Abstract
Waterproofing spray, which is often used in homes, can cause pulmonary disorders when a person either inhales the spray directly or is affected by the highly toxic spray components produced by thermochemical decomposition. In this case, a 40+X-year-old man experienced dyspnea after using a waterproof spray in his house while the windows were kept closed. He was therefore admitted to our hospital. On the third hospital day, the dyspnea and cough symptoms worsened, and we diagnosed him to have chemical pneumonitis which had been caused by the inhalation of waterproofing spray. The pathophysiological mechanism of chemical pneumonitis is considered to be as follows ; Fluorine resin, which is used as a water repellent agent antagonizes the pulmonary surfactant, thereby causing alveolar collapse and sometimes inducing chemical pneumonitis. We herein report a case, in which the onset in this patient occurred a few days after the patient’s exposure to the waterproofing spray. He was treated by glucocorticoid and neutrophil elastase inhibitor, and received respiratory care by BiPAP（ bi-level positive airway pressure）. His symptoms improved after these treatments. We think that it is important to carefully observe the clinical course of respiratory symptoms in detail even when the initial symptoms of the patient are not severe.
