We developed a gas chromatography/isotope dilution high- resolution mass spectrometry (GC/ID-HRMS) method for measuring 18 PAH metabolites representing 8 parent PAHs in 3 mL of urine at low part-per-trillion levels. We applied this method to the analysis of urine specimens from approximately 2400 people who participated in the National Health and Nutrition Examination Survey for the years 1999 and 2000 to determine levels for 14 PAH hydroxy metabolites of 7 parent compounds. Using this GC/ID-HRMS method, we found detectable concentrations for monohydroxy metabolite isomers of fluorene, phenanthrene, fluoranthene, and pyrene, and for chrysene, benzo[c]phenanthrene, and benz[a]anthracene. Some monohydroxy metabolite isomers of chrysene, benzo[c]phenanthrene, and benz[a]anthracene exhibited low detection frequencies which did not allow for geometric mean calculations. From our study, we established a reference range for the targeted PAHs in the general U.S. population.