Respiratory symptoms and their association with exposure to respiratory dust among indigo-dyed cotton workers.

Indigo-dyed cotton weavers are exposed to various dust particles that may contain chemical contaminants from indigo fermentation process and can be related to respiratory symptoms. This cross-sectional study thus investigates the prevalence of respiratory symptoms and their association with respiratory dust (RD) exposure among workers in northeastern Thailand. It recruited 146 indigo-dyed cotton weavers. The prevalence of respiratory symptoms was collected by a self-report questionnaire included cough, phlegm, chest tightness, wheezing, and dyspnea. The average RD was 47.9 ± 28.3 μg/m3. Logistic regression models revealed a strong association between RD exposure and respiratory symptoms after adjustment. An exposure to RD ≥50 µg/m3 was associated with 5.05-, 3.58-, 2.88-, and 3.30-fold increased odds ratio of cough, phlegm, chest tightness, and dyspnea, respectively. The study results reveal that RD exposure may contribute to respiratory symptoms among indigo-dyed cotton weavers.