Male 21-day-old rats were divided into 3 groups (n=8 each): 1) exposure to the electromagnetic field, 2) sham exposure and 3) cage control. All rats were killed on postnatal day 60 and hearts were investigated.
Exposure duration: 1 h/day between postnatal days 21 and 59
|Chamber||plexiglass cage (42 cm length x 30 cm width x 50 cm height)|
|Setup||half-wave dipole antenna was made of 1 mm wide x 15 cm long copper plate and was inserted into the central area of the plexiglass cage, approximately 11 cm inside the opening; rats could move freely during exposure; temperature during exposure was 21.43°C ± 1.07°C and humidity was 59.8% ± 4.11%|
|Sham exposure||A sham exposure was conducted.|
|Additional info||all groups were kept in the same room in separate cages under the same environmental conditions, except during sham and EMF exposure; temperature during sham exposure was 21.30°C ± 1.08°C and humidity was 59.7% ± 4.34%|
|power||300 mW||-||-||-||approximate output power|
|electric field strength||7 V/m||mean||measured||-||on the outside the empty plexiglass cage floor|
|electric field strength||9.54 V/m||mean||measured||-||on the inside the empty plexiglass cage floor|
|electric field strength||5.4 V/m||mean||measured||-||with rats in cage on the outside the plexiglass cage floor|
|electric field strength||8.4 V/m||mean||measured||-||with rats in cage on the inside the plexiglass cage floor; rat exposure value|
|power density||0.187 W/m²||mean||-||-||rat exposure value|
|SAR||0.0093 W/kg||-||calculated||whole body||-|
Apoptosis and lipid peroxidation were significantly increased in the exposure group (group 1) compared to the sham exposure group (group 2). Additionally, in comparison to the cage control (group 3), the superoxide dismutase enzyme activity was significantly increased and the enzyme activity of catalase and the amount of glutathione were significantly decreased in the exposure group. However, in the sham exposure group, apoptosis and all oxidative stress parameters except lipid peroxidation were significantly different compared to the cage control as well.
In histology and ultrastructure, the sham exposure and cage control showed no histopathological changes, while the exposure group exhibited structural changes and capillary congestion in the myocardium, decreased myofilaments and pronounced vacuolization.
There were no significant differences in body or heart weights between the groups.
The authors conclude that exposure of adolescent rats to a 900 MHz electromagnetic field might induce oxidative stress causing morphological alterations in the heart.