Li Zheng, Romanoff Lovisa C, Trinidad Debra A, Pittman Erin N, Hilton Donald, Hubbard Kendra, Carmichael Hasan, Parker Jonathan, Calafat Antonia M, Sjödin Andreas
Centers for Disease Control and Prevention, National Center for Environmental Health, Division of Laboratory Sciences, 4770 Buford Highway F-53, Atlanta, GA, 30341, USA,
Anal Bioanal Chem. 2014 May;406(13):3119-29. doi: 10.1007/s00216-014-7676-0. Epub 2014 Apr 9.
Polycyclic aromatic hydrocarbons (PAHs) and their alkylated derivatives, such as methylnaphthalenes (MeNs), are harmful pollutants ubiquitously present in the environment. Exposure to PAHs has been linked to a variety of adverse health effects and outcomes, including cancer. Alkyl PAHs have been proposed as petrogenic source indicators because of their relatively high abundance in unburned petroleum products. We report a method to quantify 11 urinary methylnaphthols (Me-OHNs), metabolites of 1- and 2-methylnaphthalenes, and 10 monohydroxy PAH metabolites (OH-PAHs), using automated liquid-liquid extraction and isotope dilution gas chromatography tandem mass spectrometry (GC-MS/MS). After spiking urine (1 mL) with (13)C-labeled internal standards, the conjugated target analytes were hydrolyzed enzymatically in the presence of ascorbic acid. Then, their free species were preconcentrated into 20 % toluene in pentane, derivatized and quantified by GC-MS/MS. The 11 Me-OHNs eluted as 6 distinct chromatographic peaks, each representing 1 - 3 isomers. Method detection limits were 1.0- 41 pg/mL and the coefficients of variation in quality control materials were 4.7 - 19 %. The method was used to analyze two National Institute of Standards and Technology's Standard Reference Materials® and samples from 30 smokers and 30 non-smokers. Geometric mean concentrations were on average 37 (Me-OHNs) and 9.0 (OH-PAHs) fold higher in smokers than in non-smokers. These findings support the usefulness of Me-OHNs as potential biomarkers of non-occupational exposure to MeNs and sources containing MeNs.
多环芳烃（PAHs）及其烷基化衍生物，如甲基萘（MeNs），是环境中普遍存在的有害污染物。接触多环芳烃与多种不良健康影响和后果有关，包括癌症。由于烷基多环芳烃在未燃烧的石油产品中含量相对较高，因此被提议作为石油成因源指标。我们报告了一种使用自动液液萃取和同位素稀释气相色谱串联质谱法（GC-MS/MS）来定量11种尿中甲基萘酚（Me-OHNs，1-甲基萘和2-甲基萘的代谢物）和10种单羟基多环芳烃代谢物（OH-PAHs）的方法。在向尿液（1 mL）中加入（13）C标记的内标后，在抗坏血酸存在下将结合的目标分析物进行酶水解。然后，将其游离形式预浓缩到戊烷中的20％甲苯中，进行衍生化并通过GC-MS/MS进行定量。11种Me-OHNs以6个不同的色谱峰洗脱，每个色谱峰代表1-3种异构体。方法检测限为1.0-41 pg/mL，质量控制材料中的变异系数为4.7-19％。该方法用于分析两种美国国家标准与技术研究院的标准参考物质®以及来自30名吸烟者和30名非吸烟者的样本。吸烟者中几何平均浓度平均比非吸烟者高37倍（Me-OHNs）和9.0倍（OH-PAHs）。这些发现支持了Me-OHNs作为非职业性接触MeNs和含MeNs来源的潜在生物标志物的有用性。
