Curr Pediatr Res 2012 Volume 16 Issue 1 37 Curr Pediatr Res 2012; 16 (1): 37-41 Effects of electromagnetic waves emitted from mobile phone on auditory evoked potential in school children. Malla Uzwali 1 , Limbu Nirmala 1 , Das A 1 , Paudel BH 1 , Mathur NN 3 and Singh PN 2 1 Department of Physiology, BP Koirala Institute of Health Sciences, Dharan, Nepal 2 Department of Physiology, J.N.Medical College A.M.U. Aligarh, India 3 Department of E.N.T., Maulana AzadMedical College, New Delhi, India Abstract Electromagnetic radiations are emitted from mobile phone. Part of these radiations is absorbed by recipients’ body which is in close proximity to the mobile phone. It has been hypothesized that children absorbs more radiation. This is attributed to their thinner skull and small head size. It might have some debilitating effect in children. Hence, purpose of our study was to assess hearing ability of children, age group ranging from 6- 12 years, before and after 10 min exposure to mobile phone which receives and transmits radiation of 1900 MHz and 850 MHz frequencies respectively. Consented by parents, 30 healthy children having normal hearing level (below 25 dB) were recruited for the study. Auditory brainstem response (ABR) of each child was recorded before and after 10 min exposure to mobile phone. ABR was recorded giving rarefaction, condensation and alternate (rarefaction- condensation) click stimulus for consecutive 3 days, restricting to one stimulus a day. Statistically significant increase in latency of wave III and Interpeak latency (III-V) was recorded with alternate click stimulus, showing some effects on hearing ability of children. However, no measurable changes were observed with rarefaction and condensation click stimulus. Further study is suggested to explore the mechanism of latency change due to alternate click stimulus, and whether it is within physiological range or beyond. Keywords: Auditory Brainstem Response, Electromagnetic radiation, children. Accepted July 22 2011 Introduction Mobile phones are the integral part of modern telecommunications. It has been estimated that more than 4 billion person around world uses mobile phone [1]. It receives and emits electromagnetic radiation. The radiations emitted are absorbed by the body tissue and converted into heat. Thus, widespread use of mobile telephones has given rise to concern about the potential influences of radiation on human health. Many studies were done to see possible effects of electromagnetic radiation in electroencephalogram, auditory brainstem response and various other aspects of the health. As stated, part of radiation emitted by mobile phone handset is absorbed by human head. Hypothetically, these areas would be of a higher risk for tumors in subjects that use mobile phones regularly. The rate at which radiation is absorbed by the human body is measured by the specific absorption rate (SAR). The SAR is expressed in power (watts) by tissue mass (Kg). The SAR is determined by the highest certified power level in laboratory condition. Guidelines were developed by the independent scientific organizations that include safety margins designed to assure the protection of all persons, regardless of age and health. One of the organizations, International commission on Non Ionizing Radiation Protection (ICNIRP) stated SAR limit 2.0 watts/ Kg (W/Kg) averaged over ten gram of tissue. SAR of different mobile phones varies depending on the models. Many studies done to evaluate the effect of electromagnetic radiation emitted from mobile phone on hearing of adult revealed no effects [2, 3]. However, due to smaller head size and thinner skull, children are hypothesized to absorb more energy [4]. This increases the vulnerability of children towards its possible effect on hearing or cognitive function. Material and Methods Subjects and sample size Thirty healthy consented children were allowed to participate in the study. Of the thirty, twenty two were male