Medical/biological study (experimental study)

Intraoperative observation of changes in cochlear nerve action potentials during exposure to electromagnetic fields generated by mobile phones med./bio.

By: Colletti V, Mandala M, Manganotti P, Ramat S, Sacchetto L, Colletti L

Published in: J Neurol Neurosurg Psychiatry 2011; 82 (7): 766-771

Aim of study (acc. to author)

To study whether exposure to mobile phone electromagnetic fields affect acoustically evoked cochlear nerve compound action potentials.

Background/further details

Seven patients suffering from Meniere's disease and undergoing retrosigmoid vestibular neurectomy were exposed to the mobile phone placed over the craniotomy area for 5 minutes. Five patients undergoing the same surgical procedure served as control group.

Endpoint

effects on auditory system: cochlear nerve bioelectrical activity

Exposure

- mobile communications
- mobile phone

Exposure	Parameters
Exposure 1: 900 MHz Exposure duration: continuous for 5 min (active call)	SAR: 0.82 W/kg maximum

Exposure 1

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Exposure duration	continuous for 5 min (active call)

Exposure setup

Exposure source	Nokia 6310i mobile phone
Distance between exposed object and exposure source	62 mm
Setup	mobile phone positioned over the craniotomy area; for sham exposure mobile phone in stand-by mode
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
SAR	0.82 W/kg	maximum	-	-	-

Exposed system:

human
partial body: cranium (craniotomy area)

Methods Endpoint/measurement parameters/methodology

effects on auditory system: cochlear nerve bioelectrical activity (acoustically evoked cochlear compound action potentials (amplitude and latency) and acoustic evoked brainstem potentials)

Investigated system:

investigation on living organism

Investigated organ system:

Time of investigation:

before exposure
during exposure
after exposure

Main outcome of study (acc. to author)

All patients showed a substantial significant decrease in amplitude and a significant increase in latency of cochlear nerve compound action potentials during the 5 min of exposure to the electromagnetic field. These changes lasted for a period of around 5 min after exposure. The analysis of the acoustic evoked brainstem potentials performed on wave V showed no statistically significant differences related to the electromagnetic field exposure. Postoperative audiological follow-up revealed no significant hearing threshold deterioration in any of the patients.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

not stated/no funding

Kaprana AE et al. (2011): Auditory brainstem response changes during exposure to GSM-900 radiation: an experimental study
Kwon MS et al. (2010): No effects of mobile phone electromagnetic field on auditory brainstem response
Kwon MS et al. (2010): No effects of mobile phone use on cortical auditory change-detection in children: an ERP study
Parazzini M et al. (2010): Absence of short-term effects of UMTS exposure on the human auditory system
Balbani AP et al. (2008): Mobile phones: influence on auditory and vestibular systems
Paglialonga A et al. (2007): Effects of mobile phone exposure on time frequency fine structure of transiently evoked otoacoustic emissions
Stefanics G et al. (2007): Short GSM mobile phone exposure does not alter human auditory brainstem response
Oysu C et al. (2005): Effects of the acute exposure to the electromagnetic field of mobile phones on human auditory brainstem responses
Kerekhanjanarong V et al. (2005): The effect of mobile phone to audiologic system
Arai N et al. (2003): Thirty minutes mobile phone use has no short-term adverse effects on central auditory pathways