The McConnell missile accident. Clinical spectrum of nitrogen dioxide exposure.

Twenty-four men were refueling a missile when a large spill of oxidizer occurred. Three crewmen were exposed to very high concentrations of the oxides of nitrogen. One died within minutes. Severe respiratory distress syndrome developed in the other two, one of whom survived. Twenty-one other workers were exposed to minimal to moderate concentrations of the gas. Most remained asymptomatic while six had shortness of breath, cough, or hemoptysis. The three with persistent symptoms received corticosteroid therapy; the complaints resolved in two. Corticosteroid therapy for four asymptomatic patients who had moderate hypoxemia two weeks after the accident may have aborted the second stage of nitrogen dioxide injury. Six patients with minimal exposure had persisting headaches, visual disturbances, and emotional difficulties. These latter findings may represent an unusual complication of exposure to these gases.