Using liquid chromatography-tandem mass spectrometry to quantify monohydroxylated metabolites of polycyclic aromatic hydrocarbons in urine.
We present an assay which employs enzyme digestion and solid phase extraction followed by liquid chromatography-tandem mass spectrometry to simultaneously quantify 16 hydroxylated polycyclic aromatic hydrocarbons (OHPAHs) in 3-ml samples of urine. The analytes consisted of 2-, 3-, and 4-ring OHPAHs, namely, 1- and 2-hydroxynaphthalene (1- and 2-OHNAP), 2-hydroxyfluorine (2-OHFLU), 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene (1-, 2-, 3-, 4-, and 9-OHPHE), 1-hydroxypyrene (1-OHPYR), 1- and 2-hydroxybenzo(a)anthracene (1- and 2-OHBAA), 3- and 6-hydroxychrysene (3- and 6-OHCHR) and 3-, 7-, and 9-hydroxybenzo(a)pyrene (3-, 7-, and 9-OHBAP). The method was validated using urine samples from steel workers and control subjects. The coefficients of variation of the method for the particular analytes were between 7% and 27% and the limits of quantitation were between 0.002 and 0.010 microg/l urine. The 2- and 3-ring OHPAHs were easily quantified in all subjects. However, 1-OHPYR was the only representative of the 4- and 5-ring metabolites that could be quantified. Pairwise correlations showed that all OHPAHs were highly correlated with each other (0.553<or=r<or=0.910) and with 1-OHPYR (0.614<or=r<or=0.910), the metabolite most widely accepted as a short-term biomarker of exposure to PAHs. The analyte, 2-OHNAP exhibited the lowest pairwise correlations with the other OHPAHs (0.542<or=r<or=0.628), presumably due to confounding by smoking. Metabolites of phenanthrene, an abundant PAH and the smallest to possess a bay region, are promising OHPAHs for characterizing both exposures to PAHs and the various metabolic pathways.
Onyemauwa
Frank
F
Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431, USA.
Rappaport
Stephen M
SM
Sobus
Jon R
JR
Gajdosová
Dagmar
D
Wu
Ren'an
R
Waidyanatha
Suramya
S
D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D006900:Hydroxylation; D007202:Indicators and Reagents; D008669:Metallurgy; D016273:Occupational Exposure / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000652:urine*; D015203:Reproducibility of Results; D013232:Steel; D053719:Tandem Mass Spectrometry
D007202:Indicators and Reagents; D011084:Polycyclic Aromatic Hydrocarbons; D013232:Steel