Study type: Medical/biological study (experimental study)

Radiofrequency radiation (900 MHz)-induced DNA damage and cell cycle arrest in testicular germ cells in swiss albino mice med./bio.

Published in: Toxicol Ind Health 2017; 33 (4): 373-384

Aim of study (acc. to author)

The effects of exposure of mice to a 900 MHz electromagnetic field (GSM) on the cell cycle and DNA damage in sperms and testes histology should be investigated.

Background/further details

Mice were divided into 5 groups (n=15 each): exposure to the electromagnetic field for 1) 4 h/day for 35 days, 2) 4 h/day for 35 days and subsequent unexposed maintenance for 35 days, 3) 8 h/day for 35 days, 4) 8 h/day for 35 days and subsequent unexposed maintenance for 35 days, 5) control group. Groups 2 and 4 were used to analyze post-exposure recovery effects.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 902.4 MHz
Modulation type: pulsed
Exposure duration: 4 h/day for 35 days
Exposure 2: 902.4 MHz
Modulation type: pulsed
Exposure duration: 8 h/day for 35 days

Exposure 1

Main characteristics
Frequency 902.4 MHz
Type
Exposure duration 4 h/day for 35 days
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

similar to GSM

Exposure setup
Exposure source
Chamber chromium-nickel metal container
Setup animals could move freely during exposure; minimum and maximum distance of animals from antenna was 4.5 cm and 22.5 cm
Parameters
Measurand Value Type Method Mass Remarks
power density 2.717 W/m² maximum measured - at minimum distance of animals to antenna (4.5 cm)
power density 0.284 W/m² minimum measured - at maximum distance of animals to antenna (22.5 cm)
SAR 0.0516 W/kg maximum - - -
SAR 0.0054 W/kg minimum - - -
power 250 mW mean measured - -

Exposure 2

Main characteristics
Frequency 902.4 MHz
Type
Exposure duration 8 h/day for 35 days
Modulation
Modulation type pulsed
Repetition frequency 217 Hz
Additional info

similar to GSM

Exposure setup
Exposure source
Parameters
Measurand Value Type Method Mass Remarks
power density 2.717 W/m² maximum measured - at minimum distance of animals to antenna (4.5 cm)
power density 0.284 W/m² minimum measured - at maximum distance of animals to antenna (22.5 cm)
SAR 0.0516 W/kg maximum - - -
SAR 0.0054 W/kg minimum - - -
power 250 mW mean measured - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

Exposure to the electromagnetic field of groups 3 and 4 caused a significantly reduced mitochondrial membrane potential compared to the control group, though potential was higher after recovery (group 4). Depolarization of the mitochondrial membrane leads to impaired cellular redox homeostasis causing oxidative stress.
The number of abnormal sperm cells with head defects was significantly increased in exposure groups 1, 3 and 4 compared to the control group.
Analysis of germ cell subpopulations in testis showed a significant increase of spermatogonia and a significant decrease in spermatids in groups 3 and 4 compared to the control group. This indicated cell cycle arrest in the pre-meiotic stage of spermatogenesis, which resulted in loss of post-meiotic germ cells.
Histological investigation showed significantly reduced epithelial area and significantly increased loss of tissue in seminiferous tubules in group 3 compared to the control group, but not in group 4. DNA damage was significantly increased in exposure groups 1, 3 and 4 compared to the control group, with most damage found in groups 1 and 3.
The authors conclude that exposure of mice to a 900 MHz electromagnetic field (GSM) might induce oxidative stress, which causes DNA damage that leads to alterations of the cell cycle and to testicular damage. However, these effects might be reversible.

Study character:

Study funded by

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