: Benzene and its metabolite phenol are extractable from human whole blood and urine using headspace solid-phase microextraction SPME with a Carboxen / polydimethylsiloxane fiber. Both compounds were assayed using ethylbenzene and 2,4-dimethylphenol as internal standards IS and capillary gas chromatography GC with flame ionization detection. The headspace SPME-GC gave sharp peaks for benzene, phenol, and IS-1, 2 ; with the whole blood and urine samples showing low background noise. The extraction ef ciencies of benzene and phenol were 51.8-99.4 and 10.6-14.3 , respectively, for both whole blood and urine. Regression equations also showed excellent linearity in the range of 5-400 ng / 0.5 ml for benzene and 10-500 ng / 0.5 ml for phenol extracted from whole blood and urine. The detection limits signal-to-noise ratio 3 for the benzene and phenol were 5-10 ng / 0.5 ml for whole blood and 2-5 ng / 0.5 ml for urine. The coef cients of within-day variation in terms of extraction ef ciency for both compounds in whole blood and urine samples were not greater than 13.8 . These data indicate that benzene and phenol can be successfully separated and determined from human samples using the established headspace SPME method.