Study type: Medical/biological study (experimental study)

Effects of Global Communication system radio-frequency fields on Well Being and Cognitive Functions of human subjects with and without subjective complaints. med./bio.

Published in: TNO Reports 2003; (FEL03C148): 1-89
Journal not peer-reviewed

Aim of study (acc. to author)

To study general symptoms and cognitive functions with and without exposure to GSM and UMTS-like fields in subjects presenting with complaints subjectively attributed to GSM fields.

Background/further details

This study is the so-called TNO study.
72 subjects (36 self-reported electrosensitive, 36 non-electrosensitive subjects) participated.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 945 MHz
Modulation type: pulsed
Exposure duration: continuous for 20 min
Exposure 2: 1,840 MHz
Modulation type: pulsed
Exposure duration: continuous for 20 min
Exposure 3: 2,140 MHz
Exposure duration: continuous for 20 min

General information

The design of the study was a completely balanced double-blind randomized three-way crossover evaluation where study subjects were allocated to exposure sessions according to a balanced block randomization (for both groups, 18 blocks of 2 subjects each) taking into account all exposure sequences. After a first training session, each subject participated in three consecutive experimental sessions with one sham (in any case) and two different RF exposures to 900, 1800, or 2100 MHz EMF.

Exposure 1

Main characteristics
Frequency 945 MHz
Type
Charakteristic
Exposure duration continuous for 20 min
Modulation
Modulation type pulsed
Pulse width 577 µs
Repetition frequency 217 Hz
Additional info

GSM signal with time slots 0-3 on and 4-7 off resulting in an overall duty cycle of 50%

Exposure setup
Exposure source
Distance between exposed object and exposure source 3 m
Chamber Two antennas were placed on a tripod, one antenna transmitting UMTS-like fields while the other was a dual band antenna transmitting GSM 900 MHz as well as DCS 1800 MHz fields. The amplifier and antenna combination was selected by a coaxial switch box.
Setup The subjects were seated at a desk with their right (?) side turned to the antennas that were at a distance of 3 m from the body axis with their centre at a height of 1.5 m.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m peak value measured - -
electric field strength 0.71 V/m effective value measured - -
SAR 0.045 mW/kg maximum calculated 10 g -
SAR 0.000513 µW/kg average over mass calculated partial body -

Exposure 2

Main characteristics
Frequency 1,840 MHz
Type
Charakteristic
Exposure duration continuous for 20 min
Modulation
Modulation type pulsed
Pulse width 577 µs
Repetition frequency 217 Hz
Additional info

GSM signal with time slots 0-3 on and 4-7 off resulting in an overall duty cycle of 50%

Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m peak value measured - -
electric field strength 0.71 V/m effective value measured - -
SAR 0.082 mW/kg maximum calculated 10 g -
SAR 0.000383 µW/kg average over mass calculated partial body -

Exposure 3

Main characteristics
Frequency 2,140 MHz
Type
Charakteristic
Exposure duration continuous for 20 min
Modulation
Modulation type cf. additional info
Additional info

The UMTS signal simulated the downlink settings of a base station with the following frames transmitted: P-SCH, S-SCH, P-CCPCH and CPICH. The chiprate (clock frequency) was 3.84 MHz.

Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
electric field strength 1 V/m peak value measured - -
electric field strength 1 V/m effective value measured - -
SAR 0.078 mW/kg maximum calculated 10 g -
SAR 0.064 mW/kg maximum calculated 10 g front illumination
SAR 0.000316 µW/kg average over mass calculated partial body -
SAR 0.000327 µW/kg average over mass calculated partial body front illumination

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

A statistically significant relation between UMTS-like fields with a field strength of 1 V/m and an effect on the well-being was found (lower overall well-being). Further, a number of significant effects was revealed in the cognitive tasks.

Study character:

Study funded by

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