Effects of cigarette rod length on puff volume and carbon monoxide delivery in cigarette smokers.

As part of a continuing series of studies to investigate the variables controlling various topographical aspects of cigarette smoking, the present study examined the extent to which cigarette rod length influenced smoking. Cigarette smoking was examined under conditions in which subjects smoked cigarettes they could not see. Both puff volume and puff duration varied as a direct function of rod length, although they were not highly correlated. Peak flow rate was not affected by rod length. Other results suggest that visual stimulus control and satiation did not affect puff volume. Comparison of puffing whole cigarettes versus short cigarette rods suggests that puff volume, but not puff duration, may be decreased in response to increased pharmacological delivery as a result of particulate build-up during smoking of a whole cigarette. Carbon monoxide (CO) exposure was substantially greater after puffing full length cigarette rods than after short cigarette rods. Comparison of these human CO data with CO delivery from syringe-simulated puffing of full length and short cigarette rods indicates that knowledge of puff volume and duration during human smoking is insufficient for accurately predicting biological (CO) exposure.