ID Number		1865
Study Type		Human / Provocation
Model		Mobile phone base station exposure and analysis of sleep in local residents
Details		Volunteers (n = 43; 26 women and 17 men) that had attributed their sleep disturbances to local base station emissions were chosen from over 600 respondents to a media request for study participation. The subjects chosen for the study came from multiple regions in Austria and Germany, with final acceptance based on personal conviction on a causal role of EMF &, and with most volunteers reporting more than 5 different subjective health symptoms [associated with EMF exposures]. For the study, a crossover design was employed allowing each subject to serve as his/her own control. Sleep quality was assessed over 10 consecutive nights for each subject in their own home with no shield (control), sham shield, or shielded conditions. The shielding was accomplished by using a blanket of electrically conductive material draped around all sides of the bed, including the bottom. Subjects were reportedly blinded to the shielding conditions in that the sham shield was composed of a material that looked nad felt similar to the shield material but having minimal electric conductivity. However, several individuals during the study were subsequently eliminated for & suspicious openings/closings of the shield material. The ambient RF field was continuously monitored during the night over the frequency range of 80 MHz to 2.5 GHz using a broadband spectral analyzer (Rhode & Schwartz TS-EMF) with the probe element placed above the bed and inside the shielded tent. In addition, temperature, weather conditions, and ELF magnetic fields were recorded throughout the night. Sleep quality was monitored using a polysomnographic system that recorded EEG, EKG, EOG and body position changes. Each morning, a questionnaire of subjective sleep rating was performed. Because of the sequential order of the investigation (each subject studied over 10 consecutive nights), some diurnal variation was unavoidable across the subjects evaluated. RESULTS: For the majority of subjects, no differences in sleep were observed when shielded and sham shielded conditions were compared. In combination with seven additional subjects that only showed a placebo effect (by comparing control vs sham shielded conditions), the authors conclude & the convictions of the overwhelming majority of investigated volunteers (74 %) could not be verified. In three subjects, shielded sleep conditions lead to a significant improvement in subjective sleep parameters, although subsequent checks showed that these same subjects had all examined the shielding material during the night and were thus eliminated as providing biased information. In 6 volunteers, shielded sleep conditions lead to a significant impairment as observed by increased latency across different stages of the sleep cycle. However two of these subjects were also eliminated for providing biased sleep ratings. In the four that remained, the latency from sleep onset to stage 1 was increased on average 4.7 minutes, sleep stage 1 to sleep stage 2 was increased on average 2.3 minutes, and sleep stage 2 to sleep stage 3 was increased on average 8.0 minutes. REM latency was prolonged on average 85.8 minutes. The authors conclude that pooled sleep parameters did not exhibit statistical significant dependencies on RF-EMF emissions, although they point out that the results show & there were responders and non-responders & to the & negative effects (sleep impairment) associated with true-shield condition.
Findings		Effects
Status		Completed With Publication
Principal Investigator		Graz University of Technology, Austria - norbert.leitgeb@tugraz.at
Funding Agency		BfS, Germany, Nat'l Research Prog, Austria
Country		AUSTRIA
References		Leitgeb, N et al. Somnologie , (2008) 12:234-243
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