To examine whether exposure to electromagnetic fields has a genotoxic and cytotoxic effect on bone marrow cells in immature (2 weeks old) and mature (10 weeks old) rats.
The following groups of rats were examined (n=8 per group): 1.) immature rats, killed directly after sham exposure period, 2.) immature rats, killed directly after exposure period, 3.) immature rats, killed 15 days after exposure period, 4.) mature rats, killed directly after sham exposure period, 5.) mature rats, killed directly after exposure period and 6.) mature rats, killed 15 days after exposure period.
Four rats were used for the micronucleus test and four rats for the chromosomal analysis and mitotic index.
Modulation type: CW
Exposure duration: continuous for 2 h/day for 45 days
Rats were divided into six groups with eight animals each: i) immature control group ii) immature rats exposed to EMF iii) immature rats granted a recovery period of 15 days after exposure termination iv) mature control group v) mature rats exposed to EMF vi) mature rats granted a recovery period of 15 days after exposure termination
|Exposure duration||continuous for 2 h/day for 45 days|
|Chamber||rats were exposed in a pie cage restrainer for 12 rats made of plexiglas with several air holes; galvanized plate (1mm thick) was placed at the bottom for grounding of the static field|
|Setup||antenna heights were approximately 15 cm; antenna was located in the middle of the pie cage restrainer and fixed as closely as possible to the whole body of the rat (about 6 cm from the head)|
|Sham exposure||A sham exposure was conducted.|
|power||2 W||-||-||-||applied output power|
|SAR||0.76 W/kg||mean||calculated||whole body||0.38-0.78 W/kg (for immature rats)|
|SAR||0.37 W/kg||mean||calculated||whole body||0.31-0.52 W/kg (for mature rats)|
|electric field strength||28.1 V/m||mean||measured||-||± 4.8 V/m (for immature rats)|
|electric field strength||20 V/m||mean||measured||-||± 3.2 V/m (for mature rats)|
The data showed significant increases in chromosome aberrations and micronucleus frequency, while the mitotic index and the ratio of polychromatic erythrocytes was significantly decreased in bone marrow cells of all exposure groups compared with the control group. Additionally, the cytotoxic and genotoxic damage was more remarkable in immature rats than in mature rats. The 15 days of recovery period was insufficient to compensate the genotoxic damage in immature rats after exposure.