Contemporary exposure to cigarette smoke and noise of automobile manufacturing company workers

• Published in: Journal of public health Vol. 18; no. 3; pp. 245 - 249
• Main Authors: Attarchi, Mir Saeed, Labbafinejad, Yasser, Mohammadi, Saber
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-06-2010; Springer Nature B.V
• Subjects: Automobile industry; Cigarettes; Epidemiology; Factories; Health Promotion and Disease Prevention; Hearing loss; Human exposure; Medicine; Medicine & Public Health; Motor vehicles; Noise levels; Noise pollution; Occupational diseases; Occupational exposure; Occupational health; Original Article; Public Health; Smoking; Statistical methods; Occupational exposure; Noise; Hearing loss; Smoking
• ISSN: 0943-1853; 2198-1833; 1613-2238
• DOI: 10.1007/s10389-009-0298-x

Background
Noise-induced hearing loss (NIHL) is one of the oldest occupational diseases. Evidence has accumulated in recent years on the adverse effects of smoking on hearing among the working population, but the absence of such an association has also been reported. Both cigarette smoking and noise exposure have a common pathway to produce hearing loss.
Materials and Methods
We surveyed the effect of smoking on NIHL in 478 workers in a large automobile manufacturing company who were exposed to unauthorized levels of noise. All required data were obtained using direct interviews and questionnaires. The results of the chi-square test and the regression models are expressed as odds ratios (OR) with 95% confidence intervals (95% CI).
Results
The frequency of hearing loss in smokers was higher than in non-smokers based on model 1 (hearing threshold differences ≥30 dB between 4,000 Hz and 1,000 Hz in both ears; OR 23, 95% CI: 11.90–44.42; p < 0.001) and model 2 (hearing threshold level of >25 dB at 4,000 Hz in the better ear; OR 6.94, 95% CI: 4.53–10.64; p < 0.001). These results were confirmed by the logistic regression statistical method.
Conclusion
It can be concluded that smoking may accelerate noise-induced hearing loss, and smoking cessation may be useful for prevention of NIHL, but more studies are required to confirm this.