To test whether exposure to radiofrequency electromagnetic fields emitted by mobile phone base stations may have effects on salivary alpha-amylase, immunoglobulin A, and cortisol levels in human subjects.
57 participants (35 females) were randomly allocated to one of three different experimental scenarios (22 participants to scenario 1, 26 to scenario 2, and 9 to scenario 3; for further information see exposure details). In every session saliva samples were taken after 10, 25, and 45 minutes for biochemical analyses.
Test persons were divided into three groups and exposed in three different scenarios of five sessions each: Scenario1: low exposure, high exposure, low exposure, medium exposure, low exposure Scenario2: low exposure, medium exposure, low exposure, high exposure, low exposure Scenario3: low exposure, low exposure, low exposure, low exposure, high exposure
|Distance between exposed object and exposure source||6 m|
|Setup||antenna mounted on the outer wall of the building; further GSM-900 and GSM-1800 base stations in the area; different exposure levels gained by the use of shielding curtains; wall painted with shielding paint except for the exposure area|
In scenario 3 from session 4 to session 5 (from "low" to "high" exposure), a significant increase of cortisol was detected, while in scenarios 1 and 2 (sessions 2-4), a higher concentration of alpha-amylase was observed as compared to that in scenario 3. Immunoglobulin A concentration was not significantly related to the exposure.
The authors conclude that radiofrequency electromagnetic fields in considerably lower power flux densities than ICNIRP-guidelines may influence certain psychobiological stress markers.