Prevalence of noise induced hearing loss among Jordanian industrial workers and its associated factors.

BACKGROUND

Exposure to excessive noise is the most common preventable cause of hearing loss. It has been estimated that more than 12% of the global population is at risk for hearing loss from noise and about one-third of all cases can be attributed to noise exposure.

OBJECTIVES

Data on occupational noise and its associated hearing loss are lacking in Jordan. This study aimed to determine the prevalence of noise induced hearing loss (NIHL) among industrial workers in Jordan.

METHODS

This study included all workers who had been exposed to noise at least three years or more in three plants in Madaba Governorate in Jordan. A structured questionnaire was used to collect the data. The occupational noise was measured using a portable calibrated sound meter. Pure-tone air conduction audiometry was performed to determine the hearing thresholds in the frequencies of 250, 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz for both ears of all subjectsRESULTS:This study included 196 workers aged between 20 and 54 years with a mean (SD) of 35.9 (7.2) year. Overall, the prevalence of NIHL among workers was 28.6% (35.0% among those exposed to high level of noise (>85 dB) and 12.5% among workers exposed to low level of noise (≤85 dB)). Age >35 years (OR = 2.7; 95% CI: 1.2-6.1), high noise level (OR = 4.2; 95% CI: 1.6-10.5), exposure of more than 10 years (OR = 2.0; 95% CI: 1.1-5.9), and not using hearing protective devices (OR = 2.7; 95% CI: 1.1-6.6) were significantly associated with increased odds of hearing loss.

CONCLUSIONS

About one quarter of noise-exposed industrial workers in Jordan has NIHL. Age >35 years, high noise level, exposure of more than 10 years, and not using hearing protective devices were significantly associated with increased risk of NIHL.