Pulmonary effects of inhaled dust and fumes: exposure-response study in rubber workers

Lung function changes and respiratory symptoms were investigated in a cross-sectional study in rubber workers exposed to dust and fumes. To exclude acute pulmonary effects related to "rubber fumes," lung function was measured in curing workers at the start and end of the day shift. Exposure to inhalable dust was measured in all production areas. The results were compared with a reference population from the same geographical region. This study indicates that exposure to "rubber fumes" in curing workers was not related to cross-shift and cross-week decreases in pulmonary function at levels approximately 1 mg/m3 (AM) inhalable dust and 260 micrograms/m3 cyclohexane soluble fraction (CSF). Cross-sectional analyses gave indications for a small loss in pulmonary function in all rubber workers. This decrease in lung function was associated with 10 years of exposure to an average of 2.0 mg/m3 inhalable dust. Our study showed a mean annual decline of 0.08% for the FEV1/FVC ratio and of 10 ml/s for the MMEF. Self-reported chronic respiratory symptoms were not related to dust exposure.