Study type: Medical/biological study (experimental study)

Effect of mobile phone radiation on pentylenetetrazole-induced seizure threshold in mice. med./bio.

Published in: Iran J Basic Med Sci 2016; 19 (7): 800-803

Aim of study (acc. to author)

The effects of acute and chronic exposures of mice to a 900-950 MHz electromagnetic field (GSM) on the risk for epileptic seizures should be investigated.

Background/further details

To induce epileptic seizure in the animal model, intravenous pentylenetetrazole infusion was used (5 mg/ml and 0.3 ml/min (remark EMF-Portal: or 0.5 ml/min? contradictory statements)). Each animal was observed throughout the infusion period and the duration between the start of infusion and onset of seizure stages was recorded and then converted to the threshold seizure dosage (i.e. mg of drug per kg of body weight). Sudden involuntary muscle jerk followed by rapid writhing movements of the head and neck and/or clonic movements of forelimbs were considered as the signs of clonic seizure, and spasmodic hind limb extension, extreme rigidity with forelimbs, and hindlimbs extended caudally were considered as the signs of tonic seizure, i.e. a seizure in which the musculature affected is permanently strongly tensed.
Male mice were divided into 7 groups (with at least n=8 animals per group): 1) acute exposure for 30 minutes, 2) acute exposure for 60 minutes, 3) acute exposure for 90 minutes, 4) chronic exposure for 30 minutes per day for 30 days, 5) chronic exposure for 60 minutes per day for 30 days, 6) chronic exposure for 90 minutes per day for 30 days, 7) control group (remark EMF-Portal: treatment of the control group and the chronology of exposures and epileptic seizure induction remain unclear).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900–950 MHz
Modulation type: pulsed
Exposure duration: continuous for 30 minutes
-
Exposure 2: 900–950 MHz
Modulation type: pulsed
Exposure duration: continuous for 60 minutes
-
Exposure 3: 900–950 MHz
Modulation type: pulsed
Exposure duration: continuous for 90 minutes
-
Exposure 4: 900–950 MHz
Modulation type: pulsed
Exposure duration: intermittent for 30 minutes/day for 30 days
-
Exposure 5: 900–950 MHz
Modulation type: pulsed
Exposure duration: intermittent for 60 minutes/day for 30 days
-
Exposure 6: 900–950 MHz
Modulation type: pulsed
Exposure duration: intermittent for 90 minutes/day for 30 days
-

Exposure 1

Main characteristics
Frequency 900–950 MHz
Type
Exposure duration continuous for 30 minutes
Additional info acute exposure
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Chamber plastic cages (45 cm diameter, 11 cm height) (remark EMF-Portal: it is not clear how many animals were exposed simultaneously)
Setup cell phone in answering mode was positioned in a way that the maximum distance to the animals was about 10 cm
Parameters

No parameters are specified for this exposure.

Exposure 2

Main characteristics
Frequency 900–950 MHz
Type
Exposure duration continuous for 60 minutes
Additional info acute exposure
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Parameters

No parameters are specified for this exposure.

Exposure 3

Main characteristics
Frequency 900–950 MHz
Type
Exposure duration continuous for 90 minutes
Additional info acute exposure
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Parameters

No parameters are specified for this exposure.

Exposure 4

Main characteristics
Frequency 900–950 MHz
Type
Exposure duration intermittent for 30 minutes/day for 30 days
Additional info chronic exposure
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Parameters

No parameters are specified for this exposure.

Exposure 5

Main characteristics
Frequency 900–950 MHz
Type
Exposure duration intermittent for 60 minutes/day for 30 days
Additional info chronic exposure
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Parameters

No parameters are specified for this exposure.

Exposure 6

Main characteristics
Frequency 900–950 MHz
Type
Exposure duration intermittent for 90 minutes/day for 30 days
Additional info chronic exposure
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Parameters

No parameters are specified for this exposure.

Reference articles

  • Lopez-Martin E et al. (2009): The action of pulse-modulated GSM radiation increases regional changes in brain activity and c-Fos expression in cortical and subcortical areas in a rat model of picrotoxin-induced seizure proneness.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Animals with chronic exposures to the electromagnetic field (groups 4-6) showed significantly lower threshold doses for tonic and clonic seizures compared to the control group and exposures for 60 and 90 minutes per day (groups 5 and 6) showed significantly lower values than exposure for 30 minutes per day (group 4).
Animals with acute exposures to the electromagnetic field (groups 1-3) did not show any significant differences compared to the control group.
The authors conclude that chronic exposure of mice to a 900-950 MHz electromagnetic field (GSM) might increase the risk for epileptic seizures.

Study character:

Study funded by

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