Nine patients, as employees of a drug firm exposed to pancreatin and other organic substances in dust form for long periods of time, complained of non-specific breathing disorders and exercise dyspnoea. Investigation revealed predominantly restrictive-obstructive disorders of ventilation with diffuse emphysema and evidence of abnormal oxygen diffusion. In two patients the chest X-ray revealed signs of acute alveolitis, in a third a marked pulmonary fibrosis after exposure for several years. Six of seven patients reacted positively to a prick test with pancreatin. Precipitating antibodies were demonstrated in only one patient. Immunopathological and chemical-toxic effects of pancreatin dust may be causes of the described pulmonary disease.