title: Rapid determination of four short-chain alkyl mercapturic acids in human urine by column-switching liquid chromatography-tandem mass spectrometry.
abstract: We developed and validated an analytical method for the simultaneous determination of methyl mercapturic acid (MeMA), ethyl mercapturic acid (EtMA), n-propyl mercapturic acid (PrMA) and iso-propyl mercapturic acid (iPrMA) in human urine. These alkyl mercapturic acids are known or presumed biomarkers of exposure to several alkylating agents including methyl bromide, dimethyl sulfate, ethyl bromide, 1-bromopropane and 2-bromopropane. The method involves a column switching arrangement for online solid phase extraction of the analytes with subsequent analytical separation and detection using liquid chromatography and tandem mass spectrometry. Within day and day-to-day imprecision was determined to range from 4.5 to 12.2%. The analytical method is distinguished by its wide linear working range of up to 2,500 μg/L with detection limits ranging from 2.0 μg/L (for PrMA) to 5.1 μg/L (for MeMA) that render possible the application in various biomonitoring studies regarding exposure to alkylating agents. The results of a pilot study on urine samples of 30 individuals occupationally non-exposed to alkylating agents using the new procedure confirmed the background excretion of MeMA (<5.1-35.6 μg/L) and PrMA (<2.0-95.7 μg/L).
authors.affiliation: Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schillerstrasse 25/29, 91054 Erlangen, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Eckert
authors.affiliation: Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schillerstrasse 25/29, 91054 Erlangen, Germany. Electronic address: Thomas.Goeen@ipasum.med.uni-erlangen.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Göen
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000652:urine*; D000328:Adult; D000477:Alkylating Agents / Q000737:chemistry / Q000652:urine; D015415:Biomarkers / Q000737:chemistry* / Q000652:urine*; D002853:Chromatography, Liquid / Q000379:methods*; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012907:Smoking; D053719:Tandem Mass Spectrometry / Q000379:methods*; D055815:Young Adult
chemical_list: D000477:Alkylating Agents; D015415:Biomarkers; D000111:Acetylcysteine
keywords: Alkylating agents; Biomonitoring; Carcinogens; LC–MS/MS; Mercapturic acid