DESCRIPTION AND EVALUATION OF A CIGARETTE-SMOKE GENERATION SYSTEM FOR INHALATION STUDIES

The AMESA Mark III A smoking machine, widely used to generate mainstream cigarette smoke for animal inhalation exposure studies, has been modified to improve operation and reduce maintenance costs. To produce uniform cigarette smoke continuously with a puff frequency ranging from 1 to 3 puffs per minute, the newly designed smoke generator (AMESA Type 1300 Model) was connected to a corresponding number (1 to 3) of peristaltic pumps instead of the piston pump in the AMESA machine. In this way, particle loss from pumping was reduced and the smoke concentration was increased by 10-20%, compared to the AMESA Mark III system. A new ejection system that uses compressed air to blow out the smoked butts was adapted for the generator by AMESA Technologies. This feature reduced the problems previously associated with loading and ejecting of cigarettes and, as a result, reduced cigarette wastage. To further evaluate the AMESA Type 1300 machine, we characterized cigarette smoke generated by using different pumps, puffing volumes, and puffing frequencies. The mass median aerodynamic diameters of smoke particles, measured with a cascade impactor and a diffusion battery, were 0.45 and 0.37-mu-m for 35- and 70-ml puffs, respectively. However, analyses of smoke composition, based on certain gaseous, vapor, and particulate constituents, indicated that there was no statistically significant difference among the different generating profiles.