Validation of an HPLC-MS/MS method for the simultaneous determination of phenylmercapturic acid, benzylmercapturic acid and o-methylbenzyl mercapturic acid in urine as biomarkers of exposure to benzene, toluene and xylenes.
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and fully validated, according to U.S. Food and Drug Administration guidance, for the simultaneous determination of phenylmercapturic acid, benzylmercapturic acid and o-methylbenzyl mercapturic acid in human urine as biomarkers of exposure to benzene, toluene and xylenes (BTX). After solid phase extraction and LC separation, samples were analyzed by a triple-quadrupole mass spectrometer operated in negative ion mode, using isotope-labeled analogs as internal standards (ISs). The method meets all the validation criteria required. The limits of detection of the three analytes, ranging from 0.30 to 0.40microgl(-1), and the high throughput make the method suitable for the routine biological monitoring of co-exposure to BTX both in the occupational and environmental settings. The validated method was applied to assess exposure to BTX in a group of 354 urban traffic wardens.
Sabatini
Laura
L
Occupational Medicine Unit, University of Bologna, S. Orsola-Malpighi Hospital, via Palagi 9, 40138 Bologna, Italy. l.sabatini@unibo.it
Barbieri
Anna
A
Indiveri
Paolo
P
Mattioli
Stefano
S
Violante
Francesco Saverio
FS
D000111:Acetylcysteine / Q000031:analogs & derivatives* / Q000652:urine*; D001554:Benzene / Q000032:analysis; D015415:Biomarkers / Q000652:urine; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007202:Indicators and Reagents; D016273:Occupational Exposure; D011786:Quality Control; D015203:Reproducibility of Results; D012997:Solvents / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization; D014050:Toluene / Q000032:analysis; D014992:Xylenes / Q000032:analysis
D015415:Biomarkers; D007202:Indicators and Reagents; D012997:Solvents; D014992:Xylenes; D014050:Toluene; C053003:S-phenyl-N-acetylcysteine; D001554:Benzene; D000111:Acetylcysteine; C029319:S-benzyl-N-acetyl-L-cysteine