title: Stereometabolism of ethylbenzene in man: gas chromatographic determination of urinary excreted mandelic acid enantiomers and phenylglyoxylic acid and their relation to the height of occupational exposure.
abstract: Ethylbenzene is an important industrial solvent and a key substance in styrene production. Ethylbenzene metabolism leads to the formation of mandelic acid, which occurs in two enantiomeric forms, and phenylglyoxylic acid. To decide which enantiomer is preferably formed, 70 urine samples of exposed workers were taken at the end of shifts and--after 3-pentyl ester derivatisation--gas chromatographically analysed. The R/S ratio of mandelic acid enantiomers in urine amounts to 19:1, which means that R-mandelic acid is a major metabolite and S-mandelic acid is one of the minor urinary metabolites of ethylbenzene in man. The R/S ratio is independent of ambient air concentration of ethylbenzene within the investigated range. Compared to an ethylbenzene monoexposure the height of total mandelic acid excretion is decreased in the case of coexposure to other aromatic solvents.
authors.affiliation: Institut für Arbeits- und Sozialmedizin Universität Tübingen, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Korn
authors.forename: W
authors.initials: W
authors.lastname: Gfrörer
authors.forename: R
authors.initials: R
authors.lastname: Herz
authors.forename: I
authors.initials: I
authors.lastname: Wodarz
authors.forename: R
authors.initials: R
authors.lastname: Wodarz
mesh_terms: D001555:Benzene Derivatives / Q000378:metabolism*; D002617:Chemical Industry; D002849:Chromatography, Gas; D006038:Glyoxylates / Q000652:urine*; D006801:Humans; D008333:Mandelic Acids / Q000737:chemistry / Q000652:urine*; D016273:Occupational Exposure / Q000032:analysis*; D010150:Paint; D012997:Solvents / Q000378:metabolism*; D013237:Stereoisomerism
chemical_list: D001555:Benzene Derivatives; D006038:Glyoxylates; D008333:Mandelic Acids; D012997:Solvents; C012482:phenylglyoxylic acid; C004912:ethylbenzene; C037938:mandelic acid