I Wasn’t Too Impressed By The BBC’s piece on ‘Wifi Refugees’ and EHS

13 Sep

Hey @bbchealth this article on EHS http://www.bbc.co.uk/news/world-us-canada-14887428 was under researched and failed to be at all informative.

WHO have already issued an official report on electromagnetic radiation. It’s very thorough. You’ll find their results on Electromagnetic Hyper-Sensitivity (EHS) on the second page http://www.who.int/peh-emf/about/WhatisEMF/en/index1.html. In the section on electromagnetic radiation’s effect on health in general they state

“In the area of biological effects and medical applications of non-ionizing radiation approximately 25,000 articles have been published over the past 30 years. Despite the feeling of some people that more research needs to be done, scientific knowledge in this area is now more extensive than for most chemicals. Based on a recent in-depth review of the scientific literature, the WHO report concluded that current evidence does not confirm the existence of any health consequences from exposure to low level electromagnetic fields.”

On EHS specifically the WHO report states

“There is little scientific evidence to support the idea of electromagnetic hypersensitivity. Recent Scandinavian studies found that individuals do not show consistent reactions under properly controlled conditions of electromagnetic field exposure. Nor is there any accepted biological mechanism to explain hypersensitivity. Research on this subject is difficult because many other subjective responses may be involved, apart from direct effects of fields themselves. More studies are continuing on the subject.”

If you need further understanding on why EHS may be due to nocebo effects (the evil twin of the placebo effect), incorrect attribution (there really is a problem but the wrong thing has been blamed as the cause) then there are some good articles around.

My problem with the BBC piece is that it seems to state “But EHS is not medically recognised in the US.” as if this is due to ignorant or dismissive scientists and health professionals that can’t be bothered to study the condition. Which has not been the case. It also claims that this is a ‘debated condition’ which gives the sense that their is controversy with the evidence, which seems to be false. It quotes a study by Dr. Marino claiming that “The study provides direct evidence that linking human symptoms with environmental factors, in this case EMF,”. Though to give it credit it does quote a skeptical physicist and the World Health Organization on the matter.

Interested, I continued reading the WHO report, which concludes

“To date, scientific evidence does not support a link between these symptoms and exposure to electromagnetic fields. At least some of these health problems may be caused by noise or other factors in the environment, or by anxiety related to the presence of new technologies.”

Then this is pretty good and short, not specifically on EHS but explains the science behind why it’s highly implausible. http://scienceblogs.com/builtonfacts/2009/09/wifi_and_radiation.php

This one is good too, talks about some other myths – wifi – cancer http://scienceblogs.com/insolence/2010/08/oh_no_school_wifi_is_making_our_kids_sic.php

This one makes a very important point, which is pretty funny

“In closing, I wanted to leave those who still fear cell phone and similar radiation with this thought: you are constantly bathed in electromagnetic radiation of higher frequency & energy every time you turn on a lightbulb or take a walk in the sunlight. It’s called visible light (wavelength 400-700nm), and if you are honest in your fear of EM-radiation, then you might want to be certain to live the rest of your life in the dark. You know, just to be safe in keeping with the Paralyzing Precautionary Principle.”

http://skepticalteacher.wordpress.com/2009/04/02/electromagnetic-fields-cancer-myths/

This piece has a lot of references for the more sciencey minded people. Again, the focus is on cancer but the mechanism for any plausible action is the same http://www.skepdic.com/emf.html and they do mention EHS

“At this time, it looks as if hypersensitivity to EMFs is a psychosomatic disorder.* (For example, a research team in Norway (2007) conducted tests using sixty-five pairs of sham and mobile phone radio frequency (RF) exposures. “The increase in pain or discomfort in RF sessions was 10.1 and in sham sessions 12.6 (P = 0.30). Changes in heart rate or blood pressure were not related to the type of exposure (P: 0.30–0.88). The study gave no evidence that RF fields from mobile phones may cause head pain or discomfort or influence physiological variables. The most likely reason for the symptoms is a nocebo effect.”)”

This blog covers a lot of different topics and can be pretty interesting. Has a couple of facts such as

“what is the exposure from Wi-Fi networks? Such exposures to EMF are typically thousands of times less than current safety limits. In fact, one review found:

In all cases, the measured Wi-Fi signal levels were very far below international exposure limits (IEEE C95.1-2005 and ICNIRP) and in nearly all cases far below other RF signals in the same environments.

So not only are exposures from Wi-Fi access points thousands of times less than safety limits, they are also less than the background radio frequency (RF) radiation.

Is there evidence for biological effects on cells? An extensive review of this research concluded:

Overall, there is little evidence of cellular effects of RF fields of health significance below current safety limits.

While they argue for further research in some areas, they were also including cell-phone level exposure, which remember is 100 times that of Wi-Fi, which in turn is no higher than background radiation.

What about electromagnetic hypersensitivity – the reporting of common non-specific symptoms, such as headache, fatigue, dizziness, and confusion, while being exposed to EMF? Well, the same review also summarizes this research, which finds that under blinded conditions there is no such hypersensitivity syndrome. Even with people who consistently report symptoms with exposure to EMF, in blinded conditions they cannot reliably tell if they are being exposed to EMF.”

http://www.skepticblog.org/2010/08/16/banning-wi-fi-from-schools/

Seems odd the ‘unbiased’ BBC would mention a very poorly conducted study with a positive result which supposedly supports EHS theory and forget to mention that the weight of evidence completely disagrees with this. With a number of studies, that were designed more appropriately to testing whether or not EMF relates to the symptoms experienced in self diagnosed ‘EHS’ demonstrating it’s a nocebo effect.

Is this one of those ‘false equivalence’ manufactured controversies again?

I thought the BBC recently promised to stop the misguided attempts to balance opinion as equal to evidenced based theories, and instead of ‘equal weight’ were going to give ‘due weight’?

Seems not so much, at least not in this instance.

After a quick and not at all extensive, google scholar search, that anyone – especially the journalist of the article could (or should) have performed I found some studies that were better conducted than the one mentioned. They concluded things like “Short-term exposure to a typical GSM base station-like signal did not affect well-being or physiological functions in sensitive or control individuals. Sensitive individuals reported elevated levels of arousal when exposed to a UMTS signal. Further analysis, however, indicated that this difference was likely to be due to the effect of order of exposure rather than the exposure itself” (Eltiti et al., 2007). Another states “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” (Rubin, Munshi, & Wessely, 2005) and a more recent update of that systematic review (Rubin, Nieto‐Hernandez, & Wessely, 2010) reports the results of 15 new experiments, bringing the total to 46 blind or double-blind provocation studies. Again the conclusion is that there is no robust evidence to supprt the EHS thoery. Rubin, Nieto-Hernandez & Wessel (2010) found that the results of studies included in their review did support the role of the nocebo effect in triggering the symptoms of EHS sufferers.

Finally I think it’s time to look at the Dr. Andrew Marino study – McCarty et al (2011) in the journal of neuroscience.

For a start the study itself states “direct evidence of nonpsychological EMF hypersensitivity is lacking.” in it’s introduction. The study also featured only one participant. Hardly a powerful study size. This isn’t exactly a generalizable or representative sample. This is a huge problem with the study.

It also wasn’t very realistic. People suffering claim their symptoms get worse when a TV is on, or when they use a mobile phone, or wifi. This study involved a metal plate above the subjects head. This may not be a large problem but it does seem strange, more realistic settings don’t seem unfeasible and have been used before.

McCarty et al (2011) found that an EEG while actively using a mobile phone produced no unusual readings. I’m not sure what the purpose of this was. It seems like an attempt to find a biological cause for EHS. It doesn’t work, so they bin the idea with little mention and move on. The authors also monitored the subjects sleeping EEG, it showed no unusual readings. However, the subject is suspected to possibly have a form of sleep epilepsy, and that this could have been the cause of many of her symptoms. However, the EEG set up was not set up in a way that could show this was or was not present. Whatever the point of this set up was, it did not support their ideas and gets quickly skimmed over.

MR showed cortical dysplasia in the right temporal lobe and right parietal polygyria (McCarty et al, 2011). This may seriously effect the validity of the study. Perhaps even some of the reported symptoms were due to this?

They measured a lot of different things. This increases the chances of finding a significance somewhere. It would be fine if these measures were used to explain possible confounding variables, however this doesn’t appear to have been the reason behind taking these measures. It seems more like they were looking for a biological mechanism but didn’t find it, so just state that they did it out of ‘thoroughness’ and dutifully report the unimpressive results. While they admit their study shows no plausible mechanism for EHS, I didn’t feel there was any rationale given for taking these measures or taking into account what relevance or implications they may have to the findings.

Whilst the results were significant the participant also did report symptoms in sham control and in actual continuous and actual pulsed exposure conditions. Whilst undergoing either sham or continuous exposure she reported similar severity and frequency of symptoms, these results were significantly different from pulsed exposure. It’s unclear why this should be the case, but this could be useful information. It seems important to note that the authors allowed the participant to report any symptom at any severity. This is interesting because they decided inconsistencies in symptom reporting were not important. So if the subject reports any mix of having a severe/moderate/some or no headache, feeling tired, feeling fine, feeling depressed, getting sore eyes, etc. or no symptoms at all in any mix of the sham or real conditions it doesn’t matter as long as the severity and frequency is statistically more often in the real condition. It’s unclear to me if this is an appropriate way of establishing a cause and effect relationship. It seems to me that it opens up the results more to chance. It would have been possible to look at the type and severity of symptoms which occurred in the sham condition and use this to rule out EMF as a cause. Excluding these when they occur in the real condition would make sense, since symptoms which occur regularly to the participant, even when not exposed to EMF, are very unlikely to be due to EMF exposure. Not exploring this problem actually places a barrier between both the patient and practitioners from understanding the true causes of such symptoms and the correct courses of action to fix or improve them. To me this seems an important thing to do, and I wonder would the result still have been significant if this had been taken into account in the analysis?

Though double blinded, it is reported that the participant was aware of a large amount of detail concerning the methodology of the study, this could possibly, though not necessarily, pose considerable problems (e.g. she may have decided to do anything at all possible to prove it’s not a nocebo effect and is really related to EMF so may have searched for clues or signs of how to do this that the researchers did not pick up on) but this drawback may have been difficult to avoid.

The authors also state that they found the subject reported feeling the presence of the electromagnetic field a statistically significant number of times. Contradictory to this, she also said she felt the presence of the field more times in the sham condition than actually whilst in the presence of the magnetic field. McCarty et all (2011) report that this rules out the psychological causes, they don’t explain why this contradiction would rule out psychological causes and why it doesn’t also rule out EMF causes. It would seem that one way the subject could have noticed the presence of EMF would be through the onset of her symptoms. As she couldn’t do this in this particular trial, to me this may support the nocebo effect theory of EHS.

In the introduction the authors cite a couple of studies which might show animals and humans can sometimes feel the presence of certain EMFs. They suggest this could be one way in which EHS manifests itself. It isn’t mentioned that this inability to distinguish the effects in this trial is contrary to that hypothesis. It’s also possible that the subject realised the authors thought that not being able to tell between sham and real exposure in this specific trial, would suggest to them that it isn’t caused by a psychological mechanism, and therefore she conflated the results.

I certainly didn’t feel the study had any clear, unequivocal findings.

There is very little special about this study. Perhaps it does suggest the possibility of someone suffering from EHS in some way, but even that is not entirely clear. Whilst Marino claims this study is direct evidence for EHS, it seems to me that it doesn’t answer any questions regarding EHS. At best it’s ‘direct evidence for EHS, in one person, but with a lot of questions left unanswered and some methodological limitations’.

It’s an unremarkable study and I’m not sure why it made the news. At any rate this study certainly doesn’t even come close to tipping the scales or providing any kind of equal scientific evidence for EMF causes of EHS when weighed up against the result of the systematic review of 46 previous studies (Rubin, Nieto‐Hernandez, & Wessely, 2010) and so the BBC article clearly places undue weight and focus on the McCarty et al (2011) study.

Eltiti, S., Wallace, D., Ridgewell, A., Zougkou, K., Russo, R., Sepulveda, F., Mirshekar-Syahkal, D., et al. (2007). Does Short-Term Exposure to Mobile Phone Base Station Signals Increase Symptoms in Individuals Who Report Sensitivity to Electromagnetic Fields? A Double-Blind Randomized Provocation Study.Environmental Health Perspectives115(11), 1603-1608. doi:10.1289/ehp.10286

McCarty, D. E., Carrubba, S., Chesson, A. L., Frilot, C., Gonzalez-Toledo, E., & Marino, A. A. (2011). Electromagnetic Hypersensitivity: Evidence for a Novel Neurological Syndrome. International Journal of Neuroscience, 110905022905006. doi:10.3109/00207454.2011.608139

Rubin, G. J., Munshi, J. D., & Wessely, S. (2005). Electromagnetic Hypersensitivity: A Systematic Review of Provocation Studies. Psychosomatic Medicine, 67(2), 224 -232. doi:10.1097/01.psy.0000155664.13300.64

Rubin, G. J., Nieto‐Hernandez, R., & Wessely, S. (2010). Idiopathic environmental intolerance attributed to electromagnetic fields (formerly “electromagnetic hypersensitivity”): An updated systematic review of provocation studies. Bioelectromagnetics, 31(1), 1-11. doi:10.1002/bem.20536

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