Study type: Medical/biological study (experimental study)

Effects of gestational exposure to 1.95-GHz W-CDMA signals for IMT-2000 cellular phones: Lack of embryotoxicity and teratogenicity in rats. med./bio.

Published in: Bioelectromagnetics 2009; 30 (3): 205-212

Aim of study (acc. to author)

To study whether gestational exposure to an electromagnetic field targeting the head region, similar to that from cellular phones, might affect embryogenesis in rats.

Background/further details

The gestational period from day 7 to 17 is the most sensitive to developmental toxicologic factors in rats. Pregnant rats (n=20 per group) were studied in this period in four conditions: 1) high exposure, 2) low exposure, 3) control group, 4) sham exposure. All SAR levels were much lower than the level known to cause any thermal stress to pregnant rats or fetuses (in other studies teratogenic effects were evident only when the SAR levels were high enough to raise the maternal body temperature). The experimental design reflected the use of cellular phones by pregnant mothers.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 1.95 GHz
Exposure duration: 90 min/day from day 7 to day 17 of gestation
  • SAR: 0.67 W/kg spatial average (brain) (for the low exposure group)
  • SAR: 3.1 W/kg peak value (brain) (for the low exposure group)
  • SAR: 2 W/kg spatial average (brain) (for the high exposure group)
  • SAR: 7 W/kg peak value (brain) (for the high exposure group)
  • SAR: 0.2 W/kg spatial average (whole body) (for the high exposure group)
  • SAR: 1.5 W/kg spatial average (brain) (for the fetuses in the high exposure group)
  • SAR: 0.11 W/kg spatial average (whole body) (for the fetuses in the high exposure group)

Exposure 1

Main characteristics
Frequency 1.95 GHz
Type
Exposure duration 90 min/day from day 7 to day 17 of gestation
Additional info rats were treated in four groups: i) control ii) low exposure iii) high exposure iv) sham exposure
Exposure setup
Exposure source
  • monopole
Distance between exposed object and exposure source 30 mm
Chamber 90 cm x 90 cm x 60 cm exposure chamber; inside walls except for the ceiling covered with electromagnetic absorbers
Setup rats placed in plastic tubular holders with a diameter of 6.5 cm mounted on a disk-like carrousel with a diameter of 65 cm; noses of the rats directed to the center; resonant 1/4 wavelenght monopole antenna suspended from the ceiling of the chamber
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 0.67 W/kg spatial average calculated brain for the low exposure group
SAR 3.1 W/kg peak value calculated brain for the low exposure group
SAR 2 W/kg spatial average calculated brain for the high exposure group
SAR 7 W/kg peak value calculated brain for the high exposure group
SAR 0.2 W/kg spatial average calculated whole body for the high exposure group
SAR 1.5 W/kg spatial average calculated brain for the fetuses in the high exposure group
SAR 0.11 W/kg spatial average calculated whole body for the fetuses in the high exposure group

Reference articles

  • Wake K et al. (2007): An Exposure System for Long-Term and Large-Scale Animal Bioassay of 1.5-GHz Digital Cellular Phones.
  • Shirai T et al. (2007): Lack of promoting effects of chronic exposure to 1.95-GHz W-CDMA signals for IMT-2000 cellular system on development of N-ethylnitrosourea-induced central nervous system tumors in F344 rats.

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

There were no differences in maternal body weight gain in all groups. No adverse effects of electromagnetic field exposure were observed on any reproductive and embryo-toxic parameters.
No clear adverse effects of maternal exposure to electromagnetic fields targeting the head area and embryogenesis were demonstrated.

Study character:

Study funded by

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