Detection of mono-hydroxylated metabolites of stanozolol by HPLC-ESI (+) MS/MS in Indian sports persons

The abuse of stanozolol is quite widespread in Indian sport. Its analysis is challenging and this has led to the development of new methods to improve its detection. A method was developed and validated for the detection of the three main monohydroxylated metabolites of stanozolol. The excretion profile of these metabolites was studied in four healthy male volunteers. The excretion study samples, after a single oral dose of drug, showed that 3'-OH-stanozolol was excreted at the highest concentration, followed by 16 beta-OH stanozolol, with 4 beta-OH stanozolol as the least excreted. Ninety-eight old doping samples with adverse analytical findings for 3'-OH-stanozolol were reanalysed using this method. This showed 3'-OH-stanozolol and 16 beta-OH stanozolol in all the 98 samples whereas 4 beta-OH-stanozolol was identified in 90 samples. The percentage of positive identifications of stanozolol in Indian sportspeople has increased markedly in the last five years, from 31.9% in 2004 to 81.8% in 2009; however, this may be due to the more effective detection of stanozolol metabolites. It can thus be concluded that the marked increase in percent positive of stanozolol in Indian sportspersons in 2009 may be due to the improved detection by a more effective LCMS/MS method. Copyright (C) 2010 John Wiley & Sons, Ltd.