Self-reported hearing difficulty in workers exposed to industrial dust in southern Brazil

PURPOSE: To investigate the association between self-reported hearing difficulties and occupational exposure to industrial dust in workers in southern Brazil. METHODS: This is a cross-sectional analytical study conducted with data from the National Health Survey (Pesquisa Nacional de Saúde, 2013). The dependent variable was self-reported hearing impairment, and the primary independent variable was occupational exposure to industrial dust. The covariables were: sex, skin color, age in complete years, exposure to noise, and exposure to chemical substances. The variables of occupational exposure to noise and chemical substances were used as adjustment variables (confounding variables), and the analyses were stratified per state (Santa Catarina, Paraná, and Rio Grande do Sul) to verify the difference in magnitude results per region. For the crude and adjusted analysis, the odds ratio (OR) was used as a measure of association, estimated through the logistic regression analysis. The data were analyzed through the software Stata, version 14. RESULTS: Regarding the main exposure, 10.1% of the sample (n = 490) reported being exposed to industrial dust in an occupational environment, while 7.0% reported hearing impairment. In the final analysis, workers exposed to industrial dust were 1.77 times more likely to report hearing impairment when compared to individuals not exposed to this agent. CONCLUSION: There was an association between hearing impairment and exposure to industrial dust in workers in the southern region of Brazil.