Development of a method which discriminates between endogenous and exogenous beta-boldenone.
One potential explanation for the presence of beta-boldenone in calf urine is contamination of the sample with feces containing beta-boldenone. It has been demonstrated that after oral and intramuscular administration of beta-boldenone esters, several metabolites are formed and excreted in urine. One of the (minor) metabolites is 6beta-hydroxy-17alpha-boldenone. This paper describes an analytical method that can discriminate between unconjugated boldenone, its glucuronide- and sulphate-conjugates, 6beta-hydroxy-17alpha/beta-boldenone and coprostanol, a marker for fecal contamination. The method was applied to all samples suspected to contain boldenone within the Dutch National Residue Control Plan. Approximately 10,000 samples of urine were screened (LC-MS) in 2004-2005 by VWA-East, one of the official Dutch control laboratories, from which 261 samples were suspected to contain boldenone. These samples were all analyzed for their conjugation state, 6beta-hydroxy-17alpha/beta-boldenone and for the presence of coprostanol. Alfa-boldenone, the major metabolite in bovine urine after boldenone-ester administration, was found in a large number of these samples. The presence of alpha-boldenone was proven also to be a result of fecal contamination. None of the samples tested contained residues of the metabolite 6beta-hydroxy-17alpha/beta-boldenone. Not finding this metabolite indicates that the origin of alpha-boldenone-conjugates is endogenous. The results confirm that the presence of unconjugated beta-boldenone and alpha-boldenone conjugates next to alpha-boldenone are no indicators for illegal administration of boldenone-esters. No indications were obtained that conjugated beta-boldenone can be of endogenous origin.
Blokland
M H
MH
National Institute of Public Health and the Environment (RIVM), European Union Community Reference Laboratory for Residues, P.O. Box 1, NL-3720 BA Bilthoven, The Netherlands. marco.blokland@rivm.nl
van Rossum
H J
HJ
Sterk
S S
SS
van Ginkel
L A
LA
Stephany
R W
RW
D045930:Anabolic Agents / Q000032:analysis* / Q000652:urine*; D000818:Animals; D002417:Cattle; D002623:Chemistry Techniques, Analytical; D004083:Cholestanol / Q000652:urine; D002849:Chromatography, Gas / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods; D005243:Feces; D020719:Glucuronides / Q000032:analysis; D013058:Mass Spectrometry / Q000379:methods; D009426:Netherlands; D015203:Reproducibility of Results; D013739:Testosterone / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry / Q000652:urine; D016482:Urinalysis / Q000379:methods*
D045930:Anabolic Agents; D020719:Glucuronides; D013739:Testosterone; C013915:boldenone; D004083:Cholestanol