Respiratory Symptoms and Paper Dust Exposure among Workers in the Paper Industry in Ethiopia: A Comparative Cross-Sectional Study

Chronic respiratory symptoms are a health concern in the paper industry. This study evaluates the association between personal inhalable paper dust exposure and chronic respiratory symptoms among workers in this industry. In total, 270 workers from the paper industry and 267 from a water bottling factory participated. Chronic respiratory symptoms were assessed using a standardized questionnaire, modified from the American Thoracic Society. A job exposure matrix, based on cross-sectional personal measurements of inhalable paper dust, was used to estimate the exposure-response relationship between cumulative dust exposure and chronic respiratory symptoms. There was a higher prevalence of chronic coughs (27.4% vs. 7.5%), breathlessness (25.6% vs. 11%), coughs with sputum (21.1% vs. 1.1%), and wheezing (25.6% vs. 5%) among paper workers compared to those in the water bottling industry. A Poisson regression analysis revealed that the prevalence ratios for chronic coughs (APR = 3.3 and 95% CI: 2.0-5.4), breathlessness (APR = 2.2 and 95% CI: 1.4-3.4), and wheezing (APR = 4.3 and 95% CI: 2.3-7.7) were significantly higher in paper workers than in water bottling workers. Among paper workers, a significant exposure-response relationship was observed between cumulative dust exposure and chronic coughs after adjusting for age, sex, history of respiratory illnesses, work in other dusty industries, and use of biofuels. As there were only four ever-smokers, smoking was not included in the regression analysis. The results show a significant association between dust exposure and coughing, highlighting the need for control measures to prevent the development of respiratory symptoms among workers.