Study type: Medical/biological study (experimental study)

Local exposure of 849 MHz and 1763 MHz radiofrequency radiation to mouse heads does not induce cell death or cell proliferation in brain. med./bio.

Published in: Exp Mol Med 2008; 40 (3): 294-303

Aim of study (acc. to author)

To study the effect of local exposure of mobile phone frequency irradiation to the mouse brain for 12 months.

Background/further details

For a long-term exposure experiment the heads of mice (n=120) were irradiated intermittently at 7.8 W/kg. All animals were randomly grouped by radiofrequency exposure types: sham exposure (n=40), 849 MHz (n=40) and 1763 MHz (n=40) with equal numbers of male and female.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 849 MHz
Exposure duration: repeated daily exposure, 1 h/day, 5 days/week, for 6 or 12 months
  • SAR: 7.8 W/kg average over mass (brain)
Exposure 2: 1,762.5 MHz
Exposure duration: repeated daily exposure, 1 h/day, 5 days/week, for 6 or 12 months
  • SAR: 7.8 W/kg average over mass (brain)
  • SAR: 5.28 W/kg average over mass (brain)
  • SAR: 1.55 W/kg average over mass (whole body)

Exposure 1

Main characteristics
Frequency 849 MHz
Type
Exposure duration repeated daily exposure, 1 h/day, 5 days/week, for 6 or 12 months
Modulation
Modulation type cf. additional info
Additional info

CDMA test signal with a nominal bandwidth of 1.23 MHz

Exposure setup
Exposure source
Chamber An aluminium chamber (external size of 745 Π1060 Π1980 mm) lined with RF absorber foam (4.5 in. thick) housed four trays that were stacked on supporters at a vertical spacing of 46 cm.
Setup Each tray held ten ventilated acrylic-tube restrainers (i.d. 34 mm), each loaded head-forward with a mouse. The restrainers were tilted upwards by about 3° (for mouse excretion discharge) and were oriented radially towards a half-wave sleeve dipole antenna at the center of each tray.
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 7.8 W/kg average over mass measured and calculated brain -

Exposure 2

Main characteristics
Frequency 1,762.5 MHz
Type
Exposure duration repeated daily exposure, 1 h/day, 5 days/week, for 6 or 12 months
Additional info PCS channel number 250
Modulation
Modulation type cf. additional info
Additional info

CDMA test signal with a nominal bandwidth of 1.23 MHz

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
SAR 7.8 W/kg average over mass measured and calculated brain -
SAR 5.28 W/kg average over mass calculated brain -
SAR 1.55 W/kg average over mass calculated whole body -

Reference articles

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)

During the 12 months the body weight of the three groups did not show any differences between the groups. The exposure did not change the pattern of neuronal and glia cells in the hippocampus and cerebellum. No evidence of increased cell proliferation or cell death in the radiofrequency exposure groups was found.
The authors conclude that chronic exposure could not induce cellular alterations such as proliferation, cell death (apoptosis) and reactive gliosis.

Study character:

Study funded by

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