Symptoms and lung function in low-exposure to TDI by polyurethane foam manufacturing

A cross-sectional investigation was performed in seven polyurethane foam manufacturing factories. Lung function tests were performed at the factories by spirometric and nitrogen wash-out methods. Sixty-seven persons were investigated before and after the work shift, and exposure to toluene diisocyanate (TDI) was evaluated by subject-carried sampling equipment on the same day. The day mean exposure to TDI was 0.008 mg/m3 (0.001 ppm). In the non-smokers there was an increased frequency of symptoms from the airways reported in the exposed subjects as compared to the unexposed controls. There were, however, no signs of acute or chronic effects on the lung function measured by spirometric and nitrogen wash-out methods, which could not be explained by smoking.