WHO | Electromagnetic fields and public health

1/3 ページ

Fact sheet N°296
December 2005

Electromagnetic fields and public healthElectromagnetic Hypersensitivity
As societies industrialize and the technological revolution continues, there has been an unprecedented increase in the numberand diversity of electromagnetic field (EMF) sources. These sources include video display units (VDUs) associated withcomputers, mobile phones and their base stations. While these devices have made our life richer, safer and easier, they havebeen accompanied by concerns about possible health risks due to their EMF emissions.
For some time a number of individuals have reported a variety of health problems that they relate to exposure to EMF. Whilesome individuals report mild symptoms and react by avoiding the fields as best they can, others are so severely affected thatthey cease work and change their entire lifestyle. This reputed sensitivity to EMF has been generally termed “electromagnetichypersensitivity” or EHS.
This fact sheet describes what is known about the condition and provides information for helping people with suchsymptoms. Information provided is based on a WHO Workshop on Electrical Hypersensitivity (Prague, Czech Republic,2004), an international conference on EMF and non-specific health symptoms (COST244bis, 1998), a European Commission
report (Bergqvist and Vogel, 1997) and recent reviews of the literature.

What is EHS?
EHS is characterized by a variety of non-specific symptoms, which afflicted individuals attribute to exposure to EMF. The
symptoms most commonly experienced include dermatological symptoms (redness, tingling, and burning sensations) as well
as neurasthenic and vegetative symptoms (fatigue, tiredness, concentration difficulties, dizziness, nausea, heart palpitation,and digestive disturbances). The collection of symptoms is not part of any recognized syndrome.
EHS resembles multiple chemical sensitivities (MCS), another disorder associated with low-level environmental exposures tochemicals. Both EHS and MCS are characterized by a range of non-specific symptoms that lack apparent toxicological or
physiological basis or independent verification. A more general term for sensitivity to environmental factors is Idiopathic
Environmental Intolerance (IEI), which originated from a workshop convened by the International Program on Chemical
Safety (IPCS) of the WHO in 1996 in Berlin. IEI is a descriptor without any implication of chemical etiology, immunologicalsensitivity or EMF susceptibility. IEI incorporates a number of disorders sharing similar non-specific medically unexplained
symptoms that adversely affect people. However since the term EHS is in common usage it will continue to be used here.

Prevalence
There is a very wide range of estimates of the prevalence of EHS in the general population. A survey of occupational medical
centres estimated the prevalence of EHS to be a few individuals per million in the population. However, a survey of self-helpgroups yielded much higher estimates. Approximately 10% of reported cases of EHS were considered severe.
There is also considerable geographical variability in prevalence of EHS and in the reported symptoms. The reported
incidence of EHS has been higher in Sweden, Germany, and Denmark, than in the United Kingdom, Austria, and France.
VDU-related symptoms were more prevalent in Scandinavian countries, and they were more commonly related to skindisorders than elsewhere in Europe. Symptoms similar to those reported by EHS individuals are common in the general
population.

Studies on EHS individuals
A number of studies have been conducted where EHS individuals were exposed to EMF similar to those that they attributed
to the cause of their symptoms. The aim was to elicit symptoms under controlled laboratory conditions.

2010/01/29

WHO | Electromagnetic fields and public health

2/3 ページ

The majority of studies indicate that EHS individuals cannot detect EMF exposure any more accurately than non-EHS
individuals. Well controlled and conducted double-blind studies have shown that symptoms were not correlated with EMF
exposure.
It has been suggested that symptoms experienced by some EHS individuals might arise from environmental factors unrelated
to EMF. Examples may include “flicker” from fluorescent lights, glare and other visual problems with VDUs, and poor
ergonomic design of computer workstations. Other factors that may play a role include poor indoor air quality or stress in theworkplace or living environment.
There are also some indications that these symptoms may be due to pre-existing psychiatric conditions as well as stress
reactions as a result of worrying about EMF health effects, rather than the EMF exposure itself.

Conclusions
EHS is characterized by a variety of non-specific symptoms that differ from individual to individual. The symptoms arecertainly real and can vary widely in their severity. Whatever its cause, EHS can be a disabling problem for the affectedindividual. EHS has no clear diagnostic criteria and there is no scientific basis to link EHS symptoms to EMF exposure.
Further, EHS is not a medical diagnosis, nor is it clear that it represents a single medical problem.
Physicians: Treatment of affected individuals should focus on the health symptoms and the clinical picture, and not on theperson's perceived need for reducing or eliminating EMF in the workplace or home. This requires:a medical evaluation to identify and treat any specific conditions that may be responsible for the symptoms,a psychological evaluation to identify alternative psychiatric/psychological conditions that may be responsible for thesymptoms,
z an assessment of the workplace and home for factors that might contribute to the presented symptoms. These couldinclude indoor air pollution, excessive noise, poor lighting (flickering light) or ergonomic factors. A reduction ofstress and other improvements in the work situation might be appropriate.
zz

For EHS individuals with long lasting symptoms and severe handicaps, therapy should be directed principally at reducing
symptoms and functional handicaps. This should be done in close co-operation with a qualified medical specialist (to address
the medical and psychological aspects of the symptoms) and a hygienist (to identify and, if necessary, control factors in theenvironment that are known to have adverse health effects of relevance to the patient).
Treatment should aim to establish an effective physician-patient relationship, help develop strategies for coping with thesituation and encourage patients to return to work and lead a normal social life.
EHS individuals: Apart from treatment by professionals, self help groups can be a valuable resource for the EHS individual.
Governments: Governments should provide appropriately targeted and balanced information about potential health hazardsof EMF to EHS individuals, health-care professionals and employers. The information should include a clear statement thatno scientific basis currently exists for a connection between EHS and exposure to EMF.
Researchers: Some studies suggest that certain physiological responses of EHS individuals tend to be outside the normalrange. In particular, hyper reactivity in the central nervous system and imbalance in the autonomic nervous system need to befollowed up in clinical investigations and the results for the individuals taken as input for possible treatment.

What WHO is doing
WHO, through its International EMF Project, is identifying research needs and co-ordinating a world-wide program of EMF
studies to allow a better understanding of any health risk associated with EMF exposure. Particular emphasis is placed on
possible health consequences of low-level EMF. Information about the EMF Project and EMF effects is provided in a seriesof fact sheets in several languages www.who.int/emf/.

FURTHER READING
WHO workshop on electromagnetic hypersensitivity (2004), October 25 -27, Prague, Czech Republic, www.who.int/pehemf/meetings/hypersensitivity_prague2004/en/index.html

http://www.who.int/mediacentre/factsheets/fs296/en/print.html

WHO | Electromagnetic fields and public health

3/3 ページ

COST244bis (1998) Proceedings from Cost 244bis International Workshop on Electromagnetic Fields and Non-Specific
Health Symptoms. Sept 19-20, 1998, Graz, Austria
Bergqvist U and Vogel E (1997) Possible health implications of subjective symptoms and electromagnetic field. A report
prepared by a European group of experts for the European Commission, DGV. Arbete och Hälsa, 1997:19. Swedish National
Institute for Working Life, Stockholm, Sweden. ISBN 91-7045-438-8.
Rubin GJ, Das Munshi J, Wessely S. (2005) Electromagnetic hypersensitivity: a systematic review of provocation studies.
Psychosom Med. 2005 Mar-Apr;67(2):224-32
Seitz H, Stinner D, Eikmann Th, Herr C, Roosli M. (2005) Electromagnetic hypersensitivity (EHS) and subjective healthcomplaints associated with electromagnetic fields of mobile phone communication---a literature review published between
2000 and 2004. Science of the Total Environment, June 20 (Epub ahead of print).
Staudenmayer H. (1999) Environmental Illness, Lewis Publishers, Washington D.C. 1999, ISBN 1-56670-305-0.
For more information contact:
WHO Media centre
Telephone: +41 22 791 2222
Email: mediainquiries@who.int

Contacts | E-mail scams | Employment | FAQs | Feedback | Privacy | RSS feeds© WHO 20102010/01/29