Sleep Disturbances in the Vicinity of the Short-Wave
Broadcast Transmitter Schwarzenburg
Schlafsto¨rungen in der Umgebung des Kurzwellensenders Schwarzenburg
Theodor Abelin, Ekkehardt Altpeter and Martin Ro¨o¨ sli
Department of Social and Preventive Medicine, University of Berne
[Institut fu¨ r Sozial- und Pra¨ventivmedizin der Universita¨t Bern]
Summary Objectives
The studies reported here investigated the association between health complaints
and the vicinity to the short wave transmitter Schwarzenburg, and looked for evidence for a
relationship between magnetic field exposure and sleep disturbances.
Subjects and Methods Between 1992 and 1998 two cross-sectional and two panel studies
were performed in the area of Schwarzenburg. In each cross-sectional survey about 400
adults living in differently exposed areas were asked about somatic and psycho-vegetative
symptoms including sleep disturbances as well as possible confounding factors. Exposure
was estimated based on 2621 measurements of magnetic field strength made in 56 locations.
In the panel studies, sleep quality and melatonin excretion was studied when the transmission
was interrupted or definitively shut down, respectively.
Results In both surveys, prevalence of difficulties of falling asleep and in particular,
maintaining sleep, increased with increasing radio frequency electromagnetic field exposure
(RF-EMF). Sleep quality improved after interruption of exposure. A chronic change of
melatonin excretion following RF-EMF exposure could not be shown, but a parallel study of
salivary samples in cows showed a temporary increase after a short latency period following
interruption of exposure.
Conclusions The series of studies gives strong evidence of a causal relationship between
operation of a short-wave radio transmitter and sleep disturbances in the surrounding
population, but there is insufficient evidence to distinguish clearly between a biological and a
psychological effect.
Keywords radio frequency - sleep disturbance - insomnia - melatonin - psychovegetative
symptoms - field study - epidemiology
Somnologie 9: 203-209, 2005