Original articles
Hypersensitivity to electricity: Working definition and additional characterization of the syndrome

https://doi.org/10.1016/S0022-3999(99)00048-3Get rights and content

Abstract

Those who believe that electric appliances trigger adverse symptoms have coined the label hypersensitivity to electricity. Scientific research has not been able to identify a direct link between electromagnetic fields and symptoms, and no diagnostic criteria exist. Groups with reported hypersensitivity are very heterogeneous. A need exists for an operational working definition and improved characterization of groups. We report an investigation of symptoms and risk indicators associated with reported hypersensitivity to electricity—based on a survey at a high-technology, multinational telecommunications corporation. Comparisons are also made with patients referred to a university department of occupational and environmental health. No association was found between specific psychosocial work characteristics nor personal traits and hypersensitivity to electricity. We present skin and neurovegetative symptom indices. Results indicate that skin, and not neurovegetative symptoms, characterize the syndrome, at least during the first years of illness. For characterization, we propose a set of dimensions, including triggering factors, behavior, and duration of symptoms.

Introduction

For more than 10 years, there has been growing concern in Sweden about individuals who report nonspecific health symptoms that, according to their beliefs, are triggered by electric and/or magnetic fields from electric appliances or power lines [1]. A syndrome label (“hypersensitivity to electricity”) was coined in the late 1980s. The label is based on their interpretation of the cause of their ill health. Currently, the Swedish Association for the Electrosensitive (a self-help group in Sweden) has about 2000 members. In a population-based survey in the greater Stockholm area in 1997, 1.5% of the respondents reported hypersensitivity to electric or magnetic fields. But, so far, scientific research has failed to establish a direct link between low-frequency electric or magnetic fields and symptoms. Symptoms have occurred independently of whether or not the fields were present during double-blind provocation studies.

Situations and appliances reported to trigger symptoms are not typically characterized by high levels of electric or magnetic fields. The group, which reports hypersensitivity to electricity, is very heterogeneous in symptoms and in reported triggering situations. There are still no generally accepted diagnostic criteria; the use of the syndrome label is based solely on sufferers' conclusions that being in the vicinity of devices emitting electric or magnetic fields triggers symptoms. No pathophysiological markers have been identified. There are no symptoms (or combination of symptoms) that are pathognomonic for hypersensitivity to electricity. Furthermore, there is no objective test for possible hypersensitivity.

The initial focus in the middle of the 1980s was on skin symptoms reported to be triggered by work with video display units (VDUs) 2, 3. Epidemiological research confirmed an increase in skin symptoms among VDU workers, but no increases in clinically diagnosed skin diseases [4] or characteristic histological changes [5] have been proven. The prognosis for skin symptoms among VDU workers seems to be good in the majority of cases. Eriksson and coworkers reported a recovery rate of about 63% in a 5-year follow-up study [6].

In some cases, the illness progresses and new symptoms and additional triggering factors, such as electric appliances in general, are reported. The progress of ill health often leads to an inability to work and to social withdrawal due to an increase in avoidance behavior. In the vast majority of these cases, the initial symptoms were skin symptoms during VDU work. The question of whether hypersensitivity to electricity is merely the result of a progression of the same syndrome as skin symptoms, a secondarily triggered syndrome, or another entity altogether remains to be answered.

The reported symptoms might be either indications of new diseases, manifestations of previously subclinical diseases, or physiological reactions triggered or interpreted in a new way. To this date, hypersensitivity to electricity has not been shown to predispose, nor to be an indicator of, any known clinical disease 1, 7. But, there have been studies that indicate physiological differences in individuals with and without VDU-related skin symptoms [8]. An increase in amplitude of brain cortical responses to amplitude-modulated light (flickering light) have been shown for persons who report hypersensitivity to electricity as compared with controls [9].

Studies focused on causal factors and risk indicators have shown varying results. No causal factor that can account for hypersensitivity to electricity in general has been identified 1, 7. One possible reason for the lack of positive results is that study groups, usually based on only one criterion, such as “reporting hypersensitivity to electricity” or “reporting skin problems during VDU work,” have been too heterogeneous. In some cases, the distinction between these groups has also been unclear.

Heterogeneous groups might also be one explanation for the comparably poor results for treated groups, as a whole, in controlled trials and for reported effects of treatments. Taken together, these studies indicate that different approaches—ranging from cognitive therapy 10, 11 and acupuncture [12] to reduction of electromagnetic fields (case reports from the Swedish Association for the Electrosensitive, a self-help group in Sweden)—might be successful depending at whom they are directed. We still lack a method for identifying the action that will be the most efficacious for each individual; recommendations are given based on personal experience and taking into account each sufferer's situation.

The present controversy that has risen from the inconclusive results in scientific studies, as compared with the afflicted patients' convictions that electromagnetic fields are the cause of their ill health, clearly motivates further studies. Due to the lack of diagnostic criteria and any pathophysiological marker, studies on hypersensitivity to electricity are left with only the patients' self-reported interpretations of their ill health as the basis for the definition of cases. This situation presents obvious problems and difficulties—for example, in comparing the results of separate studies. In our opinion, there is a need, both in research and clinical handling, for an agreement on a distinct operational definition of hypersensitivity to electricity, or perhaps several definitions based on different subgroups. To form such an agreement, we must improve our knowledge of what distinguishes people with reported hypersensitivity to electricity from other groups. On the basis of this knowledge, future studies can focus on specific, relevant symptoms and define more homogeneous groups.

Here, we report an investigation focused on the differences in reported skin and neurovegetative symptoms as well as information on possible risk factors, such as personality traits and working conditions, between those reporting hypersensitivity to electricity and those who do not report this syndrome. The definition of a case is a person who has reported suffering from hypersensitivity to electricity in a self-administered questionnaire. The symptoms reported by persons experiencing this syndrome are nonspecific. The same symptoms are prevalent in many diseases and as physiological reactions in healthy populations. The aim of this study is to investigate which symptoms are more frequently experienced in the group of persons reporting hypersensitivity to electricity. Two indices are tested for possible use for estimating the severity of investigated cases—the hypothesis being that index scores increase with higher degree of suffering (having actively sought medical consultation) and/or longer duration of ill health. Results from both a health survey at a high-technology, multinational telecommunications corporation based in Sweden and from patients referred to the Occupational and Environmental Health Centre (OEHC) at Huddinge University Hospital are used. Based on the results, we propose five different dimensions for characterizing study groups.

Section snippets

Case–control study

The study group consisted of employees who participated in a health survey in 1990 at a Swedish high-technology, multinational telecommunications corporation (IT company). Information on individual and occupational factors was collected using a standardized questionnaire; 241 employees answered (response rate=71%). Age and gender distributions among respondents showed no statistical differences compared with results from other questionnaire assessments within this company.

Among the respondents,

Case–control study

We found no association in the health survey between purported hypersensitivity to electricity and mental well-being (GHQ) nor personal traits assessed as neuroticism and extraversion (EPI). The indices for mental demand at work, intellectual discretion, and control over the work process did not differ significantly between people reporting hypersensitivity to electricity and the control group. The same was the case for the anxiety index and the sleep quality index.

Table I shows the symptoms

Discussion

The present results indicate that the characteristic symptoms of hypersensitivity to electricity are skin symptoms and not neurovegetative symptoms, at least in the early years. Persons who report hypersensitivity to electricity complain of nonspecific vegetative symptoms, such as fatigue, headache, and difficulties concentrating, but not to a significantly higher degree than persons who do not report this hypersensitivity. This is somewhat contradictory to reports from the self-help group in

Conclusion

In this study, we have shown an aggregation of skin symptoms, but not neurovegetative symptoms, in people reporting hypersensitivity to electricity—but without extreme avoidance behavior. We presented an index for skin symptoms that may be used in future studies for comparisons of the degree of sensitivity between different groups. An index for neurovegetative symptoms was also suggested. But, with regard to this index, further investigations of groups with more pronounced hypersensitivity to

Acknowledgements

The authors express their gratitude to Clairy Wiholm for enabling us to survey the employees at Ellemtel Development Laboratory, and to the Swedish Council for Work Life Research for its support of the study on cognitive therapy for patients who reported hypersensitivity to electricity at the OEHC.

References (23)

  • M Sandström et al.

    Neurophysiological effects of flickering light in patients with perceived electrical hypersensitivity

    J Occup Environ Med

    (1997)
  • Cited by (44)

    • An idiographic approach to idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) part I. Environmental, psychosocial and clinical assessment of three individuals with severe IEI-EMF

      2022, Heliyon
      Citation Excerpt :

      Existing scientific models, most importantly those based on the predictive processing framework, attempt to include and integrate all known factors (Van den Bergh et al., 2017a,b). Despite the attempts made to establish a definition and measurement protocol (Belpomme et al., 2015; Bergqvist et al., 1997; Eltiti et al., 2007; Hillert et al., 1999, 2002), accepted diagnostic criteria for IEI-EMF, apart from the subjective reports of patients, are yet to be developed (Baliatsas et al., 2012a,b; Meg Tseng et al., 2011). Thus, the primary inclusion criterion of participants in IEI-EMF related research is self-reported sensitivity.

    • The effects of radiofrequency electromagnetic fields exposure on human self-reported symptoms: A protocol for a systematic review of human experimental studies

      2022, Environment International
      Citation Excerpt :

      The types of reported symptoms vary between individuals. The most commonly reported symptoms are headaches, sleep disturbances and tinnitus, among many others (Baliatsas et al., 2012a; Eltiti et al., 2007; Hillert et al., 1999; Oftedal et al., 2000; Röösli et al., 2004). To date, cluster analyses have not identified specific symptom clusters related to specific EMF exposure sources or to EMF exposure in general (Röösli et al., 2004) and the pattern of symptoms does not seem to be part of any recognized syndrome (ANSES, 2018).

    • The effects of radiofrequency electromagnetic fields exposure on tinnitus, migraine and non-specific symptoms in the general and working population: A protocol for a systematic review on human observational studies

      2021, Environment International
      Citation Excerpt :

      The types of reported symptoms vary between individuals. The most commonly reported symptoms are headaches, sleep disturbances and tinnitus, among many others (Baliatsas et al., 2012a; Eltiti et al., 2007; Hillert et al., 1999; Oftedal et al., 2000; Röösli et al., 2004). There is the possibility that different symptoms could result from different types of EMF exposure.

    • Electromagnetic hypersensitive Finns: Symptoms, perceived sources and treatments, a questionnaire study

      2013, Pathophysiology
      Citation Excerpt :

      The percentages of age-groups were (20–29) 1.1%, (30–39) 13.4%, (40–49) 19.9%, (50–59) 22.0%, (60–69) 29.0%, (70–79) 13.4% and 1.1% in age group (80–99) (Fig. 1). In previous studies EHS symptoms have been typically related to skin conditions of the face and chest and various neurovegetative symptoms [11,12]. In the present study a list of 68 varied health complaints were reported.

    View all citing articles on Scopus
    View full text