Respiratory symptoms and diseases among workers in the soft tissue producing industry.

AIMS To correlate the prevalence of respiratory tract symptoms and diseases with dust and fibre exposure in the soft tissue industry in Germany. METHODS Ambient monitoring was performed for inhalable, respirable dust and fibres in seven soft tissue producing factories. In 441 workers (72 controls, 90 moderate, 279 high exposure) a standardised questionnaire on respiratory symptoms, diseases, occupational history, and smoking habits was used. Crude differences in the prevalence of respiratory symptoms and diseases were assessed. Logistic regression analysis was used to determine the relation between the respiratory symptoms/diseases and the cumulative dust and fibre exposure, respectively, while adjusting for age, gender, smoking habits, and factory. The effects of exposure intensity and duration were differentiated by categorising dust/fibre concentrations and years of exposure separately and setting up logistic regression models. RESULTS The mean concentrations for inhalable, respirable, and fibrous dusts were 10.3 mg/m(3), 0.22 mg/m(3), and 415,000 fibres/m(3). Adjusted odds ratios (OR) with relation to cumulative dust exposure intensity were significantly raised for blocked nose (18.2), mucosal irritation (6.5), dry nose (8.9), cough (3.5), phlegm (7.5), exercise induced dyspnoea (2.6), hoarseness (11.3), and sneezing attacks (7.9) (ORs for highest exposure categories). Cumulative dust or fibre exposure had no significant effects on the prevalence of respiratory diseases. For all symptoms with significantly raised ORs, combined effects of intensity and duration of exposure were found. CONCLUSIONS Because of the high prevalence of respiratory symptoms a reduction of dust exposures is recommended. Chronic exposure effects could not be found in this study, however, a healthy worker effect has to be considered.