Study type: Medical/biological study (experimental study)

Lack of adverse effects of whole-body exposure to a mobile telecommunication electromagnetic field on the rat fetus. med./bio.

Published in: Radiat Res 2010; 173 (3): 362-372

Aim of study (acc. to author)

To evaluate the potential adverse effects of long-term whole body exposure to electromagnetic field signals from a base station for cell phone communication during the gestation and lactation periods of rats.

Background/further details

Three identical independent experiments were performed with a total of 36 rats. For each experiment, 12 pregnant rats were divided into three groups of four rats each: Group 1 received sham exposure, and groups 2 and 3 were exposed to electromagnetic fields at low and high levels, respectively. Four days after delivery, eight F1 rats per dam (four males and four females) were also selected for continuous exposure until age of 21 days.
Exposure of the 10-week-old pregnant rats was started at gestational day 7 and continued for 20 h per day until weaning of F1 rats.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 2.14 GHz
Exposure duration: continuous for 20 hr/day from day 7 of gestation until weaning of F1 rats
  • power: 0.818 W
  • SAR: 0.04 W/kg maximum (whole body) (for the dams)
  • SAR: 0.06 W/kg maximum (whole body) (for the fetus)
Exposure 2: 2.14 GHz
Exposure duration: continuous for 20 hr/day from day 7 of gestation until weaning of F1 rats
  • power: 1.898 W
  • SAR: 0.09 W/kg maximum (whole body) (for the dams)
  • SAR: 0.16 W/kg maximum (whole body) (for the fetus)

Exposure 1

Main characteristics
Frequency 2.14 GHz
Type
Exposure duration continuous for 20 hr/day from day 7 of gestation until weaning of F1 rats
Additional info W-CDMA downlink signal simulated
Exposure setup
Exposure source
Setup 90 cm x 90 cm x 60 cm exposure boxes, covered on the inside with 6 cm thick planar RF absorbers except for the ceiling, which was made of metal mesh; animals placed in individual 690.8 mm² acrylic cages inside the exposure boxes
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power 0.818 W - - - -
SAR 0.04 W/kg maximum - whole body for the dams
SAR 0.06 W/kg maximum - whole body for the fetus

Exposure 2

Main characteristics
Frequency 2.14 GHz
Type
Exposure duration continuous for 20 hr/day from day 7 of gestation until weaning of F1 rats
Additional info W-CDMA downlink signal simulated
Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power 1.898 W - - - -
SAR 0.09 W/kg maximum - whole body for the dams
SAR 0.16 W/kg maximum - whole body for the fetus

Reference articles

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

Main outcome of study (acc. to author)

Overall, the data did not reveal any adverse effects of exposure to a 2.14 GHz W-CDMA signal for 20 h/day. The value of the present negative results, however, could be limited by the lack of a positive control.
The findings did demonstrate some statistically significant differences between the sham exposure group and the exposure groups. For example, the body weights of exposed males were increased. However, such changes were transient and were not considered to be due to the exposure. Among seven physiological development indicators, delay of pinna unfolding was found in the high exposure group at day 2 but not at day 3. Furthermore, while the number of corpora lutea in the pregnant F1 females was found to be decreased in the low exposure group, a decrease was not present in the high exposure group.
Thus none of the experimental findings demonstrated any consistent adverse biological effects of whole body exposure to the electromagnetic field on gestation and lactation in either dams or F1 rats or in the F2 offspring under these experimental conditions.

Study character:

Study funded by

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