Vape flavoring chemicals and oral fibroblast viability

The widespread use of electronic cigarettes is due to the variety of appealing flavor additives marketed to consumers. Although perceived as a less harmful alternative to traditional smoking, emerging evidence suggests that inhaled e-cigarettes aerosol poses multiple risks on oral health. Oral fibroblasts which maintain the extracellular matrix and support wound repair, may be vulnerable to chemical injury. While the toxic effects of base e-liquid components such as nicotine have been investigated, limited research has addressed how added flavoring chemicals influence oral fibroblast survival and stress responses. A comprehensive search was conducted across PubMed, ScienceDirect, and Google Scholar to identify peer-reviewed studies evaluating the biological impact of flavored e-cigarette exposure on human oral fibroblasts. Collective findings revealed consistent mechanistic trends: flavoring chemicals, especially aromatic aldehydes such as cinnamaldehyde and vanillin, induced adverse cellular responses, increasing intracellular reactive oxygen species, and triggering oxidative modifications. These oxidative injuries such as protein carbonylation promote pro-inflammatory responses in oral fibroblasts, specifically heightened secretion of cytokine interleukin-8 and lipid mediator prostaglandin E₂, which contribute to tissue breakdown. Increased apoptosis, impaired cell survival, and senescence were reported following longer exposure durations. In contrast, menthol and fruit flavors produced moderate responses, while unflavored aerosols showed little toxicity. These results emphasize that flavored e-cigarette products may accelerate oral tissue deterioration, undermining fibroblast health, and limiting the capacity for tissue repair. As flavored aerosol use remains prevalent among the youth, understanding its toxicity is crucial to advancing public health policies and the regulation of vaping products.