Carbon isotope ratio (δ13C) values of urinary steroids for doping control in sport

Recent developments in the use of isotope ratio mass spectrometry in sports drug testing

“…In that year a research project focusing on the influence of diet on CIR of steroids was published [74] and another RefPop encompassing 171 male soccer players emerged [75]. Two laboratories reported data using collected samples, which were investigated for CIR and which gave a significant difference in δ values between athletes from different countries but which showed that the Δ values were not influenced [19,76]. Investigations on the misuse of 4-androstene-3,11,17-trione, a nutritional supplement [77], and a comprehensive method to detect cortisone misuse, again using oxidation of target analytes, were published [78].…”

“…In 2009, the influence of geographical variation on the CIR of steroids was reported by two groups [19,76]. Presumably, the reasons for these variations are due to the different eating habits together with the differing isotopic composition of food in various parts of the world [103].…”

Annual banned‐substance review: analytical approaches in human sports drug testing

“…In a comprehensive work, 1262 urine samples collected from athletes originating from 13 different countries and 5 continents were analyzed for their urinary androsterone and etiocholanolone δ 13 C and δ 13 C values (using pregnanediol and 11-keto-etiocholanolone as endogenous reference compounds) to serve as reference population for an improved interpretation of GC/C/IRMS data of doping control samples. [11] Significant differences in δ 13 C values were found to result from the athletes' origin (presumably due to the prevailing diet), thus supporting the requirement of an endogenous reference compound (ERC). The careful selection of an adequate ERC, however, and the determination of respective δ 13 C confidence limits were recommended.…”

Natural Hormones in Food-Producing Animals:Legal Measurements and Analytical Implications

“…This methodology has been applied successfully in urine to trace the administration of testosterone and estradiol esters in cattle (Buisson et al, 2005;Hebestreit et al, 2006). However, no thresholds of reference for these changes in the 13C/12C ratios of steroid hormones have been established yet, since their variations depend largely on the diet of the animal and also other factors such as age, sex or breed (Cawley et al, 2009;Ferchaud et al, 2000). In addition, GC-C-IRMS methods imply long and complicated steps of extraction and purification of the sample and also the use of semi-preparation HPLC and derivatization procedures (Buisson et al, 2005;Hebestreit et al, 2006).…”