an editorial board member of BMC Psychiatry) found that "The symptoms described by "electromagnetic hypersensitivity" sufferers can be severe and are sometimes disabling. However, it has proved difficult to show under blind conditions that exposure to EMF can trigger these symptoms. This suggests that "electromagnetic hypersensitivity" is unrelated to the presence of EMF, although more research into this phenomenon is required".
A randomized provocation trial by the same authors (comparing those reporting EMR sensitivity to controls, and exposing some to mobile phone radiation, some to a carrier wave, and some to a sham exposure) found that "No evidence was found to indicate that people with self reported sensitivity to mobile phone signals are able to detect such signals or that they react to them with increased symptom severity. As sham exposure was sufficient to trigger severe symptoms in some participants, psychological factors may have an important role in causing this condition". Another systematic review by Prof Wessely and colleagues suggested that cognitive behaviour therapy may be useful for those reporting sensitivity to electromagnetic radiation.

As the experience of symptoms that patients associate with electromagnetic radiation exposure is likely to be psychological, this has possible implications for the precautionary principle. It has been argued that the precautionary principle, if coupled with overhyped warnings of risk, is potentially damaging: "Evidence is emerging that prior beliefs about the risks from modern technology are an important predictor of symptoms from perceived exposures. Thus, by distorting perceptions of risk, disproportionate precaution might paradoxically lead to illness that would not otherwise occur".

All this talk of electromagnetic radiation risks is very reminiscent of the fake documentary programme Brass Eye, and their take on 'Science'. This featured 'heavy electricity' caused by "particle accelerators sending huge jolts of power into domestic power lines... the devastating result is that huge masses of heavy electricity start randomly falling out of wires, and crashing on to anything below... Basically it is like getting hit by a ton of invisible lead soup". That pseudoscientific babble was read out (and believed) by the actor Richard Briers. If people will believe that, unfortunately they will believe anything.

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