Bin Zhou ¹ Jiaxiang Zhang ^2*

• ¹ Third People's Hospital of Hefei, Hefei, China
• ² Anhui Medical University, Hefei, Anhui Province, China

The aim of the study was to investigate the occupational epidemiological characteristics of hearing loss among noise-exposed workers through a cross-sectional study and to explore the impact of combined noise and dust exposure on workers' hearing loss through a longitudinal study.This cross-sectional study revealed that the risk of speech-frequency hearing loss increases with age (OR=1.096, 95%CI=1. 081-1.111). Independent factors influencing high-frequency hearing loss include sex, age, hazardous factors, industry category, and enterprise size. Scientific research and technical services (OR=1.607, 95%CI=1.111-2.324), wholesale and retail (OR=2.144, 95%CI=1.479-3.107), manufacturing (OR=1.907, 95%CI=1.429-2.545), and other industries (OR=1.583, 95%CI=1.002-2.502) are risk factors for high-frequency hearing loss, whereas being female (OR=0.297, 95%CI=0.236-0.373) is a protective factor against high-frequency hearing loss. Independent factors influencing occupational noise-induced hearing loss include sex, working age, hazardous factors, industry category, smoking, and drinking, with the risk of occupational noiseinduced hearing loss increasing with working age (OR=1.045, 95%CI=1.031-1.058). Noise and dust work (OR=1.271, 95%CI=1.011-1.597), other work (OR=0.619, 95%CI=0.479--0.800), manufacturing (OR=2.085, 95%CI=1.336-3.254), other industries (OR=2.063, 95%CI=1.060-4.012), occasional smokers (OR=0.863, 95%CI=0.652-1.142), regular smokers (OR=1.216, 95% CI=0.987-1.497), and excessive drinkers (OR=2.171, 95%CI=1.476-3.193) are risk factors for occupational noise-induced hearing loss, whereas being female (OR=0.496, 95%CI=0.347-0.709)is a protective factor against occupational noise-induced hearing loss. The longitudinal study revealed differences in pure-tone hearing threshold test results at 500 Hz, 1000 Hz, 3000 Hz, 4000 Hz, and 6000 Hz in both ears before and after enrollment among noise-exposed workers (P<0.05).Combined noise and dust exposure (OR=4.660, 95%CI=1.584-13.711), 1st year (OR=1.540, 95%CI=1.128-2.103), 2nd year (OR=1.994, 95%CI=1.409-2.821), and 3rd year (OR=1.628, 95%CI=1.170-2.264) were risk factors for high-frequency hearing loss.Discussion Combined noise and dust exposure is a risk factor for occupational noise-induced hearing loss. Additionally, occupational noise-induced hearing loss is influenced by gender, working age, enterprise industry category, smoking, and drinking. Employers should enhance occupational health management and improve workers' occupational health literacy, with a particular focus on older male workers of long working age, and those with unhealthy habits. Combined exposure to noise and dust may have a synergistic effect on causing high-frequency hearing loss, and comprehensive protective measures should be implemented for workers exposed to both.