Kayabasoglu G, Sezen OS, Eraslan G, Aydin E, Coskuner T, Unver S. Effect of chronic exposure to cellular telephone electromagnetic fields on hearing in rats. J Laryngol Otol. Nov 9, 2010. Ahead of print.
Electromagnetic waves emitted by a cellular telephone impact the head and, specifically, the ear region. Detrimental biological effects of these electromagnetic waves have not been proven, but they are possible.
The objective was to study the effects of electromagnetic fields emitted by cellular phones on the hearing of rats.
Forty rats (20 adults and 20 newborns) were divided into 4 groups: two groups (10 adults and 10 newborn rats) were exposed to electromagnetic waves (SAR=0.934 W/kg) 6 hours per day for 30 days, and two groups were “kept in an environment without electromagnetic waves for 30 days”. Distortion product otoacoustic emissions (OAE) were measured in each group before and after the 30-day period.
The mean distortion product OAE values in the exposed and in the control rats were not significantly different either in the adult or in the newborn rats. The values of distortion product OAE measured on day 0 and on day 30 in each group were not significantly different.
Interpretation and Conclusion
These results are consistent with findings from other studies that did not find any effects of cellular telephone electromagnetic waves on distortion product OAE or on other hearing parameters. These include experimental studies in human volunteers with short-term (10-min) exposure, epidemiological studies and experimental animal studies with long-term exposure. The study shows that “exposure to cellular telephone electromagnetic waves for 6 hours a day for a period of 30 days had no significant effect on hearing (at least at the outer-ear, middle-ear and cochlear levels) in adult and newborn rats”. The authors point out that humans using cellular phones are exposed for longer periods, and the newer phones emit higher level radiofrequency radiation. They conclude that “until a study is undertaken which simulates real-life conditions more accurately, users should be cautious about the harmful effects of the electromagnetic fields emitted by cellular telephones”.