Hairs causing pulmonary emboli. A rare complication in long-term intravenous studies in dogs

Hair particles as arterial lung emboli were an unexpected side effect in a long-term intravenous toxicity study in Beagle dogs. These emboli led to arterial thrombosis and perivascular granulomas or focal interstitial pneumonitis. The emoblic lesions were not severe enough to cause infarction of the lung. This high incidence of hair embolism was related to a moderate solvent-specific chronic dermatitis at injection sites.