Effects of Exposure to Low-Level Carbon Monoxide at High Altitude in SensitiveSubjects

摘要

The study involved acute exposures of 18 male non-smokers to air with 100 ppmcarbon monoxide (CO) or clean air under sea level and simulated high altitude (2.1 km). The subjects had physician-diagnosed ischemic heart disease and stable angina and were not acclimated to high altitude. The subjects took a cardiopulmonary monitored graded exercise test to determine whether CO exposure at simulated high altitude can cause greater changes in respiratory physiological, cardiological, or hemodynamic parameters than the same CO exposures at sea level. The authors estimate that individuals with coronary artery disease exposed to the altitude of Lake Tahoe (6229 ft.) would experience a 35% decrease in the time of onset for CO-related angina if ambient CO exposures were increased from the current level of the California State Air Quality High Altitude Standard of 6 ppm or 8 hours to an ambient concentration of 9 ppm for 8 hours, the current National Ambient Air Quality Standard and the current California State Sea Level Air Quality Standard.