, 2009; Torikaiu, Uwano, Nakamori, Tarora, & Takahashi, 2005). McGrath, Brown, Meruva, and Chan (2009) showed that hydroquinone, catechol, and methyl derivatives of catechol are produced in highest amounts selleckchem Dorsomorphin at tobacco pyrolysis temperatures ��350��C due to their limited thermal stability at higher temperatures. Formation of other phenols such as cresols, phenol, and resorcinol is favored between 350 and 600 ��C. Hence, temperature is considered an essential factor for the formation and the decomposition of many toxins like phenolic compounds in the smoke. The temperature at which the tobacco is heated inside the head of the waterpipe reaches up to 450 ��C (Shihadeh 2003; Shihadeh & Saleh, 2005), whereas the burning temperatures of cigarette tobacco can reach up to 950 ��C (Cz��g��ny et al.

, 2009). Therefore, high levels of phenols and their derivatives are expected in the waterpipe smoke because the smoke is generated at optimal temperatures for phenols production. Many analytic techniques were developed to determine phenols in cigarette smoke (Moldoveanu & Kiser, 2007). The most common techniques are high-performance liquid chromatography (HPLC) with ultra violet or fluorescence detection and capillary gas chromatography with mass spectrometry (GC-MS) (Moldoveanu & Kiser, 2007). In this study, the identification and quantification of phenolic compounds and their derivatives in the particle phase of the mainstream waterpipe smoke was realized using GC-MS selected ion current profile (GC-MS-SICP) chromatogram method after sample derivatization.

EXPERIMENTAL Chemicals A standard mixture of seven phenols (phenol, o-cresol, m-cresol, p-cresol, catechol, resorcinol, and hydroquinone) and a mixture of two deuterated phenols (phenol-d6 and 4-methylphenol- d8) at 1000 ��g/ml each were purchased from Absolute Anacetrapib Standards. Polystyrene divinylbenzene (PS-DVB) SPE cartridges (CHROMABOND?; EASY 200mg, 3ml) were purchased from Sorbent Technology. The derivatizing reagent, bis (trimethylsilyl)-trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS) and HPLC-grade solvents of methanol, dichlomethane, and ethylacetate were purchased from Sigma-Aldrich. Smoke Generation and Collection Mainstream waterpipe smoke was generated and collected in accordance with the Beirut method (Katurji, Daher, Sheheitli, Saleh, & Shihadeh, 2010; Shihadeh & Saleh, 2005) using Nakhla Double Apple (Egypt) waterpipe tobacco preparation and Three Kings (Holland) charcoal. During each machine smoking session, the smoke exiting the waterpipe mouthpiece was split into four parallel branches and each stream drawn through a 47-mm glass fiber filter pad (47mm, Pall Gelman Type A/E). As in Shihadeh et al.