Study type: Medical/biological study (experimental study)

Mobile telephone use effects on perception of verticality. med./bio.

Published in: Bioelectromagnetics 2015; 36 (1): 27-34

Aim of study (acc. to author)

The effects of an acute ear exposure of human probands to an 882 MHz electromagnetic field from a mobile phone on graviperception should be investigated.

Background/further details

In the first part of the study, electrosensitive probands (cases, n=9) were compared with persons without subjective complaints (control, n=21). First, all probands were examined without exposure to determine the baseline. Afterwards, each proband was exposed to a continuous signal (CW), pulsed signal (GSM) and sham exposure in random order by strapping a mobile phone to the right and left ear, respectively. This part was conducted on the same day, with the same probands and same exposure conditions as Bamiou et al. 2008. However, the results of the first test indicated an effect of the pure weight of the mobile phone on graviperception. This was checked in a second experiment with solely probands without complaints (n=18) using a turned-off mobile phone.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 882 Hz
Modulation type: CW
Exposure duration: continuous for 2 x 30 minutes (30 minutes per ear)
  • SAR: 1.3 W/kg maximum (10 g) (at antenna, ± 30%)
  • SAR: 0.3 W/kg cf. remarks (10 g) (at mobile body)
Exposure 2: 882 Hz
Modulation type: pulsed
Exposure duration: continuous for 2 x 30 minutes (30 minutes per ear)
  • SAR: 0.3 W/kg cf. remarks (10 g) (typical value at mobile body)
  • SAR: 1.3 W/kg maximum (10 g) (at antenna, ± 30%)

Exposure 1

Main characteristics
Frequency 882 Hz
Type
Exposure duration continuous for 2 x 30 minutes (30 minutes per ear)
Modulation
Modulation type CW
Exposure setup
Exposure source
Chamber probands were seated on a chair with chin rest in a dark room in front of the test display
Setup exposure system consisted of a headband mounted mobile phone that could emit GSM-modulated signals (GSM-mode) and signals without modulation (continuous signal) with the same mean power and heating of less than 1°C in each mode; mobile phone could be adjusted in either right- or left-handed positions against the head in a geometry simulating a call
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 1.3 W/kg maximum measured 10 g at antenna, ± 30%
SAR 0.3 W/kg cf. remarks measured 10 g at mobile body

Exposure 2

Main characteristics
Frequency 882 Hz
Type
Exposure duration continuous for 2 x 30 minutes (30 minutes per ear)
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.3 W/kg cf. remarks measured 10 g typical value at mobile body
SAR 1.3 W/kg maximum measured 10 g at antenna, ± 30%

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • before exposure
  • during exposure

Main outcome of study (acc. to author)

In the first part of the study, no significant differences could be found either between control group and case group (electrosensitive probands) under the different conditions of exposure or between the different exposure conditions and the baseline within each group. However, a significant difference from the baseline depending on the side of the strapped mobile phone was found in all groups and under all conditions of exposure. In the second part of the study, the significant effect of the strapping side of the mobile phone on the test outcome was verified.
The authors conclude that an ear exposure to a 882 MHz electromagnetic field from a mobile phone has probably no effects on graviperception. However, the weight of the mobile phone, which was strapped to either one side of the head in the experiment, can influence the perception of verticality.

Study character:

Study funded by

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