Carbon monoxide: Dosimetry in occupational exposures in Denver, Colorado.

The occupational carbon monoxide (CO) exposure of Denver traffic control personnel was evaluated during 8-hr workshifts using three parameters: (1) 98, 8-hr time-weighted average breathing zone air samples (personal dosimetry); (2) before- and after-workshift CO breath samples; and (3) 8-hr moving average, ambient CO levels during the fall and winter months. Different shifts and work experiences were taken into consideration. The data revealed greater CO exposure in subjects working on the street than controls working inside downtown buildings with respect to breath CO concentration and breathing zone air samples. The CO concentrations in the after-workshift breath samples were closely associated with the 8-hr time-weighted average CO levels. The greatest source of CO to the sample population was cigarette smoking, followed by occupational-related sources, and finally, the ambient background CO levels.