Abstract
The diffusion of CO and CO2 through the wrapper of cigarettes was studied by direct measurement under steady-state conditions, simulating the conditions which obtain during puffing. Cigarettes made with porous paper, with perforated paper and with ventilated filters were studied. The diffusion of CO and CO2 from cigarettes was found to be strongly influenced by the mode of cigarette ventilation. The greatest effect of diffusion on CO delivery was found for cigarettes where ventilation was achieved by ventilating the filter. The influence on diffusion of the type and amount of burn chemical applied to the paper is described as well as changing the average pressure drop across the cigarette. It was found that normal levels of burn chemicals added to the paper will only slightly decrease the fraction of CO diffusing through the wrapper.