Determination of Phenols and Cresols in Urine by Gas Chromatography

Abstract
A rapid, simple, and sensitive method was developed for the determination of three cresol isomers and phenol in urine. The sample was spiked with m-chlorophenol, as internal standard, and hydrolyzed with sulfuric acid at ambient temperature. The hydrolyzed solution was saturated with ammonium sulfate and extracted with ethyl acetate. The extract was injected without derivatization into a gas chromatograph fitted with a flame ionization detector and a glass column packed with 0.1% SP 1000 on Carbopack C. All four analytes, which eluted within 13 minutes, were quantified from standard curves. The method was evaluated by analysis of spiked urine pools from laboratory workers and samples of urine from workers in a coal gasification plant.