Collagen Breakdown and Nitrogen Dioxide Inhalation

Abstract
Measurements of urinary hydroxylysine glycosides indicate that considerable collagen degradation occurred during the reentry intothe earth’s atmosphere of the American astronauts of the Apollo-Soyuz mission. Since the crew accidentally inhaled nitrogen dioxide, arecognized pulmonary irritant, and showed clinical and roentgenographic signs of diffuse chemical pneumonitis, it is likely that collagen degradation occurred in the pulmonary parenchyma.