Assessing the Effect of Simultaneous Exposure to Noise and Cigarette Smoke on Workers' Blood Pressure

Noise, as the most common pollutant in the industrial environment, can lead to hearing loss and negatively affect other organs such as the cardiovascular system. Cigarette smoking is a popular habit among some workers, and can also have a negative effect on the cardiovascular system. This study was aimed to investigate the effect of simultaneous exposure to noise and cigarette smoke on the blood pressure of workers at a manufacturing factory.

This cross-sectional study enrolled 604 workers at a steel factory. Information relating to workers' demography, employment, and risk factors were recorded. Based on the level of smoking per day, workers exposed to noise fell into one of the four following groups: 1) Non-smokers exposed to noise <85 DB; 2) Smokers exposed to noise <85 DB; 3) Non-smokers exposed to noise ≥85 DB; 4) Smokers exposed to noise ≥85 DB. A t-test, analysis of variance (ANOVA), and logistic regression were applied for analysis using SPSS v11.5.

The prevalence of hypertension, cigarette smoking, and exposure to noise ≥85 DB was 11.6%, 15.3%, and 56.4%, respectively, among the workers. The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 112.3 and 73.9 mmHg, respectively. A significant difference was observed between systolic and diastolic blood pressures in four groups (P=0.001). Posthoc test showed a significant difference between groups 1 and 3 (P=0.001). Regression analysis indicated no significant difference in workers who were simultaneously exposed to noise and cigarette smoke.

This study demonstrates that noise is an important factor in terms of hypertension, with no significant differences observed in the prevalence of hypertension between workers who were simultaneously exposed to noise and cigarette smoke. It is suggested that workers' blood pressure should be regularly monitored in noisy environments.