19-Norandrosterone, also known as 5α-estran-3α-ol-17-one, is a metabolite of nandrolone (19-nortestosterone) and bolandione (19-norandrostenedione) that is formed by 5α-reductase. It is on the list of substances prohibited by the World Anti-Doping Agency since it is a detectable metabolite of nandrolone, an anabolic-androgenic steroid (AAS).[1] Consumption of androstendione products contaminated with traces of bolandione may also result in testing positive for nandrolone.[2]
Traces of 19-norandrosterone may be naturally present in human urine. An experiment conducted on athletes showed that after a prolonged intense effort, the 19-norandrosterone concentration can be increased by a factor varying between 2 and 4,[3] but another study failed to replicate the result.[4] Concentration also increases in the urine of female athletes during menstruation.[5] The consumption of edible parts of a non-castrated pig, containing 19-nortestosterone, has been shown to result in the excretion of 19-norandrosterone in the following hours, so athletes should prudently avoid meals composed of pig offal in the hours preceding doping tests.[6] Consumption of boar meat, liver, kidneys and heart also increased 19-norandrosterone output.[7]
^Le Bizec B, Monteau F, Gaudin I, André F (February 1999). "Evidence for the presence of endogenous 19-norandrosterone in human urine". J. Chromatogr. B. 723 (1–2): 157–72. doi:10.1016/S0378-4347(98)00541-6. PMID10080643.
^Van Eenoo P, Delbeke FT, de Jong FH, De Backer P (October 2001). "Endogenous origin of norandrosterone in female urine: indirect evidence for the production of 19-norsteroids as by-products in the conversion from androgen to estrogen". J. Steroid Biochem. Mol. Biol. 78 (4): 351–7. doi:10.1016/S0960-0760(01)00112-1. PMID11717005. S2CID19065089.
^Le Bizec B, Gaudin I, Monteau F, Andre F, Impens S, De Wasch K, De Brabander H (2000). "Consequence of boar edible tissue consumption on urinary profiles of nandrolone metabolites. I. Mass spectrometric detection and quantification of 19-norandrosterone and 19-noretiocholanolone in human urine". Rapid Commun. Mass Spectrom. 14 (12): 1058–65. doi:10.1002/1097-0231(20000630)14:12<1058::AID-RCM991>3.0.CO;2-7. PMID10861987.