Non-Specific Health Symptoms

Several groups of investigators have assessed the impact of electromagnetic fields(EMF) on sleep and its disorders, waking electroencephalography (EEG), and theneuroendocrine system. These studies evaluated the effects of both mobile and non-mobile telephone EMF exposure in humans and animals. The results of these studies aresummarized and discussed in this article. 1. Mobile Telephone EMF Exposure 1.1 Effects on Sleep A study by Mann and Röschke (1996) used a 900 MHz GSM cellular telephone signal ata distance of 40 cm to each of 14 subjects (21 34 years) versus an inactive telephonein a randomized cross-over design, studied for 3 consecutive 8-hour nights (1 adaptationnight, 2 experimental nights) in the laboratory. Sleep latency (i.e., the time from lightsout to sleep onset) was significantly reduced from 12.25 to 9.50 minutes with EMFexposure. A non-significant increase was observed in REM sleep latency, but there wasa significant decrease in REM sleep percentages, from 17.07 to 13.91%. In addition,there was an increase of the mean power density in all frequency bands (especially thealpha1, 7.5 12.5 Hz, and alpha2, 12.5 15 Hz, frequency bands), during REM sleep withEMF exposure, while other sleep stages showed a decrease. Subjectively, no significantimpairment of sleep perception was observed.The investigators observed that their experimental approach was limited because EMFinhomogeneities could not be sufficiently controlled and the actual applied EMF powerflux density could only be indirectly measured. To compensate for these limitations,these investigators conducted a follow-up study (Wagner et al., 1998) in which the 900MHz GSM cellular telephone signal was emitted from a circular polarized antenna in asleeping chamber lined with absorbing material custom designed to improve thehomogeneity of the field. Twenty-four healthy male subjects (18 37 years) werestudied in a cross-over design experiment over three consecutive nights, with or without 8hours of EMF exposure. Although there were trends for decreased sleep latencies (15.9± 9.0 to 15.3 ± 7.5 minutes), prolonged REM sleep latencies (60.6 ± 21.5 to 76.0 ± 32.9 INTERNATIONAL WORKSHOP ON ELECTROMAGNETIC FIELDS AND NON-SPECIFIC HEALTHSYMPTOMSGraz, Austria, September 19 20, 1998