Richardot William H, Hamzai Laila, Ghukasyan Tigran, Dodder Nathan G, Quintana Penelope Je, Matt Georg E, Sant Karilyn E, Lopez-Galvez Nicolas, Hoh Eunha
School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA; San Diego State University Research Foundation, 5250 Campanile Dr., San Diego, CA, 92182, USA.
School of Public Health, San Diego State University, 5500 Campanile Dr, San Diego, CA, 92182-4162, USA.
Chemosphere. 2024 Mar;352:141138. doi: 10.1016/j.chemosphere.2024.141138. Epub 2024 Jan 23.
Thirdhand smoke (THS) is the persistent and toxic residue from tobacco smoke in indoor environments. A comprehensive understanding of the chemical constituents of THS is necessary to assess the risks of long-term exposure and to establish reliable THS tracers. The objective of this study was to investigate compounds associated with THS through nontargeted analysis (NTA) of settled house dust samples from smokers' and non-smokers' homes, using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/TOF-MS). Compounds that were either only present in dust from smokers' homes or that had significantly larger abundance than in non-smokers' homes were termed qualified compounds. We identified 140 qualified compounds, and of these, 42 compounds were tentatively identified by searching matching mass spectra in NIST electron impact (EI) mass spectral library including 20 compounds confirmed with their authentic standards. Among the 42 compounds, 26 compounds were statistically more abundant (p < 0.10) in dust from homes of smokers; seven were tobacco-specific compounds, two of which (nornicotyrine, 3-ethenylpyridine) have not been reported before in house dust. Two compounds, tris (2-chloroethyl) phosphate (a toxic compound used as a flame retardant and reported in tobacco) and propanoic acid, 2-methyl-, 1-(1,1-dimethylethyl)-2-methyl-1,3-propanediyl ester (highly abundant and reported in exhaled air of smokers), were found in dust from all smokers' homes and in zero non-smokers' homes, making these potential THS tracers, possibly associated with recent smoking. Benzyl methyl ketone was significantly higher in dust in smokers' homes, and was previously reported not as a product of tobacco but rather as a form of methamphetamine. This compound was recently reported in mainstream tobacco smoke condensate through NTA as well. These identified potential tracers and chemical components of THS in this study can be further investigated for use in developing THS contamination and exposure assessments.
三手烟（THS）是室内环境中烟草烟雾的持久性有毒残留物。全面了解三手烟的化学成分对于评估长期接触风险以及建立可靠的三手烟追踪指标至关重要。本研究的目的是通过对吸烟者和非吸烟者家中的沉降屋尘样本进行非靶向分析（NTA），利用全二维气相色谱-飞行时间质谱联用仪（GC×GC/TOF-MS）来研究与三手烟相关的化合物。仅存在于吸烟者家中灰尘中或其丰度明显高于非吸烟者家中灰尘的化合物被称为合格化合物。我们鉴定出了140种合格化合物，其中42种化合物通过在NIST电子轰击（EI）质谱库中搜索匹配质谱进行了初步鉴定，包括20种用其标准品确认的化合物。在这42种化合物中，有26种化合物在吸烟者家中灰尘中的含量在统计学上更高（p < 0.10）；7种是烟草特异性化合物，其中两种（降烟碱、3-乙烯基吡啶）此前尚未在屋尘中报道过。两种化合物，磷酸三（2-氯乙基）酯（一种用作阻燃剂的有毒化合物，在烟草中也有报道）和2-甲基丙酸1-（1,1-二甲基乙基）-2-甲基-1,3-丙二醇酯（含量很高，在吸烟者呼出的空气中也有报道），在所有吸烟者家中的灰尘中都有发现，而在非吸烟者家中的灰尘中均未发现，这使得它们成为潜在的三手烟追踪指标，可能与近期吸烟有关。苯乙酮在吸烟者家中灰尘中的含量明显更高，此前报道它不是烟草产物，而是甲基苯丙胺的一种形式。最近通过非靶向分析也在主流烟草烟雾冷凝物中报道了这种化合物。本研究中鉴定出的这些潜在的三手烟追踪指标和化学成分可进一步研究，用于开展三手烟污染和暴露评估。
