Development and assessment of a novel standardized method for preparation of whole cigarette smoke condensate (WCSC) for toxicity testing of cigarette smoke

Cigarette smoke condensates provide toxic effects data for cigarette products, but the lack of a standardized preparation method yields inconsistent results. This study developed a standardized whole cigarette smoke condensate (WCSC) preparation method, encompassing both particulate and gaseous phases. The goal of this study was to obtain a WCSC of consistent quality by maximizing cigarette smoke concentration. The effectiveness of the method was verified by evaluating the concentrations of total particulate matter (TPM) and organic compounds (OCs: nicotine, triacetin, glycerin, acetaldehyde, and acetone) in the samples at each step of preparing the WCSC from cigarette smoke: (1) generating cigarette smoke using the HCI method, (2) collecting particulate and gaseous phases in cigarette smoke using the Cambridge filter (using modified ISO method) and Dulbecco's phosphate buffered saline (DPBS; the maximum allowable TPM mass per the one Cambridge filter is 537 mg), (3) extracting TPM collected on the Cambridge filter using methanol (the maximum TPM mass that can be effectively extracted using 5 mL of methanol is 1085 mg), (4) removing methanol from the TPM extract using the N₂ evaporation method (the relative recovery of OCs by N₂ evaporation is 97.3 ± 0.96 %), and (5) mixing the TPM residue and DPBS-absorbing gaseous phase of cigarette smoke (relative recovery of OCs in the WCSC compared to the TPM residue and the DPBS is 94.7 ± 0.52 % with fairly good reproducibility and RSD values below 5 %).