Cigarette filter ventilation allows air to be drawn into the mainstream smoke which, when the ventilation is unblocked, dilutes the smoke. When cigarettes are machine-smoked using the Health Canada Intense method, ventilation holes are blocked and this gives rise to higher smoke yields than those produced under ISO conditions. However, in normal use, few smokers block all ventilation holes; therefore, it is beneficial to study the effect of filter ventilation on human smoke exposure.

To investigate the effect of filter ventilation on exposure, British American Tobacco and R.J. Reynolds Tobacco collated and reviewed data from 11 studies across 9 countries. These studies were performed between 2005 and 2013 and contained data on mouth level exposure (MLE) from 1,690 products with filter ventilation between 0% and 87%. Mouth level exposure of ~6,400 subjects to tar and nicotine was estimated using the part-filter analysis method from spent filter tips.

For each of the countries studied, MLE to tar and nicotine consistently decreased as filter ventilation increased. Across the countries, per cigarette MLE to tar and nicotine decreased 57% and 54%, respectively, as filter ventilation increased from 0% to 87%. Daily MLE to tar and nicotine decreased 61% and 58%, respectively, across the same range of filter ventilation.

Cigarette filter ventilation was associated with a reduction in MLE to tar and nicotine when examined under subjects’ natural smoking behaviour. Therefore, these data do not support the view that smokers fully compensate for cigarette ventilation but instead suggest that smokers of ventilated cigarettes are exposed to lower amounts of nicotine and toxicants.