Absorption and Elimination of Carbon Monoxide by Inactive Young Men

Human volunteers were exposed to carbon monoxide at concentrations of < 1, 25, 50, 100, 200, 500, and 1,000 ppm for periods of one-half to 24 hours. Blood samples for carboxyhemoglobin (COHb) were obtained during the exposures and for up to 23 hours into the postexposure periods. Postexposure treatment with oxygen at 1.0 and 3.0 atmospheres was included. Several model equations were tested against the absorption and excretion data; one theoretical equation accurately predicted COHb levels resulting from continuous and discontinuous exposures to unvarying concentrations and from continuous exposure to a steadily rising concentration.