|
|
In this study the authors conducted experiments on eight healthy young men, average age 24.8 years. The men were exposed to 900 MHz fields, pulsed with 217 Hz, pulse width 217 µs. An antenna was positioned 10 cm behind the subject's head. The power-flux density was approximately 1 W/m², and the maximum local SAR in the head (averaged over 10g tissue) was 0.025 W/kg. The study was designed to assess the effects of the RF fields on salivary levels of melatonin, cortisol, neopterin, and IgA. Melatonin and cortisol are hormones that have a different pattern of secretion by day and night, and whose secretion is controlled by the pineal and pituitary glands respectively. Since these glands are located at the base of the brain, it has been suggested that they might be susceptible to the effects of RF fields near the head. Neopterin and IgA are substances that are part of the immune system. Before the subjects were exposed to the RF fields, they underwent five sessions, each of 4 hours duration, to check that the conditions of the experiment did not cause changes in levels of the test substances, compared with base-line levels. The subjects then completed twenty 4-hour sessions. In half the subjects were RF-exposed and in the others sham-exposed. Half of the experiments were conducted in the daytime and half at night. The results showed that there was no difference between RF exposure and sham exposure in rate of salivary flow or in salivary concentrations of the four substances tested.
|
|