Probing Tobacco-Specific Nitrosamines on Indoor Surfaces Using Chemical Ionization Mass Spectrometry

Tobacco-specific nitrosamines (TSNAs) are carcinogenic compounds that can form during chemical aging of thirdhand smoke (THS) on indoor surfaces, increasing health risks over time for smokers and nonsmokers. This study presents a sensitive and effective method for detecting and quantifying nicotine and TSNAs from THS on various indoor surfaces using protonated ethanol-based thermal desorption chemical ionization mass spectrometry (TD-CIMS). This analytical method demonstrates a detection limit on the order of 10 pg for nicotine and TSNAs. Three common TSNAs in textile samples from laboratory chamber experiments and smokers’ homes are successfully identified and quantified, including N′-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and 4-(N-methyl-N-nitrosamino)-4-(3-pyridyl)butanal (NNA). The results show that textile indoor surfaces can retain up to 58 mg m^–2 nicotine and 11.7 mg m^–2 TSNAs long after tobacco use has ceased. We also report that indoor textile surfaces, and especially carpets, can serve as a deep reservoir for TSNAs where they may accumulate to concentrations comparable to that of nicotine, significantly higher than previously thought. These findings suggest that textile surfaces in THS-exposed indoor environments serve as both a reservoir and long-term source of harmful tobacco-related chemicals.