ABSORPTION BY NON-SMOKERS OF CARBON MONOXIDE FROM ROOM AIR POLLUTED BY TOBACCO SMOKE

The mean increase of 1% COHb among the non-smokers was similar to the mean increase for the smokers of 0·7% for each cigarette smoked, suggesting that the amount of CO which the non -smokers absorbed by passive smoking was about the same as would be expected if they had actively smoked and inhaled one cigarette.

Abstract

Twenty volunteers spent a mean of 78 minutes seated in an unventilated smoke-filled room of approximately 43 c.m. The smoke was produced by burning or smoking eighty cigarettes and two cigars. The average ambient carbon monoxide (CO) concentration was 38 p.p.m. Blood-samples taken before and after the exposure showed an increase in carboxyhæmoglobin (COHb) in all volunteers. The mean COHb of the twelve non-smokers increased from 1·6% to 2·6%, while the six cigarette smokers, all inhalers, besides having significantly higher initial levels, also showed a greater increase from a mean of 5·9% to 9·6%. The two cigar smokers, one an inhaler the other a non-inhaler, showed respective COHb changes similar to the cigarette smokers and non-smokers. The mean increase of 1% COHb among the non-smokers was similar to the mean increase for the smokers of 0·7% for each cigarette smoked, suggesting that the amount of CO which the non-smokers absorbed by passive smoking was about the same as would be expected if they had actively smoked and inhaled one cigarette.