title: Quantitation of urinary volatile nitrosamines from exposure to tobacco smoke.
abstract: A sensitive and selective method was developed and validated to detect six volatile nitrosamines (N-nitrosodimethylamine, N-nitrosomethylethylamine, N-nitrosodiethylamine, N-nitrosopiperidine, N-nitrosopyrrolidine and N-nitrosomorpholine) in human urine. This method uses a liquid-liquid extraction cartridge followed by analysis with gas chromatography-tandem mass spectrometry (GC-MS-MS) and quantification based on isotopic dilution. This is the first GC-MS-MS method reported for measuring volatile nitrosamines in human urine. This method reduces the sample volume required in other methods from 5-25 to 2 mL. The limits of detection (2.62, 1.99, 2.73, 0.65, 0.25, 3.66 pg/mL, respectively) were better than existing methods, largely because of improved positive chemical ionization achieved by using ammonia gas and reducing background noise. Using nitrogen as the collision gas allowed the confirmation transition in the low mass region to be monitored. The analysis of human urine using this validated method is accurate (relative bias of 0-19%) and precise (relative standard deviation of 0.2-18% over two months of analyses). The validated method was applied to 100 urine samples and the levels of all six volatile nitrosamines were reported for the first time in urine specimens collected from smokers and nonsmokers, with smoking status determined by urinary cotinine measurement. Among 100 smokers and nonsmokers, the levels of three analytes (N-nitrosodimethylamine, N-nitrosomethylethylamine and N-nitrosopiperidine) were significantly higher in smokers than nonsmokers (p < 0.05).
authors.affiliation: Tobacco and Volatiles Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA. tvh2@cdc.gov
authors.forename: Tiffany H
authors.initials: TH
authors.lastname: Seyler
authors.forename: Jenny G
authors.initials: JG
authors.lastname: Kim
authors.forename: James A
authors.initials: JA
authors.lastname: Hodgson
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Cowan
authors.forename: Benjamin C
authors.initials: BC
authors.lastname: Blount
authors.forename: Lanqing
authors.initials: L
authors.lastname: Wang
mesh_terms: D003367:Cotinine / Q000652:urine; D004052:Diethylnitrosamine / Q000652:urine*; D004128:Dimethylnitrosamine / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D059625:Liquid-Liquid Extraction; D009242:N-Nitrosopyrrolidine / Q000032:analysis*; D009602:Nitrosamines / Q000652:urine*; D015203:Reproducibility of Results; D012907:Smoking / Q000652:urine*; D055549:Volatile Organic Compounds / Q000652:urine; D014026:Nicotiana
chemical_list: D009602:Nitrosamines; D055549:Volatile Organic Compounds; D004052:Diethylnitrosamine; C002741:N-nitrosomorpholine; C002743:N-nitrosopiperidine; D003367:Cotinine; D004128:Dimethylnitrosamine; D009242:N-Nitrosopyrrolidine