The aim of the current study was to assess the pulmonary toxicity of tannins in guinea pigs. An artificial dust was prepared by coating cellulose with tannins removed from DB 01-88 cotton dust. The artificial dust contained 21 mg tannin per g dust. No respiratory response was obtained in guinea pigs exposed to the tannin-coated cellulose dust. Exposure to DB 01-88 cotton dust which had been extracted with solvents to reduce tannin content, produced a pulmonary response similar to that obtained following exposure to untreated DB 01-88 dust. Results provided no evidence for tannin contribution to the respiratory reaction in the animal model.