Consistency of arsenic speciation in global tobacco products with implications for health and regulation
Abstract
Background Tobacco smoke is a major risk to the health of its users and arsenic is among the components of smoke present at concentrations of toxicological concern. There are significant variations in human toxicity between inorganic and organic arsenic species and the aim of this study was to determine whether there are predictable relationships among major arsenic species in tobacco that could be useful for risk assessment. Methods 14 samples of tobacco were studied spanning a wide range of concentrations in samples from different geographical regions, including certified reference materials and cigarette products. Inorganic and major organic arsenic species were extracted from powdered tobacco samples by nitric acid using microwave digestion. Concentrations of arsenic species in these extracts were determined using HPLC-ICPMS. Results The concentrations of total inorganic arsenic species range from 144 to 3914 µg kg-1, while organic species dimethylarsinic acid (DMA) ranges from 21 to 176 µg As kg-1, and monomethylarsonic acid (MA) ranges from 30 to 116 µg kg-1. The percentage of species eluted compared to the total arsenic extracted ranges from 11.1 to 36.8% suggesting that some As species (possibly macro-molecules, strongly complexed or in organic forms) do not elute from the column. This low percentage of column-speciated arsenic is indicative that more complex forms of arsenic exist in the tobacco. All the analysed species correlate positively with total arsenic concentration over the whole compositional range and regression analysis indicates a consistent ratio of about 4:1 in favour of inorganic arsenic compared with MA + DMA. Conclusions The dominance of inorganic arsenic species among those components analysed is a marked feature of the diverse range of tobaccos selected for study. Such consistency is important in the context of a WHO expert panel recommendation to regulate tobacco crops and products using total arsenic concentration. If implemented more research would be required to develop models that accurately predict the smoker's exposure to reduced inorganic arsenic species on the basis of leaf or product concentration and product design features.
Citation
Campbell , R C J , Stephens , W & Meharg , A 2014 , ' Consistency of arsenic speciation in global tobacco products with implications for health and regulation ' , Tobacco Induced Diseases , vol. 12 , 24 . https://doi.org/10.1186/s12971-014-0024-5
Publication
Tobacco Induced Diseases
Status
Peer reviewed
ISSN
1617-9625Type
Journal article
Rights
Copyright © 2014 Campbell et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
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