The objective of this study was to investigate the contribution of various smoke constituents to the toxicological activity of total particulate matter(TPM) or the gas/vapor phase(GVP). These components included phenol compounds, aromatic amines, polycyclic aromatic hydrocarbons, heterocyclic amines, and carbonyl compounds. The mutagenic and cytotoxic potencies were assessed using the Salmonella mutagenicity assay with S. typimurium TA98 strain and the neutral red uptake cytotoxicity assay(NRU) with BALB/c 3T3 fibroblast cells, respectively. The Salmonella mutagenicity test showed that heterocyclic amines exhibited significantly higher levels of toxicity compared to other smoke constituents. Among them, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline(MeIQ) was shown the most mutagenic compound with a specific mutagenicity of $7.9{ imes}10^5;revertants/{mu}g$. An analysis of the possible contribution revealed that MeIQ account for only 0.85% of the 2R4F-TPM mutagenicity in TA98. NRU data demonstrated that high cytotoxic activity was obtained for hydroquinone, formaldehyde, and acrolein. Based on the results of the present study, the contribution of acrolein to the cytotoxicity of the GVP fraction was calculated as 61%. Thus, a large proportion of the cytotoxic activity of this complex mixture, cigarette smoke gas phase, can be attributed to the acrolein.