To study the 2.45 GHz low level microwave exposure-induced stress response and its effect on implantation or pregnancy in female mice.
Female mice were divided into two groups (n=6 per group) and exposed or sham exposed for 45 days. After 20 days of exposure, respectively two mice were mated with one male mouse for 5 days (exposure of female mice continued). Afterwards, mice were exposed for another 20 days.
The whole experiment was repeated.
Modulation type: CW
Exposure duration: continuous for 2 h/day on 45 days
|Exposure duration||continuous for 2 h/day on 45 days|
|Distance between exposed object and exposure source||25 cm|
|Setup||10 cm long pyramidal horn antenna (throat and mouth dimensions were 7.2 cm x 3.2 cm and 9 cm x 5 cm) placed above the cage; 19.2 cm x 17.6 cm x 15 cm cage made of pine wood, divided into six 6 cm x 8 cm x 15 cm compartments, each holding one mouse during exposure; 1 cm holes drilled into the sides and partition walls, and upper part of the cage kept open for ventilation; mice restrained in the compartments; upper side of the walls, partition walls and base of the cage covered with carbon-impregnated styrofoam microwave absorbers; cage placed on and covered from all sides with microwave absorbers; cage tied to the absorber unit to avoid a change in position in regard to the antenna|
|Sham exposure||A sham exposure was conducted.|
|power density||0.033549 mW/cm²||-||calculated||-||-|
|SAR||0.023023 W/kg||-||estimated||whole body||-|
In the exposed group, an unequal/asymmetrical distribution of embryos in the two uterine horns and reduced inter-embryo spaces were observed as compared to the control group. Additionally, no pups were born in the exposed group while a normal number of pups was born in the sham exposed group.
It was found that the hemoglobin content as well as the number of erythrocytes and leukocytes and the neutrophil/lymphocyte ratio increased significantly in the exposed group compared to the sham exposed one.
In the comet assay, the brain cells of exposed mice showed a significant increase in the tail moment, in the tail DNA amount and the tail length when compared to control brain cells, i.e. a DNA damage was found in the exposed group.
In the exposed group, a significant decrease in total nitrite and nitrate concentrations was observed in the plasma when compared to the control group.
The levels of estradiol and progesterone in the plasma were increased in the exposed group in comparison to the sham exposed group, but only the value for estradiol was statistically significant.
A significant elevated level of reactive oxygen species in the kidney, liver and ovary was observed in the exposed group as compared to the control group.
Regarding the antioxidant enzyme activities, the activities of the superoxide dismutase, the catalase and the glutathione peroxidase were significantly decreased in the kidney, liver and ovary of the exposed animals in comparison to the sham exposed ones.
The authors conclude that an exposure to low level microwaves (2.45 GHz) could affect the implantation or pregnancy in mice through oxidative stress.