“hypersensitivity to electricity” in the office; symptoms ...r1997-v3-… · project, and...

INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 1997, VOL. 3, NO. 3-4, 129-140

“ Hypersensitivity to Electricity” in the Office; Symptoms and Improvement

Anna-Christina Blomkvist

Lulea University of Technology, Sweden

Nineteen persons "hypersensitive" to electricity and 20 nonafflicted persons were studied for1 Vi years. The most discernible hypersensitivity symptoms were pricking sensations and redness in the face, but these symptoms were present in only half of the afflicted. Other symptoms were similar to symptoms experienced during office work and this study does not support the idea that electrosensitivity is one single syndrome. The "hypersensitive" persons improved significantly, mainly on neuropsychiatric symptoms, but the skin problems sustained— as did the belief about their cause. The afflicted persons used less conventional medication than the group of the nonafflicted, which suggests a general tendency for attribution to environmental factors.

hypersensitive to electricity electrosensitivity office work skin problems

1. INTRODUCTION

In spring 1992, a project on “hypersensitivity to electricity” and the anxiety about such sensitivity was initiated by representatives from six Swedish governmental agencies. The m ain aim was to establish practices of remedy to be used at the initiators’ offices. An expert group was selected to provide support to the local occupational health services. M y role was to take part in the expert work, lead the project, and evaluate the employees’ subjective judgments of effects of our work on their well-being. The project was brought to a conclusion in early 1996. This report discusses symptoms and their changes, and attempts to relate these changes to external factors. The project was preceded by three exploratory interview studies, one of which was summarized in Blomkvist and Almgren (1995). An introduction to the problem was published earlier (Blomkvist et al., 1993), management’s (lack of) insight into the work of their staff has been commented in Blomkvist and Ostberg (1994), and a detailed Swedish report is available (Blomkvist, Hamnerius, & Klittervall 1996).

1.1. Symptoms and Causes

“Hypersensitivity to electricity,” hereafter referred to as electrosensitivity, covers various somatic and psychosomatic reactions attributed to the presence of electric

Correspondence and requests for reprints should be sent to Anna-Christina Blomkvist, Turbingrand 12, S-176 75 Jarfalla, Sweden. E-mail: < [email protected]> .

mailto:[email protected]

130 A.-CH. BLOMKVIST

equipment. The concept has been known in Sweden, the USA, and several other countries since the 1980s (see Grant, 1995). The same type of phenomenon may be present in other countries but under other names. Electrosensitivity openly manifests itself as a problem when afflicted persons wish to avoid electromagnetic fields, and consequently, Video Display Units (VDUs), telephones, copying machines, and so on. Sixty percent of all the middle-aged work force in Sweden use computers (Statistiska centralbyran, 1995), and office jobs generally require such a tool.

The electrosensitivity syndrome was described as skin symptoms and symptoms from the nervous system by Knave, Bergqvist, and Wibom (1989). Frequent self- reported symptoms from a sample of afflicted persons having received remedial measures' (Blomkvist & Almgren, 1995) were skin symptoms such as “pricking sensations in face,” “burning sensations,” “facial skin rashes,” and nervous system symptoms such as “extreme tiredness,” “headaches, and palpitation. Symptoms were generally associated with VDUs, but also with fluorescent light, transformers, and other electric equipment. Descriptions vary between reports, probably because there is no discernible diagnosis by which electrosensitive persons can be selected for study. Skin symptoms were emphasized by Oftedal, Vistnes, and Rygge (1995), and overlap with oral problems by Bergendahl, Anneroth, and Stenman (1994). W adman, Linder, Medhage, Knave, and Bergqvist (1994) attempted to form subgroups of those afflicted. They divided syndromes into skin problems only, skin problems with nervous system symptoms successively added, and nervous system symptoms already present at the debut of electrosensitivity.

Skin problems and tiredness are frequent complaints in offices. An unpublished study2 on about 300 office workers at the Swedish Vehicle Register and the Driving License Registries was carried out in the same time interval (1992-1994) as the present project, and showed that about 30% complained of dry skin, and at least the same percentage of tiredness. Bachmann and Meyers (1995) published results where 166 South African office workers were interviewed in accordance with Swedish studies on office work, and 35% of the employees complained of dry skm and 30% of tiredness. Skin problems are persistent (Eriksson, Hoog, Stenberg, & Sandstrom, 1995; W adman et al., 1994). It is known that women report more such symptoms than men (see, e.g., Nelson, Kaufman, Bucht, & Karr, 1995; Stenberg & Wall, 1995). Ideally, symptoms for pinpointing electrosensitivity would be distinguishable fromdry skin and tiredness.

In a round table discussion summary (Bergqvist, 1995) some thoughts on causes were mentioned. Debates on electrosensitivity and possible causes bring up conflicts between different views. Provocation studies with electromagnetic fields have not offered any explanations (Sjoberg & Hamnerius, 1995; Wennberg, Franzen, & Paulsson, 1995). The Swedish National Board of Health and Welfare (1995) published its view in early 1995, where psychological models were upgraded and medical models downgraded; the latter with the argument that there were no explanatory biological mechanisms and no successful provocation study. This did not settle the debate and

1 Via the former Working Life Fund.2 A study by Previa Rikshalsan. Data supplied by Christian Castwall, Previa Konsult, Stockholm,

Sweden.

“ HYPERSENSITIVITY TO ELECTRICITY” ; SYMPTOMS AND IMPROVEMENT 131

there are ongoing studies exploring plausible causes such as interference with signal substances3, activation of free radicals4, and flickering fluorescent light (Wibom, 1995).

1.2. Remedial Measures

According to Blomkvist and Almgren (1995), the most common counteracting steps taken by afflicted persons were to use filters for the VDUs, turn off fluorescent lights, stop working at VDUs, connect shields, tables, and fluorescent lights to earth, and minimize exposure from alternating electric fields in various ways such as choosing a battery calculator and moving electric equipment. These measures are examples of electric and magnetic sanitation (Blomkvist et al., 1993), and are generally requested by the afflicted persons. Other treatments suggested in Swedish studies are medical therapy, psychotherapy, acupuncture and changes in work organization (see, e.g., Arnetz, Berg, Anderzen, Lundeberg, & Haker, 1995; Berg, Arnetz, Liden, Eneroth, & Kallner, 1992), and shorter work spells (Gustavsson & Ekenvall,1992). Lower room temperature has been suggested by companies. Spontaneous recovery has also been observed (Liden, Reizenstein, Sedvall, & Ehn, 1996).

2. METHOD

Six offices, in which there were afflicted persons—or where management feared that electrosensitivity symptoms would arise after an upgrading of the computer equip- m ent were involved in the project. The expert group began by surveying each agency. Interviews and measurements of electromagnetic fields were carried out, and results were reported back to the local groups responsible for adjustments or changes in the work environment. Measurements were done according to what is now a Swedish standard SS436 1490 (Standardisation in Sweden, 1995), and an extended m ethod for the environment (Statliga sektorns arbetsmiljonamnd, 1995). After 1 '/2 years, the expert group returned and evaluated the effects of the changes. During the intervening period, the expert group had been available for discussion and further advice. Remedial measures taken by the local health services within the 1 '/2 years varied with circumstances and organizations. A t some agencies changes were minor. Interviews were carried out individually and following a questionnaire. D ata from the first and second visits are referred to as Interview I and Interview II.

2.1. Participants

The afflicted persons participating in the this study had labeled and reported their diagnoses themselves. The nonafflicted persons are regarded as a risk group. In Interviews I and II there were 19 afflicted persons; 11 women and 8 men, and 20

L. Ronnbock, Department of Clinical Neuroscience, Gothenburg University, sponsored by the Swedish Council for Work Life Research.

P.A. Ockerman, Department of Clinical Chemistry, Lund University, Sweden, sponsored by the (Swedish) Cancer and Allergy Foundation.


nonafflicted persons; 19 women and 1 man. Another 5 afflicted women were interviewed only once, after they felt satisfied with the remedial measures taken; 4 of them answered questions on medication, and their answers have been included in this paragraph.

2.2. Questionnaire and Computations

The questionnaire covered symptoms chosen from Knave et al. (1989) and a study parallel to the present project (see footnote 2). Further questions were added after advice from five “veterans”—members of an association of afflicted persons, FEB. The questionnaire contained about 50 questions on organization and physical environment and 80 on symptoms. The items were grouped under 11 headings: Organization, Physical Environment, Concern/Worries About the Job, No Fun/Dislike, Attitudes to Computer, Viewing Discomfort, Face/Skin, Body/Skin, Allergy, N europsychiatric Bodily Problems, and Neuropsychiatric Mind-Oriented Problems. There were also separate questions on sleep problems, medication, and avoidance of electric equipment. For Interview II three holistic judgments of well-being were added.

The answers to the questionnaire were dichotomized into 0 and 1. Complaints and symptoms scored 1. This means, in short, that a high sum of scores is bad. Fisher exact probability and x 2 was uscd for comparisons on single variables. An analysis of variance with repeated measures was carried out in accordance with suggestions by Winer (1970); Winer also defended analyses of variance of dichotomized data. Regression coefficients and /-tests were calculated on scores summed over persons.

2.3. Improvement Measurements

There is, as seen already, no clear definition of electrosensitivity and no characterizing symptom, neither does any general definition of “healthy” exist, and there are no readily applicable measurements of health improvement. Improvement was quantified here as the difference of the total numbers of symptoms of each individual between Interview I and Interview II. Other measurements used were a retrospective subjective judgment of well-being, and a holistic question on actual improvement. A local debate5 on improvement took place in 1993, when two companies tried to determine which of them was best at rehabilitating their afflicted employees. The companies focused on hours at work, whereas the present study evaluates subjective experiences.

3. RESULTS

First, a short summary of responses to items concerning the organization and environment is given. Then follows a description of the answers to questions on the symptoms. Last, data from remarks made by the interviewees in connection with the questionnaire as well as improvement measurements are shown.

5 Wiholm, C. & Johansson K.I. (1993). Missvisande siffror [Misleading numbers], Televarlden, 14, 17.


3.1. Organization and Physical Environment

The average age of the afflicted persons was 43, and of the risk group 45.5 years. The afflicted persons had been working with computers for about 16 and the nonafflicted for about 20 years. N ot all persons were full-time employees. On average, the afflicted persons worked 85% of full time at Interview I, and the nonafflicted 95%. At the time of Interview II the corresponding percentages were 78.5 and 95.5, respectively. Neither difference in time at work was significant. Nine afflicted persons worked more than 4 hrs a day in front of VDUs, as compared to 18 nonafflicted persons (p < .05). The reason for this difference was that the afflicted persons had already taken protective measures and lowered their exposure significantly at the start of the project, and this difference remained.

The m ost frequent complaints from afflicted persons were viewing discomfort (11 of 19), and worries about getting worse (10 of 18). The nonafflicted persons, often using computers all day, complained about noise (11 of 20), low salaries (10 of 20), unpleasant indoor climate (9 of 20), and high room temperature (9 of 20). The groups did not differ significantly on these variables, however.

Fisher exact probability test and x 2 on afflicted versus nonafflicted persons’ answers showed few differences with probabilities lower than 5% on the organization and physical environment items. In all, there were 7 differences at the 5% level or less within 49 paired comparisons of Interview I and 5 in Interview II. G roup differences were found under Concern/Worries About the Job, No Fun/Dislike, and Attitudes to Computer. The afflicted persons were skeptical about computers and about additional computer use. The afflicted persons also indicated “low identity at work,” that is, uncertainty about what would become of them, and what tasks they would manage in the future. The nonafflicted persons worried about changes in the organization and risk of losing their jobs. M ost of the group differences were easily understood; the afflicted persons had already, as said earlier, modified their environments according to their assumed needs. There were no differences indicating that electrosensitivity was caused by conditions at the different work stations.

W orries about symptoms lessened (from 10 to 4 of 19), and worries about losing job opportunities and related matters rose somewhat (from 2 to 4) by Interview II among the afflicted persons, so that the interval between the afflicted and nonafflicted decreased. However, afflicted persons more often felt that their jobs were known by their management, and at Interview II this group difference was significant (p < .02), when only 1 nonafflicted person claimed (1 of 20) that the management had insight into her job.

3.2. Most Frequent Symptoms and Typical Symptoms of ElectrosensitivityM ost frequent symptoms, reported by at least half of the afflicted persons in Interview I, were dry skin, poor physical condition, sensitivity to exposure to sunlight, problems while viewing, pricking sensations, redness, and upset stomach. They significantly (p < .05) exceeded the nonafflicted on four of the skin symptoms and five of the neuropsychiatric symptoms. W ithin the group of nonafflicted persons more than half complained of a dry complexion and psychic tiredness, and significantly more than the afflicted (p < .05).


At the time of Interview II more than half of the afflicted persons agreed to dry skin, redness, and pricking sensations. The nonafflicted persons mentioned problems with dry complexion, snoring, and fatigue. Further, the nonafflicted persons blamed their fatigue on “spring fatigue.” The first interview was undertaken in autum n 1992, but as the second interview took place IV i years later, it was then early spring. Afflicted persons made no references to the time of year, but there were positive comments about the cloudy weather of the previous summer.

The variable “afflicted” correlated significantly with the following symptoms: pricking sensation, redness, asthma, heavy limbs-feeling, and disturbed by light in both interviews. It should be noted that redness and pricking sensations in the face were the only symptoms in which the afflicted persons were over-represented at both Interview I and II. W ithin the group of the afflicted, redness correlated significantly with the opinion that the indoor air was dry and with dry skin, whereas pricking sensations correlated with eczema. Thus, they should not be regarded as two facets of the same symptom. Neither in Interview I nor II did pricking sensations and redness correlate with each other within afflicted persons.

3.3. Symptoms and ChangesTable 1 shows average number of symptoms reported by all persons. The afflicted persons reported significantly more symptoms than the risk group. As further seen in Table 1, there was a significant reduction in the number of symptoms within the group of afflicted persons from Interview I to Interview II 1 Vi years later (also reflected in a somewhat smaller constant a in Table 2). There was an insignificant increase in the number of symptoms within the nonafflicted group. This increase seemed to be explained by the spring fatigue already mentioned.

TABLE 1. Group Means and ANOVA Results. The Means Give the Average Number of Symptoms per Person in Each Group at Each Interview

Time Afflicted Nonafflicted Marginal Means

Interview I 20.26 13.35 16.72

Interview II 18.26 13.80 j 15.97

Marginal means 19.26 13.58

Note. Main group difference: F1.37 = 5.36, p < .05; Group difference at Interview I: U31 — 3.23, p < .01; Group difference at Interview II: t,37 = 1.57, p < .10; Difference among the afflicted from Interview I to II: t,37 = 2.13, p < .05.

Afflicted persons showed the largest decrease in symptoms in variables covering neuropsychiatric problems; mind oriented as well as bodily oriented. Also, face and skin problems diminished, but not mucous problems or allergies. A regression analysis of the afflicted persons’ responses against the nonafflicted persons’ shows that when nonafflicted persons have symptoms, these symptoms are even more


common among afflicted persons. This is seen in Table 2. Plotting showed that responses to two items formed an exception: H alf of the afflicted persons had redness and pricking sensations in the face, whereas there was only one such response in the nonafflicted group.

TABLE 2. Regression of the Number of Reported Symptoms in the Afflicted Group on the Nonafflicted Group; y = bx + a

Time rho b5% Confidence

Interval of b a5% Confidence

Interval of aInterview 1 .444 .535 + .253 3.789 + .926Interview II .598 .422 ±.248 3.289 ±1.031

Note, x = nonafflicted; y = afflicted.

Rank order of symptoms based on frequency of occurrence was compared to rank order of symptoms in Blomkvist and Almgren (1995) and in Bergendahl et al (1994). All rank orders in all these data, from the afflicted and nonafflicted correlated positively. The observation reinforces the statement that afflicted persons have a configuration of symptoms similar to other persons’ in office environments, but have the symptoms to a greater extent. Dry skin strengthens this pattern as does tiredness or fatigue, because they are common.

3.4. Gender Differences

In Interview I, the afflicted women claimed 27 symptoms each on an average, and the men 10 (p « .001). A t the time of Interview II, afflicted women made an average of 21 complaints, and the men still about 10. This latter gender difference was insignificant. Afflicted men did not haye more complaints than the nonafflicted persons (of which 95% were women) averaging 13 complaints during Interview 1 and 14 during Interview II. Women indicated several nervous system symptoms such as headache, feeling feeble, forgetfulness, and dizziness. M en m ore often chose

disturbed sleep.” The differences in number of symptoms between men and women confirms the expectations mentioned in the introduction.

3.5. Thoughts on Causes and Improvement

Findings about causes of electrosensitivity were not included in the scope of this project. However, some comments made by afflicted persons concerning causes, and some additional answers with relevance to improvement and medication are present in the data.

Amalgam sanitation and debut at the VDU are seen in Table 3. Afflicted persons attributing the cause to the VDU (p < .01) at an early stage of their illness, had not often undergone amalgam sanitation, and only one of them claimed sensitivity to other electric equipment. Among the five afflicted persons interviewed only once one was unclear about the attribution, and four reported no problems apart from those


recognized at (dual-page) VDUs. None of those five had undergone amalgam sanitation. It seems as if immediate attribution to VDUs restricts further thoughts on causes as well as needs for further remedial measures.

Afflicted and nonafflicted persons were asked about general well-being (on a scale from 0 to 10), and whether well-being was “getting better” (improving) or “getting worse.” The median well-being estimate was 7, and there was no difference between the afflicted and nonafflicted or men and women in this respect. A look at which single items could influence the well-being judgment showed that heartburn and pain from muscle tensions were the only items to correlate significantly negatively with well-being (t-test on well-being between persons with and without the symptoms gives p < .05 and p < .01, respectively), and these two items did not correlate withthe variable “afflicted.”

As if persons were confusing hope with prediction, they avoided the well-being “ getting worse” alternative. Only two (afflicted) persons said they were getting worse. One of these two claimed to be too old to ever get better (“It can only get worse at my age, can’t it?”). The other nonoptimist blamed flaws in the electric sanitation. Eighteen persons claimed to be stable—“always at same vigor” and 19 were getting better. Among the 18 feeling stable, 6 belonged to the afflicted, and 12to the nonafflicted group (p < .05).

It could be expected that persons rating their well-being high would not tend to expect further improvement, but this was not the case among the afflicted persons,7 of 11 afflicted persons (p < .07) above the median in well-being expected further improvement. Table 4 shows this distribution. There were no significant correlations between being stable or getting better/worse, and attribution to sources.

TABLE 3. Number of Afflicted Persons Who Underwent Amalgam Sanitation and Their Attribution to Causes

Attribution Sanitation No Sanitation

Had symptoms before trying to find out the cause or were unclear about cause 8 1

Debuted in front of VDU 2 8

TABLE 4. Number of Persons Above the Median of Well-Being Saying They Were Getting Better or Were Stable

Changing/Stable Afflicted Nonafflicted

Getting better 7 2

Stable 4 7

Because afflicted persons introduced many changes in their environment at work and at home, and because electric sanitation had been undertaken in various degrees before the start of this project, changes in the environment were not easily con-

trolled, but subjective exposure judgments from the interviews were classified in lowered exposure (1) or not (0). The expert on electromagnetic measurements (Y. Hamnerius) was asked to estimate the electromagnetic environment of the work stations into lower fields (1) and no change (0) before having any knowledge of my results. These judgments were correlated with health improvement measurements, and the outcome is seen in Table 5. Improvement measurements used were a retrospective question on well-being for the last 18 months, the question of getting better (improving) or getting worse, and the difference between interviews I and II in the num ber of symptoms on the questionnaire. Correlations (rho and phi) show that the classification made by the expert correlates with a reduced number of symptoms. It is further seen in Table 5 that the subjective judgments of well-being, getting better and exposure intercorrelate. When the relatively objective expert estimate of exposure is combined with the subjective exposure estimate, the partial correlations with improvement measures seen in the right-hand column in Table 5 are highly significant.

“HYPERSENSITIVITY TO ELECTRICITY”; SYMPTOMS AND IMPROVEMENT 137

TABLE 5. Correlations Between Estimates

Judgments of Electric Exposure and improvement

EstimatesCorrelates

Ae Asj Ai GellingBetter

Ae-Asj

Expert estimate; Ae _Subjective exposure judgments; Asj 0 . 1 0 —

Improvement in 18 months; Ai Getting betterChange of number of symptoms; As

0.190 . 1 1

0.58

0.570 . 6 6

0.260.620.46 0.29

0.590.830.75

Note. Significances are underlined; levels are (n = 1 9 ): r > .46 for p < .05 and r > .61 for p < .0 1

At the end of Interview I participants were asked to specify any medicine, vitamins, or other additives to food from health shops they took. Among the 23 afflicted persons answering that question, five had medicine (two for allergy, and one for struma, migraine, and estrogen deficit, respectively). Eleven persons among the nonafflicted had one or two prescribed medicines. The difference is significant (p < .05) and if the frequency of estrogen replacement is compared between females exclusively, the difference is again significant. On the other hand, 11 afflicted persons took antioxidants and other food additives, but only 4 nonafflicted. Also this latter difference tends to be significant (p < .06), and the use of these additives among nonafflicted was at a normal level for Swedes.

4. SUMMARY OF RESULTS AND CONCLUSIONS

One group of afflicted persons and one risk group took part in this study and were interviewed twice. The groups were comparable, with the exception of gender: There were m ore women in the group of the nonafflicted. This difference probably m ade


the number of symptoms in the groups more alike—but even so there were still more symptoms in the group of the afflicted at the start of the project. Differences in work organization and environment were few and of the kind that they were m ost likely caused by concern with electrosensitivity, rather than themselves a cause to electrosensitivity. W hen persons claim electrosensitivity it may be fruitless to discuss the amount of exposure in relation to exposure of the nonafflicted, as the concept comprises an extraordinary sensitivity. Afflicted persons indicated that their m anagem ent were relatively familiar with their work tasks. This involvement could have had a positive effect on recovery—but this does not necessarily imply that there had beena strained relation earlier.

Among the symptoms in the questionnaire, redness and pricking sensation in the face were the m ost discernible, and they were still present at the end of the study. These skin reactions tend to be persistent, as mentioned in the introduction, and afflicted persons learned to avoid provoking situations rather than gain improved tolerance. It is understandable that persons experiencing facial skin problems attribute these to the computer that they sit facing for several hours each day. The fact that only half of the participants had these m ost discernible symptoms, gives rise to the question of which half of the persons were the m ost or the least typical electrosensitive participants. Persons with no skin symptoms had no other discernible reactions. N or was it predictable for electrosensitive persons to report redness as well as pricking sensations; they could have one of the symptoms or both. Attempts at creating subgroups of electro sensitive persons are not motivated by the present observations, where symptoms of afflicted persons varied considerably.

The afflicted persons improved from the first to the second interview. The improvement came from symptoms other than the skin symptoms, mainly neuropsychiatric. Perhaps neuropsychiatric symptoms should be regarded as intensifiers, rather than primary symptoms, at least among women men do not report them to any considerable extent. Also, afflicted persons rated their general well-being as high as the nonafflicted did at the time of the second interview. H eartburn and muscular pain coincided with low ratings of wellbeing, not electrosensitivity.

There were high correlations between improvement measurements and judgments of lowered exposure. Afflicted persons remained true to the original idea that their condition was influenced by electric equipment. Persons experiencing reduction of symptoms may see their environment as improved. It is also possible that lower exposure or knowledge of lower exposure has a positive effect on afflicted persons’ well-being. It further seemed as if some of them expected to become perfectly healthy, if only the environment could be perfectly adjusted.

We do not know what information brought the afflicted persons to their standpoint to begin with, but the finding that they consumed significantly less prescribed medicine and more health foods points to a general attribution to the environment. The afflicted persons in this study wanted modifications to be made in their environment, rather than to themselves. Psychological explanations to electrosensitivity, which were given priority to by the National Board of Health and W elfare (1995), focus on the individual. The popularity of environmental factors will keep alive the question of whether the individual or the environment should be corrected, and time might work for the environmental factors.

“ HYPERSENSITIVITY TO ELECTRICITY”; SYMPTOMS AND IMPROVEMENT 139

Arnetz et al. (1995) stated that electrosensitive persons frequently modify the environment themselves. That is why measures taken in (controlled) studies must be interpreted as only one of many sources of observed recovery to health. Answers from nonafflicted persons in this study showed that there were disturbing effects from computers, and the new generation of computers with hard drives and fans are too often noisy and probably generate more heat than the previous generation. The afflicted persons opened windows, turned off computers, or limited time at the computers, thus counteracting the negative effects indicated by the nonafflicted. A part from pricking sensations and redness, the afflicted and nonafflicted showed the same profile of symptoms, though the afflicted had the symptoms more often. This could indicate that many of the symptoms observed here can be related to the office environment or the middle aged participant, and may not be of any explanatory interest in the context of electrosensitivity.

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6 Also available at the Swedish National Library for Working Life.

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