Monitoring nicotine intake from e-cigarettes: measurement of parent drug and metabolites in oral fluid and plasma

Introduction:
This text is a summary of a clinical study investigating the pharmacokinetics of nicotine (NIC) and its metabolites cotinine (COT) and trans-3'-hydroxycotinine (3-HCOT) in both oral fluid and plasma after the use of electronic cigarettes (e-cig) and tobacco cigarettes. The study aims to explore the potential of oral fluid as an alternative biological matrix for non-invasive assessment of nicotine intake.

Key Points:

* The study was a randomized, crossover, and controlled clinical trial involving nine healthy smokers.
* NIC, COT, and 3-HCOT were measured in plasma and oral fluid using liquid chromatography-tandem mass spectrometry.
* NIC and its metabolites were detected in both oral fluid and plasma following both e-cig and tobacco cigarette use.
* Oral fluid concentrations of NIC and its metabolites were higher than those observed in plasma.
* The oral fluid to plasma concentration ratio of both e-cig- and tobacco cigarette-derived NIC peaked at 15 minutes after both administrations and correlated with oral fluid NIC concentration.
* The study suggests that oral fluid may be a suitable alternative to plasma when monitoring nicotine delivery from e-cig for clinical and toxicological studies.

Main Message:
The study found that NIC and its metabolites were present in both oral fluid and plasma following the use of e-cig and tobacco cigarettes. The concentrations in oral fluid were higher than those observed in plasma, making oral fluid a potential alternative to plasma for monitoring nicotine intake. These findings support the use of oral fluid as a non-invasive method for assessing nicotine delivery from e-cig for clinical and toxicological studies, which could have implications for regulatory matters related to e-cig safety and regulation.

Papaseit, Esther, Magí Farré, Silvia Graziano, Roberta Pacifici, Clara Pérez-Mañá, Oscar García-Algar, and Simona Pichini. “Monitoring Nicotine Intake from E-Cigarettes: Measurement of Parent Drug and Metabolites in Oral Fluid and Plasma.” Clinical Chemistry and Laboratory Medicine (CCLM) 55, no. 3 (January 1, 2017). https://doi.org/10.1515/cclm-2016-0405.