Quantification and Profiling of 19-Norandrosterone and 19-Noretiocholanolone in Human Urine after Consumption of a Nutritional Supplement and Norsteroids

Quantification and Profiling of 19-Norandrosterone and 19-Noretiocholanolone in Human Urine after Consumption of a Nutritional Supplement and Norsteroids / Ying Lung Tseng, Fan-Hsin Kuo, Kuo-Hu Sun. - (Journal of Analytical Toxicology 29 (2005) 2 (March); p. 124-134)

  • PMID: 15902981
  • DOI: 10.1093/jat/29.2.124


Nandrolone is one of the synthetic anabolic steroids banned in sports and has been a popular substance abused by athletes in recent years. One of its major metabolites, 19-norandrosterone (19-NA), has been used as a determinant for drug violations in sports. Current reports regarding nandrolone-positive cases have been related to intake of some nandrolone-free nutritional supplements. The aim of this study was to learn whether if a nutritional supplement sold by over-the-counter (OTC) nutritional stores could yield the same metabolic products as that of nandrolone. If so, what is (are) the substance(s) that contributed to the nandrolone metabolites? To determine the content of an OTC nutritional supplement, a tablet was dissolved in methanol, followed by N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA)-trimethyliodosilane (TMIS) derivatization prior to gas chromatography-mass spectrometry (GC-MS) analysis. The collected urine samples underwent extraction, enzymatic hydrolysis, and derivatization before the analyses of GC-MS. The results showed that seven anabolic steroids were found as contaminants in the nutritional supplement, in addition to six that were listed in the ingredients by the manufacturer. We confirmed previous reports that administration of the OTC supplement could produce a positive urine test for nandrolone metabolites. Furthermore, the results from excretion studies showed that 19-NA and 19-noretiocholanolone (19-NE) were present in urine after consuming the nutritional supplement, nandrolone, 19-nor-4-androsten-3,17-dione, 19-nor-4-androsten-3beta,17beta-diol, and 19-nor-5-androsten-3beta,17beta-diol. The 19-NA concentrations in urine were generally higher than that of 19-NE (19-NA/19-NE ratio > 1.0) especially during the early stage of excretion, that is, before 6 h post-administration. After this period of time, the concentrations of 19-NA and 19-NE fluctuated and might even have reversed (19-NA/19-NE ratio < 1.0) in their ratio, that is, higher yield in 19-NE than that in 19-NA. On the basis of this study, we postulate that some doping violations of nandrolone could be attributed by indiscriminate administration of the OTC nutritional supplements that contained 19-norsteroids.

Original document


Research / Study
1 March 2005
Kuo, Fan-Hsin
Sun, Kuo-Hu
Tseng, Ying Lung
Adverse Analytical Finding / presence
Other organisations
Tzu Chi University (TCU)
Analytical aspects
Mass spectrometry analysis
Doping classes
S1. Anabolic Agents
Nandrolone (19-nortestosterone)
Document category
Scientific article
Document type
Pdf file
Date generated
2 July 2019
Date of last modification
7 September 2020
  • Legal Source
  • Education
  • Science
  • Statistics
  • History
Country & language
  • Country
  • Language
Other filters
  • ADRV
  • Legal Terms
  • Sport/IFs
  • Other organisations
  • Laboratories
  • Analytical aspects
  • Doping classes
  • Substances
  • Medical terms
  • Various
  • Version
  • Document category
  • Document type
Publication period