The effect of smoke age and dilution on the cytotoxicity of sidestream (passive) smoke.

Decreases in the mortality of monolayer cultures of L-929 cells exposed to sidestream (passive) smoke with increases in smoke age and dilution have been reported. In the current study, the concentration of sidestream smoke (SS) to which cells were exposed was directly correlated with % mortality (r = 0.987) having 0% mortality at a concentration of 1.19% and a calculated mortality of 9562% at a concentration of 100%. The In of % mortality was correlated with increases in smoke age (r = -0.9999) and the regression equation was used to calculate 0 mortality at an age of 30 s and 393% mortality at the time of smoke generation. In addition, when sidestream smoke generated from a low-yield, filtered, modern design experimental cigarette was compared with that generated from a high-tar non-filtered reference cigarette, a lower number of puffs of smoke from the low-yield cigarette than from the high tar cigarette was necessary to yield 50% mortality of cells.