title: Di(2-ethylhexyl) phthalate metabolites as markers for blood transfusion in doping control: intra-individual variability of urinary concentrations.
abstract: To indicate homologous or autologous blood transfusion in sports drug testing, quantification of increased urinary concentrations of di(2-ethylhexyl) phthalate (DEHP) metabolites presents a promising approach; however, the possible intra-individual variation of the metabolite concentrations over time has not been well characterized. The aim of this study was to explore the intra-individual variability of urinary DEHP metabolites among seven volunteers without special occupational exposure to DEHP during one week (n = 253) in order to investigate the possibility of increased urinary concentrations of the metabolites caused by, for example, residential, dietary, or environmental exposure. Quantification of three DEHP metabolites--mono(2-ethylhexyl) phthalate, mono(2-ethyl-5-oxohexyl) phthalate, and mono(2-ethyl-5-hydroxyhexyl) phthalate--was accomplished after enzymatic hydrolysis of urinary glucuronide conjugates and direct injection using isotope-dilution liquid chromatography-tandem mass spectrometry. Although urinary concentrations of DEHP metabolites showed considerable intra-individual variation, no increased values were observed comparable to the concentrations measured in urine specimens collected after blood transfusion.
authors.affiliation: Joint Research and Training Laboratory on Separation Techniques, Eötvös Loránd University, Budapest, Hungary.
authors.forename: E
authors.initials: E
authors.lastname: Solymos
authors.forename: S
authors.initials: S
authors.lastname: Guddat
authors.forename: H
authors.initials: H
authors.lastname: Geyer
authors.forename: A
authors.initials: A
authors.lastname: Thomas
authors.forename: M
authors.initials: M
authors.lastname: Thevis
authors.forename: W
authors.initials: W
authors.lastname: Schänzer
mesh_terms: D000328:Adult; D001803:Blood Transfusion; D002853:Chromatography, Liquid; D004051:Diethylhexyl Phthalate / Q000378:metabolism* / Q000652:urine*; D004300:Doping in Sports; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D015813:Substance Abuse Detection
chemical_list: D004051:Diethylhexyl Phthalate