This study aimed at determining whether exposures to organic dusts were associated with decreases in lungs function among workers exposed to cotton dust in a hosiery unit manufacturing pure cotton garments. In a cross-sectional study, 287 employees underwent lungs function testing in accordance with the National Institute of Occupational Safety and Health (NIOSH) spirometric guidelines. Workers were selected with the help of stratified random sampling of age 19–50 years (participation rate 82.0%). A modified NIOSH questionnaire was used to elicit information from them. We also measured personal dust and fine particulates (aerodynamic diameter of 2.5 micron and less, PM2.5) in the working areas near the workers, and these pollutants were measured using a personal dust sampler and a DustTrakTM, respectively. Concentrations of total dust and PM2.5 varied among the different areas of a hosiery plant. The deleterious effects of cotton dust were higher in smokers than non-smoker workers. An association between exposures to cotton dust and to PM2.5 and lungs function in the study population were found. This study shows association with lungs function arising from exposure to organic dust and PM