Study type: Medical/biological study (experimental study)

Effect of short-term mobile phone base station exposure on cognitive performance, body temperature, heart rate and blood pressure of Malaysians. med./bio.

Published in: Sci Rep 2015; 5: 13206

Aim of study (acc. to author)

The effects of exposure to a 945 MHz (GSM 900), 1840 MHz (GSM 1800) or a 2140 MHz (UMTS) electromagnetic field on physiological changes and cognitive performance in healthy and electrosensitive subjects should be investigated.

Background/further details

A total of 100 non-electrosensitive subjects and 100 electrosensitive subjects (persons who had previously reported complaints and have attributed these to GSM or UMTS exposure) participated in one session. There, they were exposed to 4 conditions: GSM900, GSM1800, UMTS and sham exposure in a counterbalanced, random order. Each condition was divided into three parts which involved pre-exposure, during exposure, and post-exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 945 MHz
Modulation type: pulsed
Exposure duration: not specified
Exposure 2: 1,840 MHz
Modulation type: pulsed
Exposure duration: not specified
Exposure 3: 2,140 MHz
Exposure duration: not specified

Exposure 1

Main characteristics
Frequency 945 MHz
Type
Exposure duration not specified
Additional info GSM 900 signal
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

signal format consisted of eight time slots; each feature consisted of a duration of 546.5 µsec, leading to a total frame duration of 4.372 msec; the guard time between the time slots of 30.5 µsec was inserted into each GSM frame; to simulate the changes in the power level of channels, time slots of 0, 1, 2, and 3 were set to 'on' (transmitted) whereas the time slots of 4, 5, 6, and 7 are chosen to be 'off'

Exposure setup
Exposure source
Distance between exposed object and exposure source 2 m
Chamber RF shielded room, lined using microwave absorbing sheets; the room was furnished with a wooden table, a flat-screen monitor, a chair and sofa as well as the base station antenna
Setup antenna was placed at 1.5 m from the ground floor
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m - - - power received by each subject
power density 280 W/m² - measured - over the area in which the subject was positioned

Exposure 2

Main characteristics
Frequency 1,840 MHz
Type
Exposure duration not specified
Additional info GSM 1800 signal
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

signal format consisted of eight time slots; each feature consisted of a duration of 546.5 µsec, leading to a total frame duration of 4.372 msec; the guard time between the time slots of 30.5 µsec was inserted into each GSM frame; to simulate the changes in the power level of channels, time slots of 0, 1, 2, and 3 were set to 'on' (transmitted) whereas the time slots of 4, 5, 6, and 7 are chosen to be 'off'

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m - - - power received by each subject
power density 250 W/m² - measured - over the area in which the subject was positioned

Exposure 3

Main characteristics
Frequency 2,140 MHz
Type
Exposure duration not specified
Additional info UMTS signal
Modulation
Modulation type cf. additional info
Additional info

chip rate 3.84 microchips/sec

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m - - - power received by each subject
power density 380 W/m² - measured - over the area in which the subject was positioned

Reference articles

  • Augner C et al. (2010): Effects of Exposure to GSM Mobile Phone Base Station Signals on Salivary Cortisol, Alpha-Amylase, and Immunoglobulin A.
  • Eltiti S et al. (2007): Does short-term exposure to mobile phone base station signals increase symptoms in individuals who report sensitivity to electromagnetic fields? A double-blind randomized provocation study.
  • Regel SJ et al. (2006): UMTS base station-like exposure, well-being, and cognitive performance.
  • Haarala C et al. (2004): 902 MHz mobile phone does not affect short term memory in humans.
  • Haarala C et al. (2003): Effect of a 902 MHz electromagnetic field emitted by mobile phones on human cognitive function: A replication study.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Non-electrosensitive subjects showed a significantly lower heart rate during post-exposure compared to pre-exposure under GSM 900 and GSM 1800 conditions. Under UMTS exposure conditions, both groups, non-electrosensitive and electrosensitive subjects, showed a significant reduction in heart rate during post-exposure compared to pre-exposure.

Study character:

Study funded by

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