title: A column-switching liquid chromatography-tandem mass spectrometry method for quantitation of 2-cyanoethylmercapturic acid and 2-hydroxyethylmercapturic acid in Chinese smokers.
abstract: The acrylonitrile metabolites 2-cyanoethylmercapturic acid (CEMA) and 2-hydroxyethylmercapturic acid (HEMA) have been determined in human urine using an automated column-switching procedure. A diluted sample was centrifuged just prior to being injected into a reusable precolumn packed with a restricted access material and coupled to a liquid chromatography-tandem mass spectrometry system. This method achieved satisfactory reproducibility and accuracy. Average intra- and interday variations (% relative standard deviations) ranged from 2.4 to 3.8% for CEMA and from 2.7 to 10.5% for HEMA. The limits of quantification were 0.003 and 0.099ng/ml for CEMA and HEMA, respectively. It was used to study the uptake of acrylonitrile from smoke constituents by both nonsmokers and smokers of different tar yield cigarettes under ISO 3308 smoking condition. Metabolite concentrations in smoker urine samples were approximately 12 times higher compared with those in nonsmokers for CEMA and 3 times higher for HEMA. Urinary CEMA levels show a clear dose-response relationship with daily cigarette consumption and urinary cotinine. CEMA can also discriminate between smokers of different ISO cigarettes. Because HEMA is not specific, it is only slightly related to smoking and acrylonitrile exposure. The validated biomarker CEMA will continue to be useful for studies of acrylonitrile uptake by smokers.
authors.affiliation: China National Tobacco Quality Supervision and Test Center, Zhengzhou High and New Technology Industries Development Zone, Zhengzhou, People's Republic of China. houhw@ztri.com.cn
authors.forename: Hongwei
authors.initials: H
authors.lastname: Hou
authors.forename: Wei
authors.initials: W
authors.lastname: Xiong
authors.forename: Na
authors.initials: N
authors.lastname: Gao
authors.forename: Xiaotao
authors.initials: X
authors.lastname: Zhang
authors.forename: Gangling
authors.initials: G
authors.lastname: Tang
authors.forename: Qingyuan
authors.initials: Q
authors.lastname: Hu
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000652:urine; D000181:Acrylonitrile / Q000378:metabolism / Q000494:pharmacology; D000328:Adult; D044466:Asian People; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008875:Middle Aged; D015203:Reproducibility of Results; D012907:Smoking / Q000378:metabolism / Q000652:urine*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013997:Time Factors; D016482:Urinalysis / Q000379:methods*; D055815:Young Adult
chemical_list: C031104:N-acetyl-S-(2-hydroxyethyl)cysteine; D000181:Acrylonitrile; C025645:N-acetyl-S-(2-cyanoethyl)cysteine; D000111:Acetylcysteine