Analysis of 20 elements in aerosols by inductively coupled plasma mass spectrometry (ICP-MS)
Metals are present in the aerosol of tobacco products and are known as harmful or potentially harmful compounds.
The purpose of this study was to improve and re-validate an existing method for the determination of elements in smoke from cigarettes and in aerosol from potential reduced-risk products (RRPs). In addition, the scope of the method was extended to additional elements in order to cover additional needs related to RRPs and electronic cigarettes.
The method comprises the determination of 20 elements (Aluminium, Arsenic, Beryllium, Cadmium, Calcium, Chromium, Cobalt, Copper, Iron, Lead, Magnesium, Manganese, Molybdenum, Nickel, Selenium, Strontium, Tin, Titanium, Tungsten, Zinc) using an inductively coupled plasma with a mass spectrometer detection (ICP-MS).
Kentucky reference cigarettes 3R4F mainstream smoke and RRPs (tobacco heating systems/THS) mainstream aerosol are generated under Health Canada and ISO smoking regimes and e-cigarettes mainstream aerosol under CORESTA smoking regimes on a rotary machine. The mainstream smoke or aerosol is collected in a quartz electrostatic precipitation tube placed in an electrostatic precipitation unit followed by a micro impinger containing nitric acid 65 %. After aerosol collection, the electrostatic precipitation tube is extracted with nitric acid, which is combined with the nitric acid from the micro impinger and mineralised by microwave. Then, samples are diluted and analysed by ICP-MS.
The addition of a micro impinger allows the collection of elements in gas phase such as arsenic and selenium. For cigarettes, the gas phase represents approximatively 29 % of the total concentration of arsenic and 47 % of the total concentration of selenium.
The method was validated according to ICH guidelines and validation results showed the selectivity, precision, accuracy and linearity over different ranges of concentration depending of the element (in pg/mL).
The calculation of the limit of quantifications (LOQs) for the 20 elements was also reviewed and calculated based on smoked blank variability.
 Reduced-Risk Products (RRPs) is the term used to refer to products that present, are likely to present, or have the potential to present less risk of harm to smokers who switch to these products versus continued smoking.