Factors Influencing the Elution of High-Boiling Components of Cigarette Smoke from Filters

The transfer of high-boiling cigarette smoke components from a filter to the trapping system was studied by adding carbon-14 labelled compounds to filters, smoking cigarettes attached to them, and determining the radioactivity which had escaped from the filter. Transfer or elution was slight when air was puffed through the filter, but appreciable when smoke was puffed through it. Elution is proposed to take place as a result of a compound's vapourizing from a fiber and, instead of recondensing on the fiber, being trapped by an aerosol particle which subsequently escapes from the filter. The effect of the properties of the compound being studied, the aerosol properties, and the filter parameters on elution were investigated. From the study of elution of several compounds on an individual-puff basis, it was found that the relative affinity between the eluted compound and the aerosol or the filter has an important influence on elution. Use of straight-chain hydrocarbons led to the conclusion that there is a linear relationship between percentage of elution and the logarithm of the vapour pressure of the compound being eluted by cigarette smoke. Decrease in aerosol concentration decreases elution; increase in filter and/or aerosol temperature increases elution. Aerosol composition can be important in elution behaviour, as in the apparent relationship between increased moisture content of the aerosol and increased elution of nicotine during the last puffs. Increase in filter length slightly decreases elution, decrease in total denier slightly decreases elution, and change in denier per filament causes no change in elution.