Medical/biological study (experimental study)

Thermal effects of mobile phones on facial nerves and surrounding soft tissue med./bio.

By: Acar GO, Yener HM, Savrun FK, Kalkan T, Bayrak I, Enver O

Published in: Laryngoscope 2009; 119 (3): 559-562

Aim of study (acc. to author)

To investigate whether mobile phone use might cause temperature rise around the facial nerve and derangement of the nerve function.

Background/further details

12 male rabbits were exposed.

Endpoint

effects on the neurological system: effects on facial nerves and surrounding soft tissue

Exposure

- microwaves
- mobile communications
- mobile phone

Exposure	Parameters
Exposure 1: 1,900 MHz Modulation type: pulsed Exposure duration: continuous for 25 min	power: 1.5 W SAR: 3.72 W/kg

Exposure 1

Main characteristics

Frequency	1,900 MHz
Type	electromagnetic field
Exposure duration	continuous for 25 min

Modulation

Modulation type	pulsed
Repetition frequency	217 Hz

Exposure setup

Exposure source	cellular phone
Distance between exposed object and exposure source	2 mm
Setup	phone held over the rabbit's ear; phone in speaking mode

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power	1.5 W	-	-	-	-
SAR	3.72 W/kg	-	calculated	partial body	-

Exposed system:

animal
rabbit/New Zealand albino
partial body: ear

Methods Endpoint/measurement parameters/methodology

effects on the neurological system: effects on facial nerves: average rate and amplitude of muscle compound action potentials
thermoregulation: effects on the surrounding soft tissue of the facial nerve: temperature change

Investigated system:

investigation on living organism

Investigated organ system:

muscular/skeletal system
autonomic nervous system

Time of investigation:

before exposure
during exposure
after exposure

Main outcome of study (acc. to author)

During the exposure, the average temperature of the surrounding soft tissue was significantly higher (0.39°C) compared to before exposure. After turning off the mobile phone the temperature decreased to pre-exposure values. The average rate of compound action potentials recorded before exposure and after exposure did not differ significantly. The average amplitude of action potentials recorded before exposure was significantly higher than after exposure and went back to normal 25 minutes after exposure.
The temporary temperature rise might have caused temporary facial nerve dysfunction. The authors believe that the observed temperature rise was not due to radiofrequency irradiation, but rather to the battery of the mobile phone or electrical power.

Study character:

medical/biological study
experimental study
full/main study
prospective study

Study funded by

not stated/no funding

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