1.) To study the effects of a 900 MHz electromagnetic field on organs of immune system (spleen, thymus, bone marrow), polymorphonuclear leukocytes and plasma of immature and mature rats, focusing on changes in the enzymatic and non-enzymatic antioxidant system, plasma antioxidant capacity, lipid peroxidation, and oxidant parameters such as NO level and myeloperoxidase enzyme activity;
2.) To determine whether there is any difference between immature and mature rats in terms of oxidative damage caused by electromagnetic field exposure; and
3.) to test whether electromagnetic field-induced damage is reversible in immature and mature rats.
24 immature (2 weeks old) and 24 mature rats (10 weeks old) were divided into six groups of eight rats: two control groups, two exposure groups, and two recovery groups (kept for 15 days after exposure).
Exposure duration: continuous for 2h/day on 45 days
Rats were divided into six groups: i) immature control rats ii) immature rats exposed to EMF iii) immature rats exposed to EMF + kept for 15 days after exposure iv) mature control rats v) mature rats exposed to EMF vi) mature rats exposed to EMF + kept for 15 days after exposure
|Exposure duration||continuous for 2h/day on 45 days|
|Setup||rats placed in a restrainer with a galvanized plate under it for grounding; 15 cm high antenna positioned in the center of the restrainer about 6 cm from the rat's head; due to the rat's movement the distance between antenna and rat's head varied from 6 to 9 cm|
|electric field strength||19.76 V/m||minimum||measured||-||average for immature rats|
|electric field strength||28.58 V/m||maximum||measured||-||average for immature rats|
|electric field strength||18.15 V/m||minimum||measured||-||average for mature rats|
|electric field strength||23.61 V/m||maximum||measured||-||average for mature rats|
|SAR||0.38 W/kg||minimum||calculated||whole body||for immature rats|
|SAR||0.78 W/kg||maximum||calculated||whole body||for immature rats|
|SAR||0.28 W/kg||minimum||calculated||whole body||for mature rats|
|SAR||0.48 W/kg||maximum||calculated||whole body||for mature rats|
The data showed substantial, deleterious biochemical changes in oxidative stress metabolism after electromagnetic field exposure. Antioxidant enzyme activities (catalase and glutathione peroxidase), glutathione levels in lymphoid organs and the antioxidant capacity of the plasma decreased in mature and immature rats, but lipid peroxidation and nitric oxide levels in polymorphonuclear leukocytes and plasma as well as myeloperoxidase enzyme activity increased. Oxidative damage was tissue specific and recovery after 15 days was limited, especially in immature rats.
The data showed higher levels of irreversible oxidative damage in the lymphoid organs of immature rats than in mature rats.