Stefanics G, Kellényi L, Molnár F, Kubinyi G, Thuróczy G, Hernádi I. (2007). Short GSM mobile phone exposure does not alter human auditory brainstem response. BMC Public Health 7:325.
There are about 1.6 billion GSM mobile phones (MPs) in use throughout the world. Due to close proximity of the antenna of the mobile handset to the user’s ear and head, the brain is exposed to electromagnetic fields (EMFs) with a relatively high specific absorption rate (SAR) and it is necessary to study whether EMF exposure from mobile phones can produce any health effects on the human hearing system.
The objective of the study was to learn the possible adverse health effects of GSM mobile phones on the human hearing system.
The study was carried out with 30 healthy volunteers aged 18-26 years. The subjects were randomly assigned to one of two groups: EMF group (true EMF exposure) and control group (sham EMF exposure). The administration of true or sham exposure was double blind. Three types of acoustic stimuli were delivered to the subjects: condensation, rarefaction and alternating 100 ms click sound stimuli. Exposure to 900 MHz pulsed EMF was administered by means of a standard Nokia 6310 mobile phone at maximum peak SAR of 0.41 W/kg for duration of 10 minutes. The auditory brainstem response (ABR) was recorded before and immediately after the exposure. Latencies of wave I, III and V were measured for each stimulus type and subject.
Possible effects of irradiation were analyzed by comparing the latency of ABR waves I, III and V before and after true/sham EMF exposure. This comparison did not reveal any significant differences in the latencies of the ABR waves before and after true or sham EMF exposure in any of the three stimulus conditions.
These results are inconsistent with the results of a pilot study conducted previously in the same laboratory, in which longer exposure duration (15 minutes) was found to cause a significant delay in the latency of ABR wave V. However, because similar studies conducted with various exposure conditions by other investigators support the results of the present study, the authors believe that their previous results should be interpreted with caution and indicate the need for additional control experiments.
Under the experimental conditions applied in the study, a single 10 minute exposure to 900 MHz EMF emitted by a commercial GSM mobile phone did not produce measurable effects on the latency of any auditory brainstem waves. However, additional experiments are needed to test for potential adverse health effects of longer or chronic EMF exposures on the hearing system of humans.