Two groups consisting of 21 teenagers (15.9 +/- 2.3 years) and 21 adults (30.9 +/- 5.6 years) were exposed. Additionally, 42 subjects were regrouped to 23 male and 19 female subjects in order to see any discrepancy in the physiological parameters between the sexes.
|continuous for 30 min
|Subjects rested on the experimental bed in a supine position.
|A headphone was modified to install a folder-type cellular phone on the left side of the head. The lower part of the cellular phone with buttons was wrapped up with 5 mm thick insulating material in order to prevent the subjects from feeling the generated heat.
|A sham exposure was conducted.
|Real and sham exposures were performed in a double blind test. However, the exposure sequence was not randomized, sham exposures were performed first in order to avoid interference with previous real exposures. Between sham and real exposures, the subject took a 30 min break.
In the teenager group, the physiological parameters did not reveal any significant changes regardless of real or sham exposure and exposure duration, but the skin resistance decreased significantly under real exposures. This decrease indicates that radiofrequency electromagnetic fields might stimulate teenager's autonomic nervous system, resulting in sweat secretion. Ten minutes after the exposure termination, the skin resistance returned to the initial resting value.
In contrast, there were no significant changes in the physiological parameters in the adult group, regardless of the real or sham exposure and exposure duration.
For the regrouped 23 male and 19 female subjects, all the parameters were unaffected during the exposure except for decreased skin resistance of the male subjects.