BackgroundThe most common risks for street sweepers are respiratory symptom and airway obstruction increases as a result of dust inhalation. The aim of this study was to compare the respiratory symptoms and pulmonary functions of dust-exposed street sweepers with those of unexposed individuals.MethodsThis was a retrospective cohort study of 84 street sweepers with occupational dust exposure (exposed group) and 80 office workers (control group) working for the municipality of Zahedan in Iran. Each of the participants completed the American Thoracic Society respiratory questionnaire, and their lung functions were measured using a calibrated spirometer.ResultsThe respiratory symptom frequencies were significantly higher in the exposed group than in the reference group (P < 0.05). Specifically, coughing was the most common complaint of the street sweepers (81%) when compared to the controls (16.3%). The means of the peak expiratory flow and forced expiratory flow at 25%–75% of the pulmonary volume were significantly less in the exposed group than in the control group.ConclusionOccupational exposure and unhealthy working conditions are the most likely causes of mild obstructive disease and pulmonary function parameter changes. Providing street sweepers with the appropriate respiratory protection equipment, as well as periodic spirometry for the early diagnosis of pulmonary dysfunction, could be effective for preventing many types of pulmonary damage.