Road Traffic Noise and its Effect on Brain Stem Auditory Evoked Potentials in Traffic Policemen

Background and objectives: A major contribution to the noise isvehicular noise. The traffic policemen engaged in controlling traffic noise, particularly at heavy traffic junctions, belong to the high risk group to be affected by health hazards of noise pollution. Among all objective methods of hearing evaluation, brainstem auditory evoked potential (BAEP) is considered the most used precocious potential on clinical practice. Objective was to measure BAEP in traffic policemen and compare it with normal controls. Methods and materials: Study population included 30 traffic policemen manning road traffic and 30 age matched controls who were involved in administrative work. Sound pressure level of road traffic noise was measured using sound level meter. BAEP was recorded in traffic policemen and was compared to normal controls. Results: Mean values of sound pressure level measured at various traffic junctions was 83.12+4.23 dB(A) compared to 65.10+0.47 dB(A) (p<0.001) measured in and around medical college campus. Significant prolongation (p<0.05) of all wave latencies (I, II, III, IV and V) of BAEPs with non significant prolongation of IPL I-III, III-V and I-V in traffic policemen as compared to controls. Interpretation and conclusion: Long term exposure to vehicular noise of high sound pressure level resulted in prolongation of wave latencies of BAEP in traffic policemen compared to controls. Thus it is suggested that some preventive modalities for hearing conservation in the form of safety equipment, periodic check-ups (using audiometer, BAEP) and duty scheduling for exposure limitation can be suggested and awareness should be created among traffic policemen about the harmful effects of noise on hearing by implementing education and training programmes.