Intake and Uptake of Chemicals Upon Use of Various Tobacco/Nicotine Products: Can Users be Differentiated by Single or Combinations of Biomarkers?

With increasing use of new generation tobacco/nicotine products (TNPs) instead or in addition to conventional cigarettes (CCs), the question arises, whether the user of these new TNPs and CCs can be distinguished on the basis of their exposure in terms of intake and uptake of specific chemicals. For this purpose, the exposure to chemicals for users of 5 product types including CCs, HNB (heat-not-burn products), electronic cigarettes (ECs), oral tobacco products (OT, with the focus on snus), nicotine replacement therapy (NRT) products (only nicotine gum (NG) was considered in this study) was evaluated on the basis of published data. For both intake and biomarker-based uptake, 4 relative exposure levels with the assigned values from 1 (lowest exposure) to 4 (highest exposure) were defined resulting in exposure level patterns. Unique single-biomarker-based exposure levels were found for smokers (11 chemicals), vapers (1 chemical) and non-users (NU, 1 chemical). A few selected biomarkers (usually with relative levels of 3–4) were found to be sufficient for unequivocal differentiation of one user/NU group from the other 5 groups. The impact of dual-product use is also briefly discussed. [Contrib. Tob. Nicotine Res. 30 (2021) 167–198]