The prevalence of chronic and acute respiratory symptoms and ventilatory capacity were studied in a group of 71 workers employed in animal food processing. A control group of 55 unexposed workers was also included in the study. A significantly higher prevalence for most of the chronic respiratory symptoms was found among the exposed than among control workers. Exposed smokers had a significantly higher prevalence of chronic cough, chronic phlegm, chronic bronchitis and chest tightness than control smokers. The values for FVC, FEV1 and FEF50 measured in the exposed workers were significantly lower in comparison to predicted normal lung function values. In smokers all the measured parameters of ventilatory capacity were significantly lesser than predicted. For non-smokers only FVC and FEV1 were below normal. Our data indicate that occupational exposure to animal food may cause the development of acute and chronic respiratory symptoms and impairment of ventilatory capacity.