Measurement of the urinary metabolites of N-hexane, cyclohexane and their isomers by gas chromatography.

A gas chromatographic method for analyzing the urinary metabolites of n-hexane (2-hexanol, 2,5-hexanedione, 2,5-dimethylfuran and gamma-valerolactone), of 2-methylpentane (2-methyl-2-pentanol), of 3-methylpentane (3-methyl-2-pentanol), and of cyclohexane (cyclohexanol) was developed. Processing of urine and the gas chromatographic conditions are described. The recovery rate of all hexane metabolites, except 2,5-dimethylfuran, ranged between 92 and 100%. The variation coefficient of metabolites determination was between 1.5 and 5%, apart from 2.5-dimethylfuran determination for which the variation coefficient was 15%. The detection limits ranged between 0.2 and 0.7 mg/l and between 0.05 and 0.1 mg/l when a packed or capillary column was used. Results obtained from a packed and capillary column are discussed.