Upper airway and eye involvement in polyurethane shoe sole production workers

This cross-sectional study was aimed to investigate the prevalence of work-related upper and lower airway and eye symptoms in 118 workers in polyurethane shoe soles (PSS) production.

Workplace monitoring of methylene diphenyl diisocyanate (MDI) and solvents was performed. Subjects completed a study-specific questionnaire and underwent anterior rhinoscopy, skin prick tests for common aeroallergens, spirometry, nasal peak inspiratory (NPIF) and expiratory flow (NPEF).

MDI and solvent levels were below threshold limit value-time-weighted average (TLW-TWA) except for two measures of dichloromethane and tetrachloroethylene, respectively, and in one measure of acetonitrile, which were higher then TLW-TWA. In exposed workers the prevalence of cough (p < 0.05) and nasal congestion at rhinoscopy (p = 0.05) was more frequent than in non-exposed workers. Occupational exposure (OR 4.5, 95% CI 1.2-16.5) and a low FEV1 (OR 2.6, 95% CI 1.1-6.3) were significant predictors of cough.

In workers exposed to low levels of MDI and solvents in polyurethane shoe sole production there was a high prevalence of cough and nasal congestion. An improvement in the exhaust ventilation system and other preventive measures were needed.