Electrohypersensitivity a moving target from VDT to WiFi

Transcription

1 Electrohypersensitivity a moving target from VDT to WiFi Kjell Hansson Mild 1 and Monica Sandström 2 1. Dept. of Radiation Sciences, 2. Dept. of Occup. and Environ. Medicine, Umeå University, Umeå, Sweden kjell.hansson.mild@radfys.umu.se

2 Already in the 1980s VDT related skin rashes were reported, UK, Norway, Sweden. (VDT: static E field = screens, magnetic field from coils pregnancy questions, etc) From the 90s patients also started to complain about problem with other electrical equipment and the term electromagnetic hypersensitivty was introduced since EMF was the only common factor. Since the 90s many people experienced symptoms while using mobile phones.

3 WHO 2004 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 as well as neurasthenic and vegetative symptoms The collection of symptoms is not part of any recognized syndrome. *Other terms: electrohypersensitivity, electro-sensitivity, electrical sensitivity, and electrical allergy. Ref: Hansson Mild K, Repacholi M, van Deventer, and P Ravazzani, Eds. Electromagnetic Hypersensitivity. Proceedings from an international workshop on EMF Hypersensitivity, Prague, Czech Republic, Oct 27-27, WHO Library Cataloguing-in-Publication Data, ISBN

4 Internet search for EHS

5 The handicap federation in Sweden

6 Symptoms Skin: - burning sensations - stinging - itching General symptoms: - fatique - general discomfort - headaches Autonomic nervous system: - palpitations - respiratory distress - sleep disturbances Cognition: - concentration problems - memory loss

7 What causes the symptoms? Video display screens Office machines Electric equipment Fluorescent tubes Power lines Mobile phones Base stations

8 Heterogeneous group! Large variation in symptoms The same sources give different symptoms One/a few/many sources give symptoms Varying severity of handicap The progression differs: (better/worse/no change) Different results of measures No uniform picture!

9 Research? Epidemiology (environment, ind. factors) Medical examinations (case reports) Follow-up studies of measures and treatment Provocation studies

10 Why provocation studies? Causal connection between agents and biological response How to measure the response? Provocation with known factors known response

11 Neurophysiological effects of flickering light in patients with perceived electrical hypersensitivity. M. Sandström, E. Lyskov, A. Berglund, S. Medevedev, K. Hansson Mild: JOEM. 1997, 39: Neurophysiological study of patients with perceived electrical hypersensitivity. E. Lyskov, M. Sandström, K. Hansson Mild. Int J of Psychophysiology. 2001,42: Provocation study of persons with perceived electrical hypersensitivity and controls using magnetic field exposure and recording of electrophysiological characteristics. E. Lyskov, M. Sandström, K. Hansson Mild. Bioelectromagnetics. 2001, 22: Holter ECG monitoring in patients with perceived electrical hypersensitivity. Sandström M, Lyskov E, Hansson Mild K, et al Int J Psychophysiol Sep;49(3):

12 Provoking factor response Basic condition Flickering light Sound EEG, CFF SSR, SSR latency, HR, HRV External load Mental load Physical load Magnetic field

13 Exposure set up

14 Flickering light sources

15 Fluorescent Compact low VDT light tube energy lamp M. Sandström

16 20 Hz 55 Hz VEP Amplitude (µv) 5 µv VEP Amplitude (µv) Time (ms) 25 Hz Time (ms) 65 Hz 100 VEP Amplitude (µv) VEP Amplitude (µv) 5 µv Time (ms) 45 Hz Time (ms) 75 Hz 100 VEP Amplitude (µv) VEP Amplitude (µv) 0 50 Time (ms) Time (ms) 60

17 Stimuli Study 1 Flickering light Study 2 Study 3 Flickering light Noise Mental load Physical load Flickering light Noise Mental load Physical load Magnetic field

18 In summary Hyperreactivity to external factors Increased sympathetic activity Higher CFF Heterogeneous group No connection with magnetic field exposure

19 Test person with equipment for HRV and MF registration

20 HR EHS CONTROLS Figure hour registration of heart rate (mean values for each hour) from EHS and controls. In bars the 95% confidence intervals are shown.

21 HFn (%) Controls EHS EHSCONTROLS Figure hour registration of normalized HF (mean values for each hour) from EHS and controls. In bars the 95% confidence intervals are shown

22 Conclusion of the HRV study a disturbance of the circadian rhythms of the autonomous regulation significantly less parasympathetic activity during sleep

23 Among EHS patients we found: Hyperreactivity to external factors Increased sympathetic activity Higher CFF Significantly less parasympathetic activity during sleep

24 Observed deviations in EHS references Higher HR Wang et al (1994) Lyskov et al (2001) Higher diast. blood pressure Lyskov et al (2001) Divergent temp. increase left/right Wennberg et al (1994) Divergent pupill reaction Rea et al (1991) Wang et al (1994) Higher amplitude in Visual Evoked Potential after light stimulus Sandström et al (1997) Lyskov et al (2001)

25 Johansson A, Nordin S, Heiden M, Sandström M. Symptoms, personality traits, and stress in people with mobile phone-related symptoms and electromagnetic hypersensitivity. J Psychosom Res (1): The EHS group reported more symptoms than the MP group, both EMF-related and EMF-nonrelated. The MP group reported a high prevalence of somatosensory symptoms, whereas the EHS group reported more neurasthenic symptoms. Nordin S, Neely G, Olsson D, Sandström M. Odor and noise intolerance in persons with self-reported electromagnetic hypersensitivity. Int J Environ Res Public Health (9): The findings suggest an association between EHS and odor and noise intolerance

26 MP related Warmth behind/around ear Tingling sensation VDT related Skin symptoms: stinging, itching, burning rosacea Electric equipment related Fatigue, headache, dizziness, concentration difficulties, cardiovascular symptoms

27 Summary of several studies on EHS Hyperreaktivity to external factors Higher CFF Unbalance in ANS Heterogenous grupp Clinically applicable

28 EHS: Previously known as Da Costas syndrome?? Symptoms of Da Costa's syndrome include fatigue upon exertion, shortness of breath, palpitations, sweating, and chest pain. Physical examination reveals no physical abnormalities causing the symptoms. [9]