Non-invasive exposure biomarkers of tobacco smoke exposure in smokers of classic cigarettes and users of e-cigarettes and heated tobacco products

Exposure biomarkers are measurable biological indicators that indicate whether or not the body has been exposed to a particular chemical and the extent of that exposure. Exposure biomarkers are widely used in smokers. Today, there is a growing number of users of various forms of tobacco, especially in the form of e-cigarettes and heated tobaccos. The method of tobacco delivery has an impact on toxicity and biomarker concentrations. Therefore, it is expedient to introduce new biomarkers of tobacco smoke exposure, in addition to existing markers. The ideal biomarker is characterized by non-invasive intake - therefore saliva and urine should be considered as ideal material for determination of biomarkers of exposure. This paper summarizes the existing knowledge of classical and modern biomarkers of tobacco smoke exposure determined from urine and saliva and a brief overview on exposure biomarkers. In addition, the paper provides a description of future developments of exposure biomarkers in different groups of cigarette users.