To evaluate whether different intensities of radiofrequency electromagnetic field exposure from an operating mobile phone GSM-signal base station with only short-term exposure can cause detectable differences in subjective well-being. Secondary it was investigated whether symptoms could be shown to be associated with a "nocebo" effect caused by anxiety, concerns and stress.
57 participants (35 women) were randomly assigned to one of three different exposure scenarios with three exposure levels (low, medium, high). Hypersensitive individuals were neither actively recruited, nor excluded from the tests.
Modulation type: pulsed
Exposure duration: intermittent, 5 x 50 min, with 5-min breaks
|Exposure duration||intermittent, 5 x 50 min, with 5-min breaks|
|Distance between exposed object and exposure source||6 m|
|Chamber||The experiments took place in an adapted room in a kindergarten. Participants sat on a comfortable wooden chair at 6 m from the GSM-900 omni antenna mounted on the facade of the building and behind a gap in the shielding carbonaceous wall paint.|
|Setup||Three different exposure levels (low, medium, and high) were created by shielding and placebo curtains which could be installed or removed by technicians during the 5-min breaks between sessions such that double-blinded conditions prevailed.|
|Additional info||Participants were randomly subjected to one of three different exposure scenarios with five 50-min exposure sessions of which only the first four were relevant for the study of psychological symptoms. The scenarios were HM: LHLML, MH: LMLHL, and LL: LLLLH. Due to early termination of the study, numbers of subjects for the three scenarios were not equal as projected (22 for HM, 26 for MH, and 9 for LL).|
|power density||5.2 µW/m²||mean||measured||-||Low|
|power density||153.6 µW/m²||mean||measured||-||Medium|
|power density||2,126.8 µW/m²||mean||measured||-||High|
Participants that received high or medium exposure were significantly calmer during the sessions than participants in the low exposure condition. No significant differences between the different intensities on the parameters "good mood" or "alertness" were found. Self-rated electromagnetic hypersensitivity was low in prevalence and did not correlate with any of the factors describing psychological stress.
The authors conclude that short-term exposure to GSM base station signals may have an impact on well-being by reducing psychological arousal.