BACKGROUND: Smokeless tobacco (SLT) products, comprising carcinogens, flavours, additives, pose significant health risks, including addiction, oral diseases, and cancers. Nicotine absorption in SLT products is strongly influenced by pH, as alkaline environment enhances nicotine's bioavailability and addiction potential. Despite their prevalence in low- and middle-income countries like India, the relationship between pH, nicotine absorption, health impacts remains underexplored. This study aims to generate evidence on pH's role in SLT product nicotine absorption, addiction, and toxicity to inform regulatory policies under WHO FCTC Articles 9 and 10.
METHODS: A bibliometric analysis was conducted using data from Scopus, Web of Science, PubMed to identify trends, influential contributors, and thematic areas related to pH-nicotine relationship in SLT products. Search terms included combinations of "smokeless tobacco," "pH," "nicotine absorption," and related keywords. Biblioshiny (R package) was used to evaluate co-authorship networks, keyword co-occurrence, thematic maps, and research trends.
RESULTS: A total of 42 studies were identified after removing duplicates, 29 articles were analysed. The analysis identified 29 relevant articles spanning 17 years, with an average annual growth rate of 5.2% in publications. A co-occurrence network revealed 34 unique keywords, with “pH dependency” and “nicotine absorption” being the most frequently associated terms. The USA contributed the highest number of studies (40%), followed by India (25%) and Sweden (15%). Lotka’s law showed that 10% of the authors accounted for 50% of the publications. Thematic mapping identified four major clusters: nicotine bioavailability, pH modulation, health impacts, and regulatory implications. Temporal trends showed a 60% increase in publications on nicotine pharmacokinetics over the past five years.
CONCLUSIONS: This bibliometric analysis underscores highlights pH's role in nicotine bioavailability in SLT products, driving addiction and health risks. Findings support setting pH and nicotine thresholds to reduce harm and aid WHO FCTC Articles 9 and 10 implementation, with further research needed to strengthen regulations.