Medical/biological study (experimental study)

Effects of microwaves emitted by cellular phones on human slow brain potentials med./bio.

By: Freude G, Ullsperger P, Eggert S, Ruppe I

Published in: Bioelectromagnetics 1998; 19 (6): 384-387

Aim of study (acc. to author)

To study the influence of electromagnetic fields generated by cellular phones on preparatory slow brain potentials (SP), which occur prior to voluntary initiated movements.

Background/further details

The influence of electromagnetic field exposure on SP was investigated in two different experimental tasks: In the first, healthy male subjects had to perform simple self-paced finger movements to elicit a Bereitschaftspotential; in the second, they performed a complex and cognitive visual monitoring task.

Endpoint

effects on the neurological system: EEG (slow brain potentials)

Exposure

- mobile communications
- digital mobile phone
- GSM

Exposure	Parameters
Exposure 1: 916.2 MHz Modulation type: pulsed Exposure duration: continuous for about 3 or 5 min per task	power: 2.8 W peak value power: 350 mW average over time SAR: 1.42 mW/g average over mass (1 g) SAR: 0.882 mW/g average over mass (10 g)

Exposure 1

Main characteristics

Frequency	916.2 MHz
Type	electromagnetic field
Exposure duration	continuous for about 3 or 5 min per task

Modulation

Modulation type	pulsed
Pulse width	577 µs
Repetition frequency	217 Hz
Additional info	no acoustic signal transmission nor power management

Exposure setup

Exposure source	cellular phone with extended antenna
Setup	A digital mobile telephone with extended antenna was positioned in direct contact to the left ear of the subjects. The devices for generating the pulsed electromagnetic energy were operated from a separate room using an extension lead.
Additional info	Tasks were performed with and without EMF exposure single-blind and counterbalanced between subjects.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power	2.8 W	peak value	measured	-	-
power	350 mW	average over time	measured	-	-
SAR	1.42 mW/g	average over mass	measured	1 g	-
SAR	0.882 mW/g	average over mass	measured	10 g	-

Measurement and calculation details

Power was measured using a power meter at the telephone connector. Spatial peak SAR values for the telephone used were assessed in 1996 based on the CENELEC standard with an anatomically realistic full-scaled head phantom.

Exposed system:

human
partial body: left ear

Methods Endpoint/measurement parameters/methodology

effects on the neurological system: EEG (slow brain potentials; mean SP amplitudes); Bereitschaftspotential (self-paced finger movements (to press a mouse key))
cognitive/behavioral endpoints: performance of a visual monitoring task
EOG

Investigated system:

investigation on living organism

Investigated organ system:

brain/CNS

Time of investigation:

during exposure

Main outcome of study (acc. to author)

In the simple finger movement task, no significant electromagnetic field effects on Bereitschaftspotential-parameters were revealed. Although performance parameters in the visual monitoring task did not differ between the exposure and the sham-exposure conditions, slow brain potential parameters show distinct electromagnetic field influence: exposure effected a significant decrease of slow brain potentials at central and temporo-parieto-occipital brain regions, but not at the frontal one.

Study character:

medical/biological study
experimental study
full/main study
Brief Communication

Study funded by

not stated/no funding

Eggert T et al. (2015): Terrestrial Trunked Radio (TETRA) exposure and its impact on slow cortical potentials
Vecchio F et al. (2012): Mobile phone emission increases inter-hemispheric functional coupling of electroencephalographic alpha rhythms in epileptic patients
Vecchio F et al. (2012): Mobile phone emission modulates event-related desynchronization of alpha rhythms and cognitive-motor performance in healthy humans
Kwon MS et al. (2010): No effects of mobile phone use on cortical auditory change-detection in children: an ERP study
Krause CM et al. (2007): Effects of pulsed and continuous wave 902 MHz mobile phone exposure on brain oscillatory activity during cognitive processing
Papageorgiou CC et al. (2006): Acute mobile phone effects on pre-attentive operation
Yuasa K et al. (2006): Effects of thirty minutes mobile phone use on the human sensory cortex
Esen F et al. (2006): Effect of electromagnetic fields emitted by cellular phones on the latency of evoked electrodermal activity
Ferreri F et al. (2006): Mobile phone emissions and human brain excitability
Krause CM et al. (2006): Mobile phone effects on children's event-related oscillatory EEG during an auditory memory task
Hinrichs H et al. (2006): High Frequency GSM-1800 Fields with Various Modulations and Field Strengths: No Short Term Effect on Human Awake EEG
Freude G et al. (2000): Microwaves emitted by cellular telephones affect human slow brain potentials
Petrides M (2000): Exposure to electromagnetic fields by using cellular telephones and its influence on the brain
Krause CM et al. (2000): Effects of electromagnetic fields emitted by cellular phones on the electroencephalogram during a visual working memory task