Electronic nicotine delivery systems (ENDS), or e-cigarettes, are marketed as safer alternatives to tobacco and smoking cessation aids, yet growing evidence links their use to oral disease. We analyzed subgingival plaque and saliva samples from 73 participants using 16S rRNA sequencing, untargeted proteomics, and metabolomics. Male vapers showed disruptions in amino acid and lipid pathways, while females exhibited broader metabolic alterations. Proteomic profiling also demonstrated distinct sex-specific differences. In females, vaping was associated with alterations in platelet activation, cell-cell adhesion, and cellular responses to stress. Male vapers exhibited proteomic changes primarily in protein metabolic process and organelle biogenesis and maintenance. Notably, innate immune-related pathways were differentially modulated between sexes. Proteomic profiling revealed sex-specific immune differences and distinct mechanisms in aldehyde metabolism, including variations in exhaled aldehydes and aldehyde dehydrogenase 3A1 expression. These differences may underlie oral health outcomes: male vapers had higher Community Periodontal Index of Treatment Need (CPITN) scores, potentially linked to sex-based nicotine metabolism. Microbiome analysis further identified sex-specific enrichment of pathogenic taxa, consistent with observed metabolic and proteomic perturbations. Overall, our findings suggest that vaping differentially impacts oral health in males and females through immune, metabolic, and microbial mechanisms.

Date and time: Wednesday, 28 January 2026, 11:30 am – 12:30 pm ET

Presenter: Xiaojia He, Ph.D., Research Scientist at the Center for Toxicology and Human Health, UL Chemical Insights Research Institute

Xiaojia He primarily works on developing systems toxicology approaches to study the influence of occupational and environmental factors such as heavy metal and volatile organic compound exposures on host-microbiome homeostasis and human health. Using immunochemistry and multi-omics approaches, He works to identify potential biomarkers that can help fill knowledge gaps in the exposure-to-disease continuum as well as the exposure-dose-effect continuum and help mitigate adverse effects of those hazardous exposures to protect public health. 

The Inhalation and Respiratory Specialty Section provides a focus for members of the Society of Toxicology dealing with the impact of airborne chemicals and particles on the body. Issues of interest to IRSS include indoor and outdoor air pollution, occupational exposure to airborne contaminants, therapeutic drug delivery by inhalation, deposition and pharmacokinetics of agents delivered by the inhalation route, and interactions between inhaled materials and infectious allergic stimuli.

The title of this webinar is “Balancing Act: Vaping’s Effects on Cardiac Autonomic Function and Oral Microbial Health.”

For more information, see the program agenda here.