Study type: Medical/biological study (experimental study)

Effects of intrauterine and extrauterine exposure to GSM-like radiofrequency on distortion product otoacoustic emissions in infant male rabbits. med./bio.

Published in: Int J Pediatr Otorhinolaryngol 2009; 73 (3): 391-399

Aim of study (acc. to author)

To investigate the potential hazadous effects of intrauterine and/ or extrauterine GSM radiofrequency exposure on the cochlear functions of infant rabbits.

Background/further details

36 male rabbits were randomly divided into four groups (each n=9): 1) control group; 2) extrauterine exposure (at 1 month of age); 3) intrauterine exposure (between 15th and 22nd days of the gestational period); and 4) both intrauterine and extrauterine exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1,800 MHz
Modulation type: pulsed
Exposure duration: 15 min/day for 14 days from 1 month of age
Exposure 2: 1,800 MHz
Modulation type: pulsed
Exposure duration: 15 min/day for 7 days between 15th and 22nd day of gestation
Exposure 3: 1,800 MHz
Modulation type: pulsed
Exposure duration: 15 min/day for 7 days between 15th and 22nd day of gestation + 15 min/day for 14 days from 1 month of age

Exposure 1

Main characteristics
Frequency 1,800 MHz
Type
Exposure duration 15 min/day for 14 days from 1 month of age
Modulation
Modulation type pulsed
Pulse width 0.576 ms
Duty cycle 12.5 %
Repetition frequency 217 Hz
Pulse type rectangular
Exposure setup
Exposure source
Chamber shielded room
Parameters
Measurand Value Type Method Mass Remarks
power 0.1 W - measured - -

Exposure 2

Main characteristics
Frequency 1,800 MHz
Type
Exposure duration 15 min/day for 7 days between 15th and 22nd day of gestation
Modulation
Modulation type pulsed
Pulse width 0.576 ms
Duty cycle 12.5 %
Repetition frequency 217 Hz
Pulse type rectangular
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
power 0.1 W - measured - -

Exposure 3

Main characteristics
Frequency 1,800 MHz
Type
Exposure duration 15 min/day for 7 days between 15th and 22nd day of gestation + 15 min/day for 14 days from 1 month of age
Modulation
Modulation type pulsed
Pulse width 0.576 ms
Duty cycle 12.5 %
Repetition frequency 217 Hz
Pulse type rectangular
Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
power 0.1 W - measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

No significant differences in the mean distortion product otoacoustic emissions were found among the four groups at 1.0 an 8.0 kHz. For the other frequencies significant group differences were present: Harmful effects were mainly observed during extrauterine exposure: the amplitudes at 4.0 and 6.0 kHz were reduced, showing a decrease in the cochlear activity. After the intrauterine exposure the amplitudes were increased at 1.5-6.0 kHz.
The authors conclude that prolonged exposure and hyperthermia related to the power density increased the temperature in the ear canal and may affect the distortion product otoacoustic emissions response amplitudes during the extrauterine exposure. During the intrauterine exposure, water and amnion fluid in the middle ear may have a protective role.

Study character:

Study funded by

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