|Abstract Title:||The analysis of steroid seizures from UK customs- Implications for Anti-Doping|
|Presenter Name:||Dr Alan Brailsford|
|Co-authors:||Dr Chris Walker|
Ms Mahirah Majidin
Prof David Cowan
|Company/Organisation:||Kings College London|
|Session Choice:||Advances in Clinical Analysis|
Abstract Information :
INTRODUCTION - The endogenous anabolic and androgenic steroids (EAAS) nandrolone and testosterone remain widely available, both on the internet and through local "dealers". Due to their anabolic properties they continue to be of interest to some athletes who seek to enhance their performance through pharmaceutical means. However, confirming a doping violation resulting from the administration of these steroids can be challenging, due to the natural production of testosterone and the diagnostically important major metabolite of nandrolone (19-norandrosterone). This means that the simple presence of these compounds (at physiological concentrations) cannot be used to infer administration.
Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is used to distinguish between exogenous (synthetic origin) and endogenous (natural origin) steroids based on the carbon isotope ratio (13C/12C). The 13C/12C ratio is dependent on a compounds origin and route of production; therefore synthetically produced steroids may have a different 13C/12C ratio relative to endogenously produced molecules facilitating discrimination between the two.
However, should both endogenous and exogenous sources of the steroid have a similar 13C/12C ratio, GC-C-IRMS analysis would be unable to distinguish between them, meaning the administration of such steroids would go undetected. Such pseudo-endogenous steroid preparations are therefore of great interest to the anti-doping community.
By analysing customs seizures along with pharmaceutical preparations this study investigates the availability and prevalence of steroid preparations which have a similar 13C/12C ratio to endogenous steroids, and therefore may not be detected by GC-C-IRMS analysis following administration.
METHODS - A total of 14 steroid preparations (9 nandrolone and 5 testosterone) were analysed. The identity of the steroid preparations were confirmed using gas chromatography mass spectrometry (GC-MS) and the δ13C values (a measure of the 13C/12C ratio) were determined using GC-C-IRMS.
RESULTS - Four nandrolone preparations displayed δ13C values that overlap with those considered endogenous (range -16 to -26 ‰). Two nandrolone and five testosterone preparations displayed δ13C values within the range -27 to -29 ‰, which while outside the typical endogenous range may be difficult to differentiate for endogenous values with the certainty required. The remaining preparations displayed δ13C values within the range expected for synthetic steroids (less than -29 ‰).
CONCLUSION - The findings of this study showed that steroid preparations available in the UK that have δ13C values within the endogenous range (and are potentially not detectable by GC-C-IRMS analysis), are both available and relatively prevalent.