Confirming testosterone administration by isotope ratio mass spectrometric analysis of urinary androstanediols

Anabolic steroids in livestock production: Background and implications for chemical food safety

The use of steroids in livestock animals is a source of concern for consumers because of the risks associated with the presence of their residues in foodstuffs of animal origin. Technological advances such as mass spectrometry have made it possible to play a fundamental role in controlling such practices, firstly for the discovery of marker metabolites but also for the monitoring of these compounds under the regulatory framework. Current control strategies rely on the monitoring of either the parent drug or its metabolites in various matrices of interest. As some of these steroids also have an endogenous status specific strategies have to be applied for control purposes. This review aims to provide a comprehensive and up-to-date knowledge of analytical strategies, whether targeted or non-targeted, and whether they focus on markers of exposure or effect in the specific context of chemical food safety regarding the use of anabolic steroids in livestock. The role of new approaches in data acquisition (e.g. ion mobility), processing and analysis, (e.g. molecular networking), is also discussed.

Investigations in carbon isotope ratios of seized testosterone and boldenone preparations

In order to detect the misuse of testosterone (T) or boldenone (Bo) in doping control analysis, the confirmation of atypical findings employing the determination of carbon isotope ratios (CIR) is mandatory for issuing adverse analytical findings. Elevated concentrations of T (or elevated T/epitestosterone ratios) may result from confounding factors such as ethanol intake, and the presence of low urinary concentrations of Bo can originate from endogenous or urinary in situ production of small amounts of the steroid. As pharmaceutical preparations of Bo and T are generally depleted in ¹³ C, their CIR differ significantly from the ¹³ C-enriched endogenous steroids. Some rare cases have been reported on pharmaceutical preparations showing ¹³ C-enriched isotope ratios that complicate the current application of CIR in sports drug testing. Therefore, the CIR of a subset of n = 157 T preparations and n = 39 Bo preparations seized in Switzerland and Germany between 2013 and 2018 was analyzed in order to estimate the possible impact of steroid preparations showing ¹³ C-enriched isotope ratios on the current approach to detect their misuse. All investigated Bo preparations showed CIR in the expected range between - 26.7 and -30.3‰. Within the T samples, 95% showed the expected values below -26‰ while six samples fall between -25 and -26‰ and one sample was indistinguishable from endogenously produced T with a CIR of -23.3‰.

Application of comprehensive 2D chromatography in the anti-doping field: Sample identification and quantification

Anti-doping analysis requires an exceptional level of accuracy and precision given the stakes that are at play. Current methods rely on the application of chromatographic techniques linked with mass spectrometry to provide this. However, despite the effectiveness of these techniques in achieving good selectivity and specificity, some issues still exist. In order to reach the minimum required performance level as set by WADA, labs commonly use selective monitoring by quadrupole mass spectrometry. This can be potentially fooled through the use of masking agents or by moving the peaks, as often only a small portion of the spectrum is used for analysis. Further issues exist in the inability to detect new or modified compounds, or to reanalyse samples/spectra. One technique that could overcome these problems is that of comprehensive 2D chromatography. Here a second separation column is employed to generate greater separative power. Compared to conventional separation, GCxGC allows for a greater peak capacity (i.e., number of peaks that can be resolved within a given time) and greater separation of coeluting compounds, which makes the technique promising for the complex task required in anti-doping. When combined with Time of Flight Mass Spectrometry this technique demonstrates vast potential allowing for full mass range datasets to be obtained for retroactive analysis. Similarly, LCxLC provides improvements in resolving power compared to its 1D counterpart and can be used both online as part of the analysis or offline solely as a purification step. In this review we summarise the work in this field so far, how comprehensive chromatography has been applied to anti-doping studies, and discuss the future application for this technique.

Isotope ratio mass spectrometry in antidoping analysis: The use of endogenous reference compounds

RATIONALE

Isotope ratio mass spectrometry (IRMS) is an analytical technique required by the World Antidoping Agency (WADA) before releasing of an adverse finding for the abuse of pseudoendogenous steroids (i.e. testosterone). For every single individual, the delta ¹³ C values (‰) of the selected target compounds (TCs, i.e. testosterone and/or its precursors/metabolites) are compared with those of endogenous reference compounds (ERCs). The aim of this work is to investigate the individual variation in the delta values of four different commonly used ERCs to establish the maximum acceptable variation, in order to detect potential outliers.

METHODS

Routine urine samples collected for antidoping purposes were submitted to IRMS confirmation. After a specific liquid chromatographic purification of the analytes of interest, the final extracts were analyzed by gas chromatography/combustion (GC/C)-IRMS. The selected ERCs monitored were pregnanediol, pregnanetriol, 11-keto-etiocholanolone and 11β-hydroxyandrosterone. The obtained ¹³ C delta values were statistically analyzed to evaluate their inter- and intra-individual distribution.

RESULTS

The delta values of the ERCs studied showed a normal distribution and no major differences among genders were observed. As expected, there are differences depending on the geographical origin of the samples, reflecting different dietary habits and food sources. The intra-individual dispersion, expressed as the standard deviation (SD) of the values of the studied ERCs, did not greatly exceed the instrumental error (0.5‰), demonstrating the good preservation of the delta values along the metabolic pathway.

CONCLUSIONS

For the selected ERCs of non-sporting volunteers and the urinary specimens from more than 1000 sportsmen, we can propose a maximum SD of 0.54‰ and range of 1.2‰ for delta ¹³ C values as acceptance criteria to detect potential outliers. These cases can be caused by the external masking effect of the administration of a substance modifying the delta values or outliers due to unforeseen procedural artifacts.

Intracrine androgen biosynthesis, metabolism and action revisited

Androgens play an important role in metabolic homeostasis and reproductive health in both men and women. Androgen signalling is dependent on androgen receptor activation, mostly by testosterone and 5α-dihydrotestosterone. However, the intracellular or intracrine activation of C₁₉ androgen precursors to active androgens in peripheral target tissues of androgen action is of equal importance. Intracrine androgen synthesis is often not reflected by circulating androgens but rather by androgen metabolites and conjugates. In this review we provide an overview of human C₁₉ steroid biosynthesis including the production of 11-oxygenated androgens, their transport in circulation and uptake into peripheral tissues. We conceptualise the mechanisms of intracrinology and review the intracrine pathways of activation and inactivation in selected human tissues. The contribution of liver and kidney as organs driving androgen inactivation and renal excretion are also highlighted. Finally, the importance of quantifying androgen metabolites and conjugates to assess intracrine androgen production is discussed.

Confounding factors and genetic polymorphism in the evaluation of individual steroid profiling

In the fight against doping, steroid profiling is a powerful tool to detect drug misuse with endogenous anabolic androgenic steroids. To establish sensitive and reliable models, the factors influencing profiling should be recognised. We performed an extensive literature review of the multiple factors that could influence the quantitative levels and ratios of endogenous steroids in urine matrix. For a comprehensive and scientific evaluation of the urinary steroid profile, it is necessary to define the target analytes as well as testosterone metabolism. The two main confounding factors, that is, endogenous and exogenous factors, are detailed to show the complex process of quantifying the steroid profile within WADA-accredited laboratories. Technical aspects are also discussed as they could have a significant impact on the steroid profile, and thus the steroid module of the athlete biological passport (ABP). The different factors impacting the major components of the steroid profile must be understood to ensure scientifically sound interpretation through the Bayesian model of the ABP. Not only should the statistical data be considered but also the experts in the field must be consulted for successful implementation of the steroidal module.

Carbon isotope ratios of nandrolone, boldenone, and testosterone preparations seized in Norway compared to those of endogenously produced steroids in a Nordic reference population

Determining the origin of anabolic androgenic steroids (AAS) that also are produced endogenously in the human body is a major issue in doping control. In some cases, the presence of nandrolone and boldenone metabolites might result from endogenous production. The GC-C-IRMS technique (gas chromatography-combustion-isotope ratio mass spectrometry) enables the carbon isotopic ratio (CIR) to be measured to determine the origin of these metabolites. The aim of this study was to use GC-C-IRMS to determine the δ(13) CVPDB values of seized boldenone and nandrolone preparations to decide if the steroids themselves were depleted in (13) C, compared to what is normally seen in endogenously produced steroids. In addition, several testosterone preparations were analyzed. A total of 69 seized preparations were analyzed. The nandrolone preparations showed δ(13) CVPDB values in the range of -31.5 ‰ to -26.7 ‰. The boldenone preparations showed δ(13) CVPDB values in the range of -32.0 ‰ to -27.8 ‰, and for comparison the testosterone preparations showed δ(13) CVPDB values of -31.0 ‰ to -24.2 ‰. The results showed that the values measured in the nandrolone and boldenone preparations were in the same range as those measured in the testosterone preparations. The study also included measurements of CIR of endogenously produced steroids in a Norwegian/Danish reference population. The δ(13) CVPDB values measured for the endogenous steroids in this population were in the range of -21.7 to -26.8. In general, most of the preparations investigated in this study show (13) C-depleted delta values compared to endogenously produced steroids reflecting a northern European diet.

A simplified and accurate method for the analysis of urinary metabolites of testosterone-related steroids using gas chromatography/combustion/isotope ratio mass spectrometry

RATIONALE

The analysis of urinary metabolites of testosterone-related steroids through the measurement of their carbon isotopic signature (δ(13) C) by gas chromatography/combustion/mass spectrometry (GC/C/IRMS) is a confirmation method employed in doping control analyses. Stringent analytical conditions are essential to an accurate and precise analysis as well as the proper selection of the metabolites, which forms the basis of the refined method presented in this paper.

METHODS

In a simplified approach, following enzymatic hydrolysis and extraction from a relatively low volume of urine sample, a one-step high-performance liquid chromatography (HPLC) purification was developed for seven diagnostic urinary metabolites (TS) including testosterone itself, dehydroepiandrosterone, 5α- and 5β-androstanediol, epitestosterone, androsterone, etiocholanolone and two endogenous reference compounds (ERC), 5β-pregnanediol and 5α-androst-16-en-3β-ol. These steroids were pooled in three fractions and analyzed as such. With regards to the GC/C/IRMS analysis, a multi-level isotopic calibration using the 'identical treatment' principle was created.

RESULTS

The proposed isotopic calibration yielded results for purified reference steroids with a precision ≤0.15 and accuracy of ≤0.30 ‰ (between-assay, n = 26). Compared to other common endogenous reference compounds, those selected in this study had δ(13) C values close to the target metabolites which, along with the proposed isotopic calibration, produced narrow reference intervals within ± 3‰ for most diagnostic TS-ERC pairs, in compliance with the requirements of the World Anti-Doping Agency.

CONCLUSIONS

These carefully controlled analytical conditions are compatible with routine operations, affording accurate and precise results for the more diagnostically relevant metabolites such as testosterone itself and the 5α- and 5β-androstanediols. The values of the TS-ERC pairs measured in reference populations are described and the results from the routine testing of several hundreds of athletes' samples are discussed. Robust, this technique permitted the detection of adverse findings that would have been missed had these low level metabolites not been analyzed.

Use of isotope ratio mass spectrometry to differentiate between endogenous steroids and synthetic homologues in cattle: a review

Although substantial technical advances have been achieved during the past decades to extend and facilitate the analysis of growth promoters in cattle, the detection of abuse of synthetic analogs of naturally occurring hormones has remained a challenging issue. When it became clear that the exogenous origin of steroid hormones could be traced based on the (13)C/(12)C isotope ratio of the substances, GC/C/IRMS has been successfully implemented to this aim since the end of the past century. However, due to the costly character of the instrumental setup, the susceptibility of the equipment to errors and the complex and time consuming sample preparation, this method is up until now only applied by a limited number of laboratories. In this review, the general principles as well as the practical application of GC/C/IRMS to differentiate between endogenous steroids and exogenously synthesized homologous compounds in cattle will be discussed in detail, and will be placed next to other existing and to be developed methods based on isotope ratio mass spectrometry. Finally, the link will be made with the field of sports doping, where GC/C/IRMS has been established within the World Anti-Doping Agency (WADA) approved methods as the official technique to differentiate between exogenous and endogenous steroids over the past few years.

Development of a GC/C/IRMS method--confirmation of a novel steroid profiling approach in doping control

In doping control, an athlete can only be convicted with the misuse with endogenous steroids like testosterone (T), if abnormal values of steroid metabolites and steroid ratios are observed and if the subsequent analysis with isotope ratios mass spectrometry (IRMS) confirms the presence of exogenously administered androgens. In this work, we compare the results of a novel steroid profiling approach with the performance an in-house developed IRMS method. The developed IRMS has the advantage over other methods to be relatively short in time and with target compounds androsterone, etiocholanolone, 5β-androstane 3α,17β-diol and 5α-androstane 3α,17β-diol. Pregnanediol was used as an endogenous reference compound (ERC). Reference limits for the IRMS values were established and applied as decision limits for the evaluation of excretion urine from administration with oral T, T-gel, dihydrotestosterone (DHT) - gel and dehydroepiandrosterone (DHEA). Results indicated the importance of both androstanediols as important IRMS markers where relative values compared to an ERC (Δδ(13)C) yielded better detection accuracy than absolute δ(13)C-values. The detection times of all administered endogenous steroids were evaluated using the proposed thresholds. The results of traditional steroid profiling and a new approach based upon minor steroid metabolites monitoring introduced in a longitudinal framework were evaluated with IRMS. With traditional steroid profiling methods, 95% of the atypical samples could be confirmed whereas an additional 74% of IRMS confirmed was provided by a new biomarkers strategy. These results prove that the other steroid profiling strategies can improve the efficiency in detection of misuse with endogenous steroids.

Influences of β-HCG administration on carbon isotope ratios of endogenous urinary steroids

Several factors influencing the carbon isotope ratios (CIR) of endogenous urinary steroids have been identified in recent years. One of these should be the metabolism of steroids inside the body involving numerous different enzymes. A detailed look at this metabolism taking into account differences found between steroids excreted as glucuronides or as sulphates and hydrogen isotope ratios of different steroids pointed out possibility of unequal CIR at the main production sites inside the male body - the testes and the adrenal glands. By administration of β-HCG it is possible to strongly stimulate the steroid production within the testes without influencing the production at the adrenal glands. Therefore, this treatment should result in changed CIR of urinary androgens in contrast to the undisturbed pre-treatment values. Four male volunteers received three injections of β-HCG over a time course of 5 days and collected their urine samples at defined intervals after the last administration. Those samples showing the largest response in contrast to the pre-administration urines were identified by steroid profile measurements and subsequent analysed by GC/C/IRMS. CIR of androsterone, etiocholanolone, testosterone, 5α- and 5β-androstanediol and pregnanediol were compared. While pregnanediol was not influenced, most of the investigated androgens showed depleted values after treatment. The majority of differences were found to be statistically significant and nearly all showed the expected trend towards more depleted δ(13)C-values. These results support the hypothesis of different CIR at different production sites inside the human body. The impact of these findings on doping control analysis will be discussed.

Determination of (13)C/(12)C ratios of endogenous urinary steroids excreted as sulpho conjugates

The application of a comprehensive gas chromatography/combustion/isotope ratio mass spectrometry-based method for the measurement of stable carbon isotopes of endogenous urinary steroids excreted as sulphates is presented. The key element in sample preparation is the consecutive cleanup with high-performance liquid chromatography of underivatized and acetylated steroids, which allows the isolation of seven analytes (pregn-5-ene-3β,17α,20α-triol, etiocholanolone, androsterone, epiandrosterone, dehydroepiandrosterone (DHEA), androst-5-ene-3β,17β-diol and androst-5-ene-3β,17α-diol) from a single urine specimen. These steroids are of particular importance to doping controls as they should enable the sensitive and retrospective detection of DHEA abuse by athletes.Depending on the biological background, the determination limit for all steroids ranges from 5 to 10 ng/mL for a 10 mL specimen. The method is validated by means of linear mixing models for each steroid, which covers the items, repeatability and reproducibility. The specificity was further demonstrated by gas chromatography/mass spectrometry for each analyte, and no influence of the sample preparation or the quantity of analyte on carbon isotope ratios was observed. In order to determine naturally occurring (13)C/(12)C ratios and urinary concentrations of all implemented steroids, a reference population of n = 67 subjects was measured to enable the calculation of reference limits for all relevant steroidal Δ values.The applicability of the developed method was tested by means of a DHEA excretion study. Despite the fact that orally ingested DHEA is preferentially converted into sulphated metabolites and that the renal clearance of sulphated steroids is slow, only the (13)C/(12)C ratio of EpiA demonstrated the potential to prolong the detection time for DHEA misuse.

Detection of the misuse of steroids in doping control

The list of prohibited substances of the World Anti-Doping Agency (WADA) classifies the administration of several steroids in sports as doping. Their analysis is generally performed using urine specimen as matrix. Lots of the steroids are extensively metabolised in the human body. Thus, knowledge of urinary excretion is extremely important for the sensitive detection of steroid misuse in doping control. The methods routinely used in steroid screening mainly focus on substances, that are excreted unconjugated or as glucuronides. Common procedures include deconjugation using a beta-glucuronidase enzyme. Following extraction and concentration the analytes are submitted to LC-MS(/MS) analysis and/or GC-MS(/MS) analyses. Besides the classical steroids, more and more products appear on the market for "dietary supplements" containing steroids that have never been marketed as approved drugs, mostly without proper labelling of the contents. To cover the whole range of potential products comprehensive screening tools have to be utilised in addition to the classical methods. Endogenous steroids, e.g. testosterone, represent a special group of compounds. As classical chemical methodology is incapable of discriminating synthetic hormones from the biosynthesised congeners, the method of steroid profiling is used for screening purpose. Additionally, based on isotope signatures a discrimination of synthetic and natural hormones can be achieved.

Screening for testosterone abuse in male athletes using the measurement of urinary LH, a revision of the paradigm

The primary screening method for the detection of doping by athletes using synthetic versions of endogenous steroids such as testosterone relies on measurement of the ratio of testosterone (T) to epitestosterone (E) in urine. In 2005 the World Anti-Doping Agency (WADA) lowered the T/E value at which samples undergo further investigation from six to four. This has resulted in a large increase in the number of athletes with naturally elevated T/E ratios undergoing investigation without a corresponding increase in the number of proven doping offences involving testosterone.Our objective was to develop a new simple screening protocol that can, with high probability, not only distinguish athletes whose natural T/E values exceed four from those whose T/E values have been elevated by testosterone doping but also detect those athletes with naturally low T/E values that do not exceed four despite being administered testosterone.Testosterone (250 mg Sustanon) was administered weekly to a group of 47 young adult males for five weeks in a double-blind placebo controlled study and urine samples collected. The samples were analysed for steroid concentrations using GC/MS and for luteinizing hormone (LH) by immunoassay.The elevation of T/E that occurred in all subjects was accompanied by a significant reduction in urinary LH concentrations to levels that are rare in normal subjects.The appropriate measurement of urinary LH, with the measurement of T/E values, can markedly improve the efficiency of detection of doping with testosterone by male athletes, particularly those who have low natural T/E ratios.

Androgen abuse in athletes: detection and consequences

CONTEXT

Doping with anabolic androgenic steroids (AAS) both in sports (especially power sports) and among specific subsets of the population is rampant. With increasing availability of designer androgens, significant efforts are needed by antidoping authorities to develop sensitive methods to detect their use.

EVIDENCE ACQUISITION

The PubMed and Google Scholar search engines were used to identify publications addressing various forms of doping, methods employed in their detection, and adverse effects associated with their use.

EVIDENCE SYNTHESIS

The list of drugs prohibited by the World Anti-Doping Agency (WADA) has grown in the last decade. The newer entries into this list include gonadotropins, estrogen antagonists, aromatase inhibitors, androgen precursors, and selective androgen receptor modulators. The use of mass spectrometry has revolutionized the detection of various compounds; however, challenges remain in identifying newer designer androgens because their chemical signature is unknown. Development of high throughput bioassays may be an answer to this problem. It appears that the use of AAS continues to be associated with premature mortality (especially cardiovascular) in addition to suppressed spermatogenesis, gynecomastia, and virilization.

CONCLUSION

The attention that androgen abuse has received lately should be used as an opportunity to educate both athletes and the general population regarding their adverse effects. The development of sensitive detection techniques may help discourage (at least to some extent) the abuse of these compounds. Investigations are needed to identify ways to hasten the recovery of the gonadal axis in AAS users and to determine the mechanism of cardiac damage by these compounds.

Nandrolone: a multi-faceted doping agent

Nandrolone or nortestosterone, an anabolic-androgenic steroid, has been prohibited by doping control regulations for more than 30 years. Although its main metabolism in the human body was already known at that time, and detection of its misuse by gas or liquid chromatographic separation with mass spectrometric detection is straightforward, many interesting aspects regarding this doping agent have appeared since.Over the years, nandrolone preparations have kept their position among the prohibited substances that are most frequently detected in WADA-accredited laboratories. Their forms of application range from injectable fatty acid esters to orally administered nandrolone prohormones. The long detection window for nandrolone ester preparations and the appearance of orally available nandrolone precursors have changed the pattern of misuse.At the same time, more refined analytical methods with lowered detection limits led to new insights into the pharmacology of nandrolone and revelation of its natural production in the body.Possible contamination of nutritional supplements with nandrolone precursors, interference of nandrolone metabolism by other drugs and rarely occurring critical changes during storage of urine samples have to be taken into consideration when interpreting an analytical finding.A set of strict identification criteria, including a threshold limit, is applied to judge correctly an analytical finding of nandrolone metabolites. The possible influence of interfering drugs, urine storage or natural production is taken into account by applying appropriate rules and regulations.

Detecting the administration of endogenous anabolic androgenic steroids

The detection of the administration of an androgen such as testosterone that could be present normally in human bodily fluids is based upon the methodical evaluation of key parameters of the urinary profile of steroids, precisely measured by GC/MS. Over the years, the markers of utilization were identified, the reference ranges of diagnostic metabolites and ratios were established in volunteers and in populations of athletes, and their stability in individual subjects was studied. The direct confirmation comes from the measurement of delta (13)C values reflecting their synthetic origin, ruling out a potential physiological anomaly. Several factors may alter the individual GC/MS steroid profile besides the administration of a testosterone-related steroid, the nonexhaustive list ranging from the microbial degradation of the specimen, the utilization of inhibitors of 5alpha-reductase or other anabolic steroids, masking agents such as probenecid, to inebriating alcohol drinking. The limitation of the testing strategy comes from the potentially elevated rate of false negatives, since only the values exceeding those of the reference populations are picked up by the GC/MS screening analyses performed by the laboratories on blind samples, excluding individual particularities and subtle doping. Since the ranges of normal values are often described from samples collected in Western countries, extrapolating data to all athletes appears inefficient. Furthermore, with short half-life and topical formulations, the alterations of the steroid profile are less pronounced and disappear rapidly. GC/C/IRMS analyses are too delicate and fastidious to be considered for screening routine samples. An approach based upon the individual athlete's steroid profiling is necessary to pick up variations that would trigger further IRMS analysis and investigations.

Stable isotope analysis of the bioelements: an introduction

The abundances of the stable isotopes of the bioelements are not constant. Subtle, but significant, variations may be induced by physical, physiological and biochemical processes. These variations may be detected and quantified. Often, isotope fingerprints are characteristic of certain processes and may reveal information concerning the sources and origins of compounds of interest. Moreover, natural variabilities of stable isotopes may be exploited in order to perform tracer experiments. The most accurate technology to perform stable isotope analysis is (gas) isotope ratio MS (IRMS). Compound-specific approaches employ hyphenation of GC and LC to IRMS. In these approaches, complete conversion to simple gases prior to MS is required. Analysis by stable isotope ratio spectroscopy currently approaches the accuracy of IRMS. However, for bioanalytical projects, it is still predominantly confined to material synthetically enriched with stable isotopes.

Drug testing data from the 2007 Pan American Games: delta13C values of urinary androsterone, etiocholanolone and androstanediols determined by GC/C/IRMS

The main purpose of this article is to show the application of the CG/C/IRMS in real time during competition in the steroid confirmation analysis. For this reason, this paper summarizes the results obtained from the doping control analysis during the period of the 2007 Pan American Games held in Rio de Janeiro, Brazil. Approximately 5600 athletes from 42 different countries competed in the games. Testing was performed in accordance to World Anti-Doping Agency (WADA) technical note for prohibited substances. This paper reports data where abnormal urinary steroid profiles, have been found with the screening procedures. One 8 mL urine sample was used for the analysis of five steroid metabolites with two separate analyses by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). Urine samples were submitted to GC/C/IRMS for confirmation analysis to determine the (13)C/(12)C ratio of selected steroids. Fifty-seven urine samples were analyzed by GC/C/IRMS and the delta(13)C values ( per thousand) of androsterone, etiocholanolone, 5beta-androstane-3alpha, 17beta-diol (5beta-diol), 5alpha-androstane-3alpha, 17beta-diol (5alpha-diol) and 5beta-pregnane-3alpha, 20alpha-diol (5beta-pdiol), the endogenous reference compound are presented. One urine sample with a testosterone/epitestosterone (T/E) ratio of 4.7 was confirmed to be positive of doping by GC/C/IRMS analysis. The delta values of 5beta-diol and 5alpha-diol were 3.8 and 10.8, respectively, compared to the endogenous reference compound 5beta-pdiol, which exceeded the WADA limit of 3 per thousand. The results obtained by CG/C/IRMS confirmation analyses, in suspicious samples, were conclusive in deciding whether or not a doping steroid violation had occurred.

Determination of the deuterium/hydrogen ratio of endogenous urinary steroids for doping control purposes

The development and application of a combined gas chromatography/thermal conversion/isotope ratio mass spectrometry (GC/TC/IRMS) method for D/H ratio determination of endogenous urinary steroids are presented. The key element in sample preparation was the consecutive cleanup with high-performance liquid chromatography of initially native and subsequently acetylated steroids. This strategy enabled sufficient cleanup off all target analytes for determination of their respective D/H values. Ten steroids (11beta-hydroxyandrosterone, 5alpha-androst-16-en-3alpha-ol, pregnanediol, androsterone, etiocholanolone, testosterone, epitestosterone, 5alpha-androstan-3alpha,17beta-diol, 5beta-androstan-3alpha,17beta-diol and dehydroepiandrosterone) were measured from a single urine specimen. Depending on the biological background, the determination limit for all steroids ranged from 10 to 15 ng/mL for a 20 mL specimen. The method was validated by application of linear mixing models on each steroid and covered repeatability and reproducibility. The specificity of the procedure was ensured by gas chromatography/mass spectrometry (GC/MS) analysis of the sample using equivalent chromatographic conditions to those employed in the GC/TC/IRMS measurement. Within the sample preparation, no isotopic fractionation was observed, and no amount-dependent shift of the D/H ratios during the measurement was noticed. Possible memory effects occurring during IRMS measurements were corrected by applying a simple rule of proportion. In order to determine the naturally occurring D/H ratios of all implemented steroids, a population of 18 male subjects was analyzed. Relevant mean Delta values among selected steroids were calculated which allowed us to study the metabolic pathways and production sites of all the implemented steroids with additional consideration of the corresponding (13)C/(12)C ratios.

Steroid isotopic standards for gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS)

Carbon isotope ratio (CIR) analysis of urinary steroids using gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS) is a recognized test to detect illicit doping with synthetic testosterone. There are currently no universally used steroid isotopic standards (SIS). We adapted a protocol to prepare isotopically uniform steroids for use as a calibrant in GCC-IRMS that can be analyzed under the same conditions as used for steroids extracted from urine. Two separate SIS containing a mixture of steroids were created and coded CU/USADA 33-1 and CU/USADA 34-1, containing acetates and native steroids, respectively. CU/USADA 33-1 contains 5alpha-androstan-3beta-ol acetate (5alpha-A-AC), 5alpha-androstan-3alpha-ol-17-one acetate (androsterone acetate, A-AC), 5beta-androstan-3alpha-ol-11, 17-dione acetate (11-ketoetiocholanolone acetate, 11k-AC) and 5alpha-cholestane (Cne). CU/USADA 34-1 contains 5beta-androstan-3alpha-ol-17-one (etiocholanolone, E), 5alpha-androstan-3alpha-ol-17-one (androsterone, A), and 5beta-pregnane-3alpha, 20alpha-diol (5betaP). Each mixture was prepared and dispensed into a set of about 100 ampoules using a protocol carefully designed to minimize isotopic fractionation and contamination. A natural gas reference material, NIST RM 8559, traceable to the international standard Vienna PeeDee Belemnite (VPDB) was used to calibrate the SIS. Absolute delta(13)C(VPDB) and Deltadelta(13)C(VPDB) values from randomly selected ampoules from both SIS indicate uniformity of steroid isotopic composition within measurement reproducibility, SD(delta(13)C)<0.2 per thousand. This procedure for creation of isotopic steroid mixtures results in consistent standards with isotope ratios traceable to the relevant international reference material.

Carbon isotope ratio (delta13C) values of urinary steroids for doping control in sport

The detection of steroids originating from synthetic precursors in relation to their chemically identical natural analogues has proven to be a significant challenge for doping control laboratories accredited by the World Anti-Doping Agency (WADA). Endogenous steroid abuse may be confirmed by utilising the atomic specificity of gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) that enables the precise measurement of differences in stable isotope ratios that arise as a result of fractionation patterns inherent in the source of steroids. A comprehensive carbon isotope ratio (delta(13)C) profiling study (n=1262) of urinary ketosteroids is reported that demonstrates the inter-individual variation that can be expected from factors such as diet, ethnicity, gender and age within and between different populations (13 countries). This delta(13)C distribution is shown by principal component analysis (PCA) to provide a statistical comparison to delta(13)C values observed following administration of testosterone enanthate. A limited collection of steroid diol data (n=100; consisting of three countries) is also presented with comparison to delta(13)C values of excreted testosterone to validate criteria for WADA accredited laboratories to prove doping offences.

Isotope ratio mass spectrometry analysis of the oxidation products of the main and minor metabolites of hydrocortisone and cortisone for antidoping controls

Metabolites of hydrocortisone (HC) and cortisone (C), namely tetrahydrocortisol (THF), tetrahydrocortisone (THE), allo-THF, allo-THE for the main metabolites and 11-hydroxyandrosterone, 11-hydoxyetiocholanolone, 11-ketoandrosterone, and 11-ketoetiocholanolone for the minor metabolites, as well as the two main metabolites of testosterone, androsterone and etiocholanolone, were separated from each other using HPLC fractionation of urine extracts. An isotopic ratio mass spectrometry (IRMS) analysis determined the absolute delta(13)C values of 5alpha-androstanetrione (5alpha-AT) and 5beta-androstanetrione (5beta-AT) as the oxidation products (ox-products) of the HC and C metabolites and as target compounds (TCs). We also performed IRMS analysis of 5alpha-androstanedione (5alpha-AD) and 5beta-androstanedione (5beta-AD) as the ox-products of etiocholanolone and androsterone and as endogenous reference compounds (ERCs). Urine samples came from two male volunteers treated with a single 10-mg oral dose and a single 100-mg intramuscular dose of HC hemisuccinate, a male volunteer treated with a single 25-mg oral dose of C acetate, and a control group of 30 drug-free athletes. The mean -3SD of delta(13)C depletion values from the controls were -1.46, -1.98, -1.78 and -2.42 for 5beta-AT-5beta-AD, 5alpha-AT-5beta-AD, 5beta-AT-5alpha-AD and 5alpha-AT-5alpha-AD, respectively, indicating -3 per thousand as a safe cut-off value for differentiating the pharmaceutical from the natural form. In the main metabolite fraction, delta(13)C depletion values peaked around -5 per thousand and -9 per thousand after oral and intramuscular administration of HC, respectively, and around -6 per thousand after oral administration of C. In comparison, less impressive results were obtained when IRMS analysis focused on the ox-products of the minor metabolites.

Steroid analysis and doping control 1960-1980: scientific developments and personal anecdotes

Definitive proof of anabolic steroid abuse in sports was not possible prior to the introduction of combined gas chromatography/mass spectrometry (GC/MS).This is a report of the early history (1960-1980) of GC/MS and radioimmunoassay, and how these techniques were utilized in the first years of steroid doping control in athletics. There were several key individuals and research groups involved in the early technical developments, and their essential contributions have been acknowledged. Our laboratory was the first IAAF (International Association of Athletic Federations) sanctioned site to do steroid GC/MS steroid analysis resulting in athletes being disqualified from competition. We had notable successes, including the only East German female competitor ever suspended during the tenure of the DDR (Deutsche Demokratische Republik). This paper not only covers scientific advances and milestones in the incorporation of steroid testing into international athletics, but also includes personal anecdotes of these early years before doping control became justifiably regimented. By the early 1980s, in anticipation of the Los Angeles Olympic games, dedicated year-round sports testing facilities had been established and part-time amateurs could step aside.