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1.
Forensic Sci Int ; 208(1-3): 129-38, 2011 May 20.
Article in English | MEDLINE | ID: mdl-21177052

ABSTRACT

Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require criteria that allow endogenous steroids to be distinguished from their synthetic analogues in urine. Methodology based on "looking outside the metabolic box" was used in this study to identify diagnostic urinary markers of 4-androstenediol (4-ADIOL) administration. Androst-2,4-diene-17-one and androst-3,5-diene-17-one are proposed to be formed in urine from acid-catalyzed hydrolysis of 4-ADIOL sulfoconjugate, a major phase II metabolic product of 4-ADIOL. The presence of these markers in the routine gas chromatography-mass spectrometry (GC-MS) steroid screen was suitable to identify samples requiring confirmation by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) - to measure the carbon isotope ratio (δ(13)C) of the androstdiene markers and confirm their likely synthetic origin based on depleted (13)C content.


Subject(s)
Anabolic Agents/administration & dosage , Androstanes/urine , Androstenediol/administration & dosage , Doping in Sports , Substance Abuse Detection/methods , Androstanes/chemistry , Biomarkers/urine , Carbon Isotopes/analysis , Gas Chromatography-Mass Spectrometry , Humans , Molecular Structure
2.
Steroids ; 74(3): 379-92, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19056414

ABSTRACT

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.


Subject(s)
Carbon Isotopes/analysis , Doping in Sports , Steroids/urine , Gas Chromatography-Mass Spectrometry/methods , Humans , Substance Abuse Detection/methods
3.
Drug Test Anal ; 1(11-12): 511-7, 2009 Nov.
Article in English | MEDLINE | ID: mdl-20355166

ABSTRACT

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.


Subject(s)
Doping in Sports , Luteinizing Hormone/urine , Substance Abuse Detection/methods , Testosterone/urine , Adult , Athletes , Double-Blind Method , Epitestosterone/urine , Growth Hormone/administration & dosage , Humans , Injections, Intramuscular , Injections, Subcutaneous , Male , Placebos , Testosterone/administration & dosage
4.
Rapid Commun Mass Spectrom ; 22(24): 4147-57, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19025884

ABSTRACT

Studies have shown that the administration of androstenedione (ADIONE) significantly increases the urinary ratio of testosterone glucuronide to epitestosterone glucuronide (T/E) - measured by gas chromatography/mass spectrometry (GC/MS) - in subjects with a normal ( approximately 1) or naturally high (>1) initial values. However, the urinary T/E ratio has been shown not to increase in subjects with naturally low (<1) initial values. Such cases then rely on the detection of C(6)-hydroxylated metabolites shown to be indicative of ADIONE administration. While these markers may be measured in the routine GC/MS steroid profile, their relatively low urinary excretion limits the use of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to specifically confirm ADIONE administration based on depleted (13)C content. A mass spectrometry strategy was used in this study to identify metabolites of ADIONE with the potential to provide compound-specific detection. C(4)-hydroxylation was subsequently shown to be a major metabolic pathway following ADIONE administration, thereby resulting in urinary excretion of 4-hydroxyandrostenedione (4OH-ADIONE). Complementary analysis of 4OH-ADIONE by GC/MS and GC/C/IRMS was used to confirm ADIONE administration.


Subject(s)
Androstenedione/analogs & derivatives , Androstenedione/urine , Doping in Sports , Spectrometry, Mass, Electrospray Ionization/methods , Substance Abuse Detection/methods , Adult , Chromatography, Gas/methods , Chromatography, High Pressure Liquid , Humans , Male , Mass Screening/methods , Reproducibility of Results , Spectrophotometry, Infrared , Young Adult
5.
Article in English | MEDLINE | ID: mdl-16154518

ABSTRACT

The need for laboratories accredited by the World Anti-Doping Agency (WADA) to develop methods of analysis for steroids excreted primarily as their sulfate conjugates has faced significant analytical challenges. One of the issues relates to the extraction of these metabolites from urine in a relatively pure state. The use of (-)-N,N-dimethylephedrinium bromide as an ion pairing reagent was optimised to produce a method that is selective for the extraction of steroid sulfates prior to GC-MS or LC-MS analysis, with minimal contributions from the urine matrix. The recovery of androsterone from its sulfate conjugate was determined to be 67% with a relative quantitative uncertainty of +/-14% (k = 2).


Subject(s)
Anabolic Agents/urine , Substance Abuse Detection/methods , Sulfates/urine , Chromatography, Liquid , Doping in Sports , Gas Chromatography-Mass Spectrometry , Humans , Reference Standards , Reproducibility of Results , Sensitivity and Specificity
6.
J Chromatogr Sci ; 43(1): 32-8, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15808004

ABSTRACT

The use of gas chromatography (GC)-combustion (C)-isotope ratio mass spectrometry (IRMS) demonstrates that a single oral administration of dehydroepiandrosterone (DHEA, 100 mg) to a male subject significantly lowers the 13C content of etiocholanolone (Et) and androsterone (A) in the subject's urine. The difference in carbon isotope ratio (d13C per thousand) values between Et and A increases from 1.6 per thousand at the time of administration to 5.1 per thousand at 26 h post-administration, indicating preferential metabolism of administered DHEA to form Et in relation to A. Multiple oral administrations of DHEA to a male subject reveals lower d13C values during the excretion period of Et (-31.7 per thousand to -34.6 per thousand) and A (-31.4 per thousand to -33.0 per thousand) to that of the d13C value of the administered DHEA (-31.3 per thousand). Reference distributions of d13C Et and d13C A constructed from normal athlete populations within Australia and New Zealand show a small natural discrimination against 13C in the formation of Et relative to A (mean=0.3 per thousand, n=167, p=0.007). Amplified differences between d13C Et and d13C A, and in vivo 13C depletion measured by GC-C-IRMS are shown to be potentially useful for doping control.


Subject(s)
Anabolic Agents/isolation & purification , Androgens/isolation & purification , Chemical Fractionation/methods , Doping in Sports/prevention & control , Adult , Androsterone/urine , Australia , Carbon Isotopes/urine , Dehydroepiandrosterone/administration & dosage , Dehydroepiandrosterone/pharmacokinetics , Etiocholanolone/urine , Gas Chromatography-Mass Spectrometry/methods , Humans , Male , New Zealand , Sports
7.
Chem Soc Rev ; 33(1): 1-13, 2004 Jan 10.
Article in English | MEDLINE | ID: mdl-14737504

ABSTRACT

Sport plays a major role in the lives of many people, both for active participation and as entertainment. Sport is now a huge nationally and internationally based industry. The desire to win has led some athletes to resort to the use of performance enhancing drugs. With huge financial rewards now available in some sports the pressure to excel has grown. Some have argued that drug use should be given free rein, however most people are of the view that it is athletic prowess that should be applauded not the efficacy of various performance enhancing drugs. Apart from the obvious aspects of equality and fair play, the use of drugs is associated with significant health risks. In the 1960's the use of stimulants in sports such as cycling led to the death of at least one cyclist. Since 1968 the International Olympic Committee (IOC) has required all Olympic Games' host cities to provide laboratory facilities for the analysis and detection of performance enhancing drugs. There are now 29 IOC accredited laboratories throughout the world that routinely test samples from athletes for the presence of such drugs. The purpose of this tutorial review is to give an overview of drug testing procedures, including those that were used at the last summer Olympic Games in Sydney 2000, and the incorporation of the latest developments in analytical chemistry technology in the drug testing process. More recently, developments in biotechnology mean that the use of whole new classes of drugs are banned in sport, often requiring new methodologies and techniques for their analysis. The contest between those who wish to cheat and those who wish to maintain fair play in sport is an ongoing one.


Subject(s)
Doping in Sports/prevention & control , Substance Abuse Detection/methods , Anabolic Agents/urine , Central Nervous System Stimulants/urine , Diuretics/urine , Doping in Sports/classification , Doping in Sports/trends , Hormones/urine , Humans , Molecular Structure , Narcotics/urine , Steroids/urine , Substance Abuse Detection/trends , Time Factors
8.
Haematologica ; 88(3): 333-44, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12651273

ABSTRACT

BACKGROUND AND OBJECTIVES: We previously developed blood tests that were introduced at the Sydney 2000 Olympic Games to identify athletes injecting recombinant human erythropoietin (rHuEPO). The aim of this study was to re-analyse our existing database to develop models with heightened sensitivity, using wherever possible blood parameters measurable with appropriate standards of analytical performance. DESIGN AND METHODS: The principal database for this study was derived from a double-blind trial in which 57 recreational athletes were administered either rHuEPO or placebo. Standard discriminant analysis was used to derive two ON models (ON-hes and ON-he) and two OFF models (OFF-hr and OFF-hre) sensitive to accelerated and decelerated erythropoiesis respectively, utilising concentrations of hemoglobin (h), erythropoietin (e) and serum transferrin receptor (s), as well as percent reticulocytes (r). The ability of our models to detect rHuEPO administration was assessed by comparing model scores of subjects in the administration trial with the model scores of 1152 elite athletes from 12 countries. RESULTS: The ability of the new models to detect rHuEPO administration was generally higher than that of our previous models, particularly during phases when low doses of rHuEPO were used, and after injections had ceased. INTERPRETATION AND CONCLUSIONS. The increased stability of the new blood parameters facilitates transport of samples to central laboratories, and the heightened sensitivity of the new models makes them better than existing models for federations wishing to screen samples for urine testing and to identify and target suspect athletes for out-of-competition testing. However procedures should be incorporated that respect an elevated model score caused by genetic, health or environmental circumstances.


Subject(s)
Doping in Sports/prevention & control , Erythropoietin/blood , Substance Abuse Detection/methods , Double-Blind Method , Female , Hemoglobins/analysis , Humans , Male , Models, Statistical , Receptors, Transferrin/blood , Recombinant Proteins , Reticulocyte Count , Sensitivity and Specificity
9.
Haematologica ; 87(12): 1248-57, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12495898

ABSTRACT

BACKGROUND AND OBJECTIVES: Our previous research developed two statistical models that are useful indicators of current (ON-model) or recently discontinued (OFF-model) recombinant human erythropoietin (rHuEPO) use by athletes. The component variables of the ON-model are hematocrit (Hct), reticulocyte hematocrit (RetHct), serum erythropoietin (EPO), percent macrocytes (%Macro), and soluble transferrin receptor (sTfr), whilst the OFF-model uses only the first three variables. Genetics and training modalities of elite athletes may conceivably produce unusual values for blood parameters related to erythropoiesis. The aims of this study were to develop reference ranges in elite athletes for key hematologic parameters as well as ON- and OFF-models scores, and to evaluate the effect of ethnicity, gender, residence at moderate altitude (approximately 2000 m) and within-individual variation on the variables and model scores. DESIGN AND METHODS: Over a period of three weeks, 413 female and 739 male elite athletes from 12 countries visited laboratories to provide three blood samples for analysis of blood parameters sensitive to erythropoiesis. For each parameter and for the ON- and OFF-model scores, we used mixed modeling to establish the range within which we could be 95% certain that the value for a randomly chosen athlete would fall, taking into account various random effects (variation within and between subjects and laboratories) and fixed effects (means for different levels of ethnicity, age, sport, altitude of residency). We performed similar analyses for changes in the ON- and OFF-model scores between the three visits. RESULTS: Most fixed effects were accompanied by clear-cut, small to moderate differences in several parameters. However, residency at moderate altitude was accompanied by a much higher hematocrit than residency nearer sea level, with the mean (and 95% confidence limits) for the difference being 2.3 (0.9 to 3.7) and 1.8 (0.1 to 3.5) units for males and females, respectively. Males at altitude also demonstrated a moderately higher ON-model score. Otherwise the influence of these effects was small for ON-, OFF- and changes in model scores. INTERPRETATION AND CONCLUSIONS: Assessment of an athlete's blood parameters and ON- and OFF-model scores may need adjustment for training modalities and other characteristics of the subject. Changes in model scores (together with monitoring of urine samples for the presence of rHuEPO) provide a promising approach to detection of rHuEPO abuse, because they are less sensitive to subject characteristics and less variable than raw model scores.


Subject(s)
Doping in Sports/statistics & numerical data , Erythropoiesis/drug effects , Erythropoietin/standards , Adolescent , Adult , Altitude , Biomarkers/blood , Erythropoietin/administration & dosage , Erythropoietin/pharmacology , Ethnicity , Female , Humans , Male , Recombinant Proteins , Reference Values , Sex Factors
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