Study type: Medical/biological study (experimental study)

Mobile phone radiation and the developing brain: behavioral and morphological effects in juvenile rats. med./bio.

Published in: Radiat Res 2007; 168 (4): 471-479

Aim of study (acc. to author)

To evaluate the biological effects of long-term radiofrequency electromagnetic field exposure on the developing brain of rats.

Background/further details

The rats (24 per group) were exposed daily until they were 8 weeks old. At this point six rats of each group were examined histologically to determine possible changes in brain morphology. The remaining 18 rats per group went through a battery of behavioral tests over 4 further weeks.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900 MHz
Modulation type: pulsed
Exposure duration: repeated daily exposure, 2 h/day, 5 days/week, for 5 weeks
  • SAR: 0.3 W/kg mean (whole body) (±30%)
  • SAR: 3 W/kg mean (whole body) (±30%)

Exposure 1

Main characteristics
Frequency 900 MHz
Type
Charakteristic
  • guided field
Exposure duration repeated daily exposure, 2 h/day, 5 days/week, for 5 weeks
Modulation
Modulation type pulsed
Pulse width 0.577 ms
Repetition frequency 217 Hz
Additional info

GSM

Exposure setup
Exposure source
Chamber The exposure system used earlier [Heikkinen et al., 2006] was modified so that it consisted of only three chambers for sham, low dose and high dose exposure. The chambers consisted of two parallel circular aluminium plates (152 cm in diameter and 15 cm apart) short-circuited at the edges with RF-absorbing material attached inside to reduce reflections.
Setup Twenty-four rat cages made of polycarbonate were placed symmetrically around the antenna near the edge of each chamber. The rats could move freely in their cages. Only eight rats (one rat in every third cage) were placed in each chamber, and cylindrical homogeneous flask phantoms (110 ml) were placed in the empty cages.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.3 W/kg mean measured and calculated whole body ±30%
SAR 3 W/kg mean measured and calculated whole body ±30%

Reference articles

  • Heikkinen P et al. (2006): No effects of radiofrequency radiation on 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone-induced tumorigenesis in female Wistar rats.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

No evidence for deleterious effects of GSM-type radiofrequency irradiation in the behavioral or morphological data were found. No degenerative changes, dying neurons, or effects on the blood-brain barrier permeability were detected. No differences were found in the open field test, plus maze test or acoustic startle response tests. The only significant differences between the exposure groups and the sham exposed group were improved learning and memory in the Morris water maze test.

Study character:

Study funded by

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