Electromagnetic hypersensitivity

Electrical sensitivity (ES), sometimes also called electrosensitivity or electromagnetic hypersensitivity (EHS), is a condition in which a person reports physical and / or psychological symptoms which appear to be aggravated by electric or magnetic fields or other electromagnetic waves at exposure levels tolerated by the general public. It is a matter of ongoing controversy as to whether there is a direct physical link between EMF exposure and the symptoms experienced by sufferers. Mainstream scientific opinion (as in Irvine 2005) suggests that so far no there is no robust evidence that such a direct connection actually exists. Sufferers and their support groups argue that the situation has become politicised to the extent that the outcomes of studies may have influenced by the widespread implications that acceptance of such a connection would have on future policy ( see the response of the support group Electrosensitivity UK to the Irvine 2005 report at http://www.electrosensitivity.org.uk/HPA-RPD%20Report.htm ).

Initial reports of ES in the medical literature focused on individuals who reported symptoms following work with visual display units. However, many other electrical devices have also been reported as causing symptoms and recent surveys of ES sufferers have found that mobile phone base stations, overhead power lines, electrical transformers and mobile phone handsets are now the most commonly cited sources of ill health (Röösli et al, 2004).

Symptoms and severity

The health effects reported by electrosensitivity sufferers tend to be subjective, non-specific symptoms. As yet, no consistent evidence has been found of any objective signs of disease in this group (Irvine, 2005). Initial Swedish and Nordic reports were mainly of facial skin effects attributed to extensive use of visual display units such as dry eyes and burning skin (Irvine 2005). However, recently in Europe as a whole and in the USA, more general symptoms have been reported. Surveys of ES sufferers have not been able to find any consistent pattern to these symptoms (Hillert et al, 2002; Röösli et al, 2004). Instead symptoms reflecting almost every part of the body have been attributed to EMF exposure.

A minority of people who experience ES are severely affected by it. For instance, one survey has estimated that approximately 10% of ES sufferers in Sweden are on sick leave or have taken early retirement or a disability pension, compared to 5% of the general population (Hillert et al, 2002), while a second survey has reported that of 3046 people who experienced 'annoyance' from electrical equipment, 340 (11%) reported 'much' annoyance (Carlsson et al, 2005). For those who are severely affected, ES can have a significant impact on their quality of life, causing physical, mental and social impairment and psychological distress (Röösli et al, 2004).

Prevalence

A questionnaire survey of 2,072 people in California found that the prevalence of ES within the sample group was 3.24% (95% CI 2.8–3.68%), with ES being defined as "Being allergic or very sensitive to getting near electrical appliances, computers, or power lines" (Levallois 2002, response rate 58.3%). A similar questionnaire survey from the same year in Stockholm County (Sweden), found a 1.5% prevalence of ES amongst the sample group, with ES being defined as "Hypersensitiviy or allergy to electric or magnetic fields" (Hillert 2002, response rate 73%). A more recent survey of prevalence of 'annoyance' relating to visual display units, fluorescent tube lighting and other electrical equipment among the general Swedish population reported the prevalence of 'much annoyance' relating to these devices to be 0.8%, 1.4% and 0.4% respectively (Carlsson et al, 2005).

An expert group from the European Commission also attempted to estimate the extent of ES within EU countries (Bergqvist et al, 1997). The group reported that estimates of the total number of cases differed substantially between countries as well as between the answering groups, with self aid group (SAG) estimates consistently around ten times higher than those of centres of occupational medicine (COM). Estimates ranged from less than a few cases per million of the population (COM estimates from UK, Italy and France) to a few tenths of a percent of the population (SAG estimates in Denmark, Ireland and Sweden). The group concluded that the differences in prevalence were at least partly due to the differences in available information and media attention around ES that exist in different countries. Similar views have been expressed by other commentators (Irvine 2005, section 4.6).

Role of electromagnetic fields in causing ES

By definition, individuals who report ES believe that EMF from common electrical devices can trigger or exacerbate their symptoms. However, as these fields tend to be much weaker than the exposure levels generally accepted to cause physiological effects, the role that EMF plays in the etiology of the condition has been the topic of much controversy: sufferers and their support groups are firmly convinced of a causal relationship with EMF's, whereas at present the majority of mainstream scientific opinion does not consider there to be robust evidence of such a link.

A systematic review was published in 2005 which looked at the results of 31 experiments testing the role of EMF in causing ES. Each of these experiments exposed people who reported ES to genuine and sham electromagnetic fields under single- or double-blind conditions (Rubin et al, 2005). The review concluded 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." Since then, at least three further double-blind experiments have been published (Regel et al., 2006; Rubin et al., 2006; Wilen et al., 2006), each of which has suggested that people who report electrosensitivity are unable detect the presence of EMFs and are as likely to report ill health following a fake or nocebo exposure as following exposure to genuine EMF.

Given this evidence, the World Health Organisation has concluded that "there is no scientific basis to link EHS symptoms to EMF exposure" (WHO fact sheet number 296). Disagreement over this continues, however, as exemplified by the Freiburger Appeal; a petition by medical doctors stating that "we can see a clear temporal and spatial exposure between the appearance of [certain] disease and exposure to pulsed high-frequency microwave radiation" (Freiburger Appeal, 2002). Over 2,000 doctors in the EU have now signed this appeal.

Treatment

No reliable treatment for ES is yet known, mainly because the causes of the condition remain unproven. Avoidance, as far as possible, is the main strategy practised by those who claim to suffer from severe ES; this presents major practical difficulties in modern society. Other methods often used by sufferers include screening/shielding (such as earthed/grounded metallic netting or paints), electrical filters and complementary and alternative therapy.

A 2006 systematic review identified nine clinical trials testing different treatments for ES (Rubin et al, 2006): four studies tested cognitive behavioural therapy, two tested visual display unit filters, one tested a device emitting 'shielding' EMF, one tested acupuncture and one tested daily intake of tablets containing vitamin C, vitamin E and selenium. The authors of the review concluded that "the evidence base concerning treatment options for ES is limited and more research is needed before any definitive clinical recommendations can be made. However, the best evidence currently available suggests that cognitive behavioural therapy is effective for patients who report being hypersensitive to weak EMFs."

See also

• Electromagnetic radiation hazard
• Mobile phone radiation and health
• Wireless electronic devices and health

References

1. Röösli M, Moser M, Baldinini Y, Meier M and Braun-Fahrländer C. Symptoms of ill health ascribed to electromagnetic field exposure - a questionnaire survey. International Journal of Hygiene and Environmental Health 2004;207:141-150.
2. Irvine, N (2005). "Definition, epidemiology and management of electrical sensitivity". Report for the Radiation Protection Division of the UK Health Protection Agency, HPA-RPD-010.
3. Hillert L, Berglind N, Arnetz BB and Bellander T. Prevalence of self-reported hypersensitivity to electric or magnetic fields in a population-based questionnaire survey, International Journal of Hygiene and Environmental Health 2002;205:353-60
4. Carlsson F, Karlson B, Ørbæk P, Österberg K and Östergren P-O. Prevalence of annoyance attributed to electrical equipment and smells in a Swedish population, and relationship with subjective health and daily functioning. Public Health 2005;119:568-577.
5. Levallois P, Neutra R, Lee G and Hristova L. Study of self-reported hypersensitivity to electromagnetic fields in California. Environmental Health Perspectives 2002;110(suppl 4):619-623
6. Bergqvist U, Vogel E, Aringer L, Cunningham J, Gobba F, Leitgeb N, Miro L, Neubauer G, Ruppe I, Vecchia P and Wadman C. "Possible health implications of subjective symptoms and electromagnetic fields. A report prepared by a European group of experts for the European Commission, DG V." Arbete och Halsa 1997:19.
7. Rubin GJ, Das Munshi J and Wessely S. Electromagnetic hypersensitivity: A systematic review of provocation studies. Psychosomatic Medicine;67:224-232.
8. Wilen J, Johansson A, Kalezic N, Lyskov E, Sandstrom M. Psychophysiological tests and provocation of subjects with mobile phone related symptoms. Bioelectromagnetics 2006;23:204-14.
9. Regel SJ, Negovetic S, Roosli M, Berdinas V, Schuderer J, Huss A et al. UMTS base station-like exposure, well being and cognitive performance. Environmental Health Perspectives 2006;114:1270-5.
10. Rubin GJ, Hahn G, Everitt BS, Cleare AJ & Wessely S. Are some people sensitive to mobile phone signals? Within-participants, double-blind, randomised provocation study. British Medical Journal 2006;332:886-889.
11. World Health Organisation (WHO) factsheet no. 296 on Electromagnetic Hypersensitivity (2005): see [1]
12. Freiburger Appeal (2002): see [2] (PDF)
13. Rubin GJ, Das Munshi J and Wessely S. A systematic review of treatments for electromagnetic hypersensitivity. Psychotherapy and Psychosomatics 2006:75;12-18.

External links

• ElectroSensitivity.Org – Information, Advice & Awareness of Electrical Sensitivity
• FEB – Swedish organisation for the electrically sensitive
• Electrosensitivity UK – British organisation for electrosensitive people