Carbon monoxide exposure in individuals working along Rådhusgata, Oslo, Norway, 1987.

Using portable CO-monitors, exposure for CO was measured in 126 people, both smokers and non-smokers working along Rådhusgata, Oslo, Norway. These values were compared to values of CO measured in blood (HbCO) or end-expired breath (CO-EEB) both in the morning when they came to work and in the afternoon. In non-smokers, both HbCO and CO-EEB increased slightly during the day. The morning values were higher than those measured in a less polluted area, Drammen, and were highest in those individuals driving to work as opposed to taking the train or bus. No individuals had values of HbCO greater than 1.5%, the upper suggested limit in Norway. Values of CO in outdoor air were at or above the recommended 8-hour limit of 9 ppm.