Behavior-based yield for electronic cigarette users of different strength eliquids based on natural environment topography.

Introduction: The extent to which electronic cigarette users will compensate for lower nicotine eliquids has implications on the risk associated with regulating eliquid composition. This article elucidates topography as a compensatory mechanism by investigating the impact of nicotine strength on total particulate matter (TPM) and nicotine consumed per puff.
Methods: Thirty-three experienced vape pen users were assigned an NJOY™ VapePen and AVAIL™ brand Tobacco Row eliquid with their usual nicotine strength (L = 6 mg/mL, M = 12 mg/mL, H = 18 mg/mL) and vaped through RIT's wPUMTM vape pen monitor to record every puff during 1 week. Nicotine and TPM yield per puff was determined accounting for the impact of topography characteristics on emissions and used to compute participant-specific mean yield per puff.
Results: Nicotine yields ranged from 0.01 to 0.05 mg/puff and varied widely within each group (L, M, and H nicotine strength). Group-wise mean flow rate was lower for L compared to M (p = 0.2) and duration was higher compared to M (p = 0.09). Larger TPM was consumed per puff for L compared to M (p = 0.07), yet nicotine per puff for L was less than M (p = 0.3). H users took smaller volumes than L (p = 0.1) or M (p = 0.17), and there was little difference between L and M (p = 0.47).Conclusions: Evidence was provided for topography as a compensatory mechanism. Use of low nicotine strength eliquids can increase TPM, which can lead to increase in HPHC. Regulatory review of new products should consider natural use topography and realistic use exposures to nicotine, TPM and HPHCs.