The objective of this study was to evaluate a modified air-liquid interface BALB/c 3T3 cytotoxicity method for the assessment of smoke aerosols in vitro.

The functionality and applicability of this modified protocol was assessed by comparing the cytotoxicity profiles from eight different cigarettes. Three reference cigarettes, 1R5F, 3R4F and CORESTA Monitor 7 were used to put the study into perspective and five bespoke experimental products were manufactured, ensuring a balanced study design. Manufactured cigarettes were matched for key product characteristics such as nicotine delivery, puff number, pressure drop, ventilation, carbon monoxide and blend, but significantly modified for vapour phase delivery, via the addition of two different types and quantities of absorptive carbon.

The results demonstrate cytotoxicity for all products tested, with clear and statistical differences between the balanced experimental products when compared to the control. In fact the assay was able to distinguish between all vapour phase altered and reference products, in a statistical manner.

This study has further characterised the in vitro vapour phase biological response relationship and confirmed that the biological response is directly proportional to the amount of vapour phase toxicants available in cigarette smoke, when using a Vitrocell^® VC 10 exposure system. This study further supports and strengthens the use of aerosol based exposure options for the appropriate analysis of cigarette smoke induced responses in vitro. This may be especially beneficial when comparing aerosols generated from alternative tobacco aerosol products, particularly those with reduced vapour phase toxicants, which are not assessed using standard in vitro techniques.