Galloni P, Lovisolo GA, Mancini S, Parazzini M, et al. (2005):

The authors conducted a series of experiments to test the response of the cochlear outer hair cell (OHC) activity. OHC motility causes emissions spontaneously and in response to external stimuli. These otoacoustic emisssions (OAE) can be recorded and are used as a simple and non-invasive way to analyze OHC function. The authors focussed on distortion products otoacoustic emission (DPOAE), which are evoked by stimulation with two pure tones of different frequencies.

The authors used Sprague-Dawley rats in their experiments to test the effect of radiofrequency radiation (RFR), at 900 MHz frequency, on DPOAE. A variety of different protocols were used. These included different SAR levels (1 or 2 W/kg), modulation (GSM or CW), exposure time (2 or 3 h/day, 1 or 4 weeks), and EM source (horn or loop antenna).

No changes in the OAE parameters, measured before and after the exposure, were seen.