Elemental and Molecular and Profiling of Illicit Tobacco

Abstract

Tobacco has been labelled by the World Health Organisation as the largest preventable threat to modern day health, due to the tobacco plant being highly susceptible to bioavailable elements and the accumulation of over 4,000 different chemicals throughout cultivation. The risks of using tobacco are significantly heightened when the tobacco is illicit due to the use of poor grade unregulated tobacco and sub-standard delivery systems. This research that was conducted in collaboration with Lancashire Trading Standards and allows for the profiling of a diverse range of different tobaccos using 88 samples collected from Lancashire Trading Standards, various licit retailers in Preston, France and Sweden.

The aims of this research include; the elemental profiling of tobacco using X-ray Fluorescence Spectroscopy as a rapid handheld qualitative technique, the quantification and comparison of nicotine levels within licit, illicit and niche tobacco using Gas Chromatography – Mass Spectrometry, including a single strand extraction study to determine the possibility of the natural spatial distribution of nicotine along the tobacco leaf and finally, the molecular profiling of tobacco using Fourier Transform Infrared Spectroscopy aided by multivariate data analysis.
Through analysis of spectra collected using X-ray Fluorescence, we were able to determine elemental differences between dried leaf and treated tobacco using fluctuations in elements such as Potassium, Calcium and Iron. The most significant elemental difference between niche and licit tobacco was the presence of Chlorine found within the Snüs.
The extraction and quantification of nicotine using Gas Chromatography – Mass Spectrometry identified significantly higher levels of nicotine present within illicit tobacco when compared to that of a licit cigarette, supporting the theory that illicit tobacco contains higher doses of nicotine leading to higher rates of addiction. Data collected from single stranded extractions identified similar high standard deviations (> 25%) to that as the main nicotine study, supporting the theory that nicotine has inconsistent spatial distribution across the tobacco leaf.
Data that was collected using Fourier Transform Infrared Spectroscopy was pre-processed and vector normalisation was applied. Variable ranking was used to determine the highest discriminative wavenumbers, highlighting spectral fingerprints within the spectra relative to each different type of tobacco, identifying absorptions in the regions of 1050-1150 cm-1, 1350-1480 cm-1 and 1600 cm-1.
This research compares and identifies differences between tobacco available on the licit and illicit market and establishing a platform for the full profiling of licit, illicit and niche tobacco and their constituents, where limited research has previously been conducted.