Health Canada recommends in vitro testing of separately collected gas and particulate phases of cigarette smoke for cytotoxicity and genotoxicity assessment. While these test materials have shown cytotoxicity and genotoxicity in literature, there has been limited data on their chemical characterization, although the gas phase samples are recommended to be tested within an hour of collection. Herein we describe an alternative whole smoke collection procedure which combines gas and particulate phases as “condensates” in ethanol.

Mainstream 3R4F cigarette smoke was generated using Health Canada Intense smoking regimen and collected on a Cambridge filter pad (CFP) connected in series to an ethanol-filled impinger in ice-bath. The CFP was immediately extracted with the impinger content to produce the whole smoke condensates in ethanol. Selected smoke constituents (nicotine, 1,3-butadiene, acrylonitrile, isoprene, benzene, toluene, acetaldehyde, formaldehyde, acrolein and crotonaldehye) in condensates were compared to the whole smoke. The condensates were tested using standard in vitro assays: Neutral red uptake (NRU) for cytotoxicity, Salmonella mutagenicity (Ames), and micronuclei (MN) in TK6 cells for genotoxicity.

Recovery of nicotine in condensates was 99 % in comparison to whole smoke. Remaining constituents were also detected in the condensates, however, their relative proportions varied. The 3R4F condensate was cytotoxic in the NRU assay (1/EC₅₀: 20.83 mL/mg TPM), mutagenic in the Ames assay (TA1537 and TA98), and genotoxic in the MN assay. The proposed collection method captured both gas and particulate phase of a whole smoke and the resulting condensates could be simultaneously used for chemical as well as in vitro biological characterization.