A case of occupational asthma due to polyurethane was presented. A 56 year old male had been engaged in spraying polyurethane for one year. He developed dyspnea and cough while working six months before. Physical examinations on admission revealed rhonchi and rough breathing sounds. The pulmonary function tests showed an obstructive pattern. After dyspnea disappeared, inhalation provocation tests by polyurethane were made.
When the hardner, the thinner and the paint are mixed together, polyadditive reactions occur between the hardner and the thinner, and a polymer is formed. Although provocation tests by various combinations of materials were made, an asthmatic attack was induced only when the above three materials were mixed together in a spray and inhaled by the patient. Therefore, polyurethane polymer was considered to be the allergen.
