Sweeper’s lung disease: a cross-sectional study of an overlooked illness among sweepers of Pakistan

BACKGROUND Sweepers are prone to develop chronic obstructive pulmonary disease even without tobacco smoking. PURPOSE To investigate roadside dust as a cause of air flow obstruction among sweepers, and the role of spirometry in its preclinical diagnosis. MATERIAL AND METHODS One-hundred nonsmoking sweepers (aged 30-60 years) of both sexes sweeping on roads for 8-12 hours a day for the Capital Development Authority of Islamabad, Pakistan were used as study participants (Group A). One-hundred healthy nonsmokers (aged 30-60 years) in the same socioeconomic group and living in the same environment represented the nonsweeper group (Group B). After proper clinical evaluation and chest X-rays, spirometric evaluation was carried out in both groups. Comparisons were drawn between various spirometric parameters. RESULTS Pulmonary function tests showed that the mean forced vital capacity was 78 ± 1.40 in the sweeper group (Group A) and 83 ± 0.86 in the nonsweeper group (Group B). Mean forced expiratory volume in 1 second was 66 ± 1.67 in Group A and 85 ± 0.85 in Group B (P < 0.05), a difference of 19%. The forced midexpiratory flow was 41% lower in Group A than in Group B (P < 0.0001). The pattern of pulmonary function obstruction was shown to be proportional to the duration of exposure to dust caused by sweeping. CONCLUSION Occupational exposure to dust leads to an obstructive pattern among sweepers. Spirometry is the simplest, noninvasive technique to detect preclinical disease.