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Licensed Unlicensed Requires Authentication Published by De Gruyter May 11, 2022

A review of the characteristic properties of selected tobacco chemicals and their associated etiological risks

  • Alfayo K. Maiyo , Joshua K. Kibet ORCID logo EMAIL logo and Fredrick O. Kengara



Despite the quantum of research findings on tobacco epidemic, a review on the formation characteristics of nicotine, aldehydes and phenols, and their associated etiological risks is still limited in literature. Accordingly, knowledge on the chemical properties and free radical formation during tobacco burning is an important subject towards unravelling the relationship between smoking behaviour and disease. This review investigates how scientific efforts have been advanced towards understanding the release of molecular products from the thermal degradation of tobacco, and harm reduction strategies among cigarette smokers in general. The mechanistic characteristics of nicotine and selected aldehydes are critically examined in this review. For the purpose of this work, articles published during the period 2004–2021 and archived in PubMed, Google Scholar, Medley, Cochrane, and Web of Science were used. The articles were selected based on the health impacts of cigarette smoking, tobacco burning kinetics, tobacco cessation and tobacco as a precursor for emerging diseases such as Covid-19.


The toxicity of cigarette smoke is directly correlated with its chemical composition derived from the pyrolysis of tobacco stem and leaves. Most of the harmful toxic substances are generated by pyrolysis during smoking and depends on pyrolysis conditions. Detailed studies have been conducted on the kinetics of nicotine by use of robust theoretical models in order to determine the rate constants of reactions in nicotine and those of nicotine dissociation via C–C and C–N scission, yielding pyridinyl and methyl radicals, respectively. Research has suggested that acetaldehyde enhances the effect of nicotine, which in turn reinforces addiction characteristics whereas acrolein and crotonaldehyde are ciliatoxic, and can inhibit lung clearance. On the other hand, phenol affects liver enzymes, lungs, kidneys, and the cardiovascular system while m-cresol attacks the nervous system.

Summary and Outlook

The characteristics of chemical release during tobacco burning are very important in the tobacco industry and the cigarette smoking community. Understanding individual chemical formation from cigarette smoking will provide the necessary information needed to formulate sound tobacco reform policies from a chemical standpoint. Nonetheless, intense research is needed in this field in order to prescribe possible measures to deter cigarette smoking addiction and ameliorate the grave miseries bedevilling the tobacco smoking community.

Corresponding author: Joshua K. Kibet, Department of Chemistry, Egerton University, Njoro, Kenya, E-mail:


The authors would like to recognize the assistance accorded by the Africa Centre of Excellence in Phytochemicals, Textiles and Renewable Energy (ACE II PTRE) of Moi University, and Egerton University towards the success of this review paper.

  1. Research funding: This study received no specific grants from any funding agency.

  2. Author contributions: AKM: Formal analysis and Writing the original draft. JKK: Conceptualization, Methodology, Formal analysis, Writing & Editing, Validation & Supervision. FOO: Data curation, Formal analysis; Supervision, Writing – review & editing. All authors have read and approved the manuscript.

  3. Competing interests: The authors have no competing interests.

  4. Informed consent: This article has the consent of all the authors.

  5. Ethical approval: Not Applicable.

  6. Availability of data and materials: The data associated with the findings of this study are available from the corresponding author upon reasonable request.


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Received: 2022-01-19
Accepted: 2022-04-21
Published Online: 2022-05-11
Published in Print: 2023-09-26

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