The Time Course of Hematological Response to Experimental Exposures of Carbon Monoxide

Abstract

Eight nonsmoking university students were exposed weekly for varied times to varied concentrations of carbon monoxide (CO). Three nonsmoking students were unexposed. Hemoglobin and hematocrit values were obtained from all subjects before, immediately after, 48 hours after, and seven days after each exposure, with weekly and monthly examinations continuing for nearly three months after exposures ceased. Results indicate that hematological response to intermittent CO varies individually, yet hemoglobin and hematocrit means for the eight exposed subjects show an immediate postexposure increase that is significant. This elevation subsides in 48 hours but does not return to pre-exposure levels. In exposed subjects there is also a gradual, less reversible increase in hemoglobin and hematocrit that may continue for two to three weeks after exposures have ceased and for two months maintains levels significantly higher than original values.