LGC develops new methodology to measure arsenic in tobacco products
05 Jul 2011
New method determining distribution of arsenic provides fresh insight into the composition of tobacco and cigarette smoke
Scientists at LGC, the UK’s National Measurement Institute for chemical and bioanalytical measurement, have developed a new, sensitive method to determine the low levels of arsenic species present in cut tobacco and mainstream cigarette smoke.
Arsenic, together with five other metals (Cd, Cr, Ni, Hg, Se), is routinely measured in tobacco blends and cigarette smoke. However, to date, there is little available information concerning the specific chemical forms of arsenic in these matrices.
Group Research & Development Centre (GR&D Centre) of British American Tobacco (BAT), in support of their work programme into tobacco harm reduction, approached LGC to develop appropriate analytical methods capable of identifying the chemical forms (species) of arsenic in cured tobacco and mainstream cigarette smoke.
Arsenic in soil is believed to be absorbed naturally by tobacco plants, and is therefore a low level constituent in tobacco products. It partly transfers into smoke when a cigarette burns. Arsenic’s toxicity is dependent on both the amount and also its exact chemical form. New, sensitive and selective methods to identify the presence of the various arsenic species in tobacco and cigarette smoke therefore help to develop a better understanding of its potential contribution to the health effects associated with tobacco use.
Described within a recently published scientific paper1, scientists at LGC, in collaboration with BAT’s scientists, are using HPLC-ICP-MS2 and an innovative extraction procedure to identify the distribution of various arsenic species within both cut tobacco and cigarette smoke from 3R4F3 research reference cigarettes. Traditionally, the tobacco industry has used mass spectroscopic techniques to quantify total levels of arsenic in tobacco leaf and cigarette smoke.
However, with these techniques the information on identity and quantity of arsenic species in tobacco products could not be obtained due to the very low levels of arsenic (around a few ppm).
Heidi Goenaga-Infante, Principal Scientist at LGC in Mass Spectrometry, said: “It is particularly satisfying that LGC’s significant experience and capability in the area of arsenic and selenium speciation in plant materials has been recognised. By working closely with BAT’s scientists to understand the complex nature of a typical tobacco product, we have successfully developed a new method for determining arsenic species in tobacco and tobacco samples.”
Determining arsenic species in tobacco and tobacco smoke presented LGC’s scientists with several challenges including the requirement for low level detection, the complex smoke and tobacco matrix environment and the propensity of arsenic species to change in chemical form during sample preparation.
Dr Kevin McAdam, Principal Scientist at British American Tobacco commented: “Identifying the chemical forms of arsenic in tobacco products is a step forward in improving our understanding of the composition of tobacco and cigarette smoke. Following the success of this study, BAT is now extending our collaboration with LGC to identify other metal species within tobacco smoke.”
As the UK’s designated National Measurement Institute for chemical and bioanalytical measurement, LGC uses world-class measurement science to develop and improve analytical measurement techniques and documentary standards to support industry in complying with legislation.
1 Determination of total arsenic and arsenic speciation in tobacco products: from tobacco leaf and cigarette smoke, Sutthinun Taebunpakul, Chuan Liu, Christopher Wright, Kevin McAdam, Julien Heroult, Julian Braybrook and Heidi Goenaga-Infante, J. Anal. At. Spectrom., 2011, DOI: 10.1039/C0JA00268B advance article
2 High performance liquid chromatography-inductively coupled plasma mass spectrometry-mass spectrometry
3 R4F Kentucky research reference cigarettes are typical, blended cigarettes containing all major types of tobacco varieties designed as consistent and uniform test items for inhalation toxicology research