Development and validation of a method for quantification of two tobacco-specific nitrosamines in indoor air

• Published in: Journal of Chromatography A 2018-12, Vol.1580, p.90-99
• Main Authors: Gómez Lueso, María, Mitova, Maya I., Mottier, Nicolas, Schaller, Mathieu, Rotach, Michel, Goujon-Ginglinger, Catherine G.
• Format: Article
• Language: English
• Subjects: Accuracy profile; e-Cigarette; Environmental aerosol; Tobacco heating system; Tobacco-specific nitrosamines; Validation
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2018.10.037

•Novel trapping technique and high throughput method for NNN and NNK determination.•Accurate quantification of NNN and NNK in indoor air in ng/m3- pg/m3 range.•Validation with accuracy profiles to assess matrix effects on quantifications.•Evaluation of the impact on indoor air of THS 2.2, e-cigarettes and cigarettes. A sensitive and accurate method for the quantification of 1′-Demethyl-1′-nitrosonicotine (NNN) and 4-(methylnitrosamino)-1-(3-Pyridyl)-1-butanone (NNK) in indoor air was developed and validated. To this aim, a novel approach for the collection of two tobacco-specific nitrosamines, using silica sorbent cartridges followed by simplified sample preparation and isotope dilution liquid chromatography/electrospray ionization tandem mass spectrometry, was applied. This procedure led to a substantial improvement in terms of sensitivity and sample throughput as compared with methods using conventional trapping. For the validation, a matrix-based approach using an accuracy profile procedure was selected. The evaluated matrices were background air samples, environmental aerosols of a heat-not-burn tobacco product (Tobacco Heating System [THS] 2.2, commercialized under the brand IQOS®), a rechargeable electronic cigarette (Solaris®), and the environmental tobacco smoke (ETS) of a conventional cigarette (Marlboro Gold®). The method showed excellent recoveries, sensitivity, and precision. The limits of detection of the method for NNN and NNK were 0.0108 ng/m3 and 0.0136 ng/m3, respectively. The calibration range of the instrument spanned 0.2–60 ng/mL. The calculated lower working range limit (LWRL) of the method for NNN was 0.126 ng/m3, and the LWRL for NNK was 0.195 ng/m3. The method was applied to evaluate surrogate environmental aerosols generated using smoking machines. This model is reliable but gives a large overestimation of the possible impact of THS 2.2 and e-cigarettes on indoor air, because the retention of NNN and NNK in the body of the consumers is not taken into account. As a consequence, the values reported do not reflect a real-life setting. The contents of the two target compounds in the surrogate environmental aerosols were 0.0830 ± 0.0153 ng/m3 of NNN and 0.0653 ± 0.0138 ng/m3 of NNK for THS 2.2, 0.0561 ± 0.0296 ng/m3 of NNN for e-cigarettes, and 0.816 ± 0.109 ng/m3 of NNN and 4.13 ± 1.04 ng/m3 NNK for cigarettes. These values correspond to 10% of the measured ETS concentration for NNN in environmental aerosols of THS 2.2 and 7% for those