27 healthy subjects were studied. For each of them five short EEG epochs (each four minutes; 3.5 minutes break in between) were recorded under exposure. Due to artefacts or vigilance fluctuations, only data from 18 subjects (11 female) were evaluated.
Modulation type: CW
|Exposure 2: 1,800 MHz|
|Exposure 3: 1,800 MHz|
|Exposure 4: 1,800 MHz|
|Exposure 5: 1,800 MHz|
Following a 6-min adaptation period, EEG recordings of 4 min were made for each of six exposure conditions, including sham, that were separated by breaks of 3.5 min. The sequence of conditions was randomised over subjects in double blind mode.
|Distance between exposed object and exposure source||10 mm|
|Chamber||EEG recordings were performed in a separate room, the walls of which were coated with RF-absorbing foam elements with an attenuation of at least 20 dB at 1-2 GHz. The bioamplifier was positioned outside this room.|
|Setup||Subjects were seated in a wooden desk chair in a relaxed wakefulness with eyes closed. The mobile phone was attached to the frame of the chair and was individually positioned with its antenna close to the subject's ear.|
|Sham exposure||A sham exposure was conducted.|
|Additional info||The orientation and position of the antenna approximately matched the 30° position as specified in the measurement standard drafted by CENELEC, SC211/B, WGMTE (1997).|
|Repetition frequency||108 Hz|
|Repetition frequency||27 Hz|
During the four minute exposures under various modulations and field strengths no short-term alterations of the EEG were observed. None of the subjects experienced any remarkable sensations during exposure.
In this study, no evidence for an athermic biological effect of GSM electromagnetic fields on awake EEG was found.