Noise-induced hearing loss among workers in textile factory

Abstract

Abstract Introduction: Noise-induced hearing loss (NIHL) is one of the most common chronic health problems, which produces gradual progressive impairment and disturbs the patient’s quality of life. Industries in general and especially textile ones produce noise levels that, if intensified, can cause damage to worker’s hearing. Hence, premature hearing loss is a well-known outcome of noise exposure at work in industrial workers. Aims of the work: The aim of the study was to assess hearing threshold levels among exposed patients and to compare them with the nonexposed control group and to evaluate other variables such as outer hair cell and medial olivocochlear bundle function represented with transient evoked otoacoustic emissions (TEOAEs) testing with and without suppression and to find the relationship with duration of exposure if any. Patients and methods: The study included 145 patients and same number of controls who were exposed to hazardous levels of noise for variable durations. All participants were subjected to audiological examination including basic audiological evaluation, otoacoustic emissions, and otoacoustic emissions with contralateral suppression (CAS). Results: Of the 145 patients (290 ears), 214 ears showed sensorineural hearing loss (73.8%). Sensorineural hearing loss was mild in 63 (43.44%) ears, moderate in 82 (56.55%) ears, and severe in 69 (47.58%) ears. TEOAEs were found in those with mild hearing loss with significantly lower amplitudes. Intact suppression (CAS) was significantly lower for the study group than for the control group. However, there was no significant difference in level of suppression for different duration of exposure. Conclusion: A high incidence for NIHL is present among workers in textile factories, which indicate the mandatory use of different protective measures. CAS can be used as a predictor for the susceptibility to NIHL.