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de la Torre X, Jardines D, Curcio D, Colamonici C, Botrè F. Isotope ratio mass spectrometry in antidoping analysis: The use of endogenous reference compounds. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2019; 33:579-586. [PMID: 30589473 DOI: 10.1002/rcm.8377] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/13/2018] [Accepted: 12/19/2018] [Indexed: 06/09/2023]
Abstract
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.
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Affiliation(s)
- Xavier de la Torre
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197, Rome, Italy
| | - Daniel Jardines
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197, Rome, Italy
| | - Davide Curcio
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197, Rome, Italy
| | - Cristiana Colamonici
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197, Rome, Italy
| | - Francesco Botrè
- Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197, Rome, Italy
- Dipartimento di Medicina Sperimentale, "Sapienza" Università di Roma, Viale Regina Elena 324, 00161, Rome, Italy
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Impact of progesterone administration on doping test of endogenous steroids. Anal Bioanal Chem 2014; 406:6061-7. [DOI: 10.1007/s00216-014-8027-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 06/15/2014] [Accepted: 07/09/2014] [Indexed: 10/24/2022]
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Ouellet A, LeBerre N, Ayotte C. A simplified and accurate method for the analysis of urinary metabolites of testosterone-related steroids using gas chromatography/combustion/isotope ratio mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:1739-1750. [PMID: 23821567 DOI: 10.1002/rcm.6620] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Revised: 04/30/2013] [Accepted: 05/05/2013] [Indexed: 06/02/2023]
Abstract
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.
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Affiliation(s)
- Alexandre Ouellet
- Laboratoire de contrôle du dopage, INRS - Institut Armand-Frappier, Laval, Canada
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Yang S, Zhang D, Xu Y, Wang X, Liu X, Wang S, Wang J, Wu M, He Z, Zhao J, Yuan H. Discriminating the endogenous and exogenous urinary estrogens in human by isotopic ratio mass spectrometry and its potential clinical value. Steroids 2013; 78:297-303. [PMID: 23228444 DOI: 10.1016/j.steroids.2012.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 10/17/2012] [Accepted: 11/17/2012] [Indexed: 10/27/2022]
Abstract
Estrogens were prohibited in the food producing animals by European Union (96/22/EC directive) and added to the Report on Carcinogens in United States since 2002. Due to very low concentration in serum or urine (~pg/mL), the method of control its abuse had not been fully developed. The endogenous estrogens were separated from urines of 18 adult men and women. The exogenous estrogens were chemical reference standards and over the counter preparations. Two patients of dysfunctional uterine bleeding (DUB) administered exogenous estradiol and the urines were collected for 72 h. The urinary estrogens were separated by high-performance liquid chromatography (HPLC) and confirmed. The exogenous and exogenous estrogens were analyzed by gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) to determine the (13)C/(12)C ratio (δ(13)C‰). The δ(13)C‰ values of reference standard of E1, E2, and E3 were -29.36±0.72, -27.98±0.35, -27.62±0.51, respectively. The δ(13)C‰ values of the endogenous E1, E2, and E3 were -21.62±1.07, -22.14±0.98, and -21.88±1.16, with P<0.01 (t-test). Two DUB patients' urinary estradiol δ(13)C‰ values was depleted to -28.02±0.33 after the administration. The progesterone, 17α-hydroxyprogesterone, pregnanediol, as well as desogestrel and ethinylestradiol from contraceptives were also determined. Stable carbon isotope analysis can distinguish the endogenous and exogenous urinary estrogen in human.
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Affiliation(s)
- Sheng Yang
- National Laboratory of Anti-Doping, China Anti-Doping Agency, Beijing 100029, China.
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Ahrens BD, Butch AW. Carbon isotope ratio mass spectrometry for detection of endogenous steroid use: A testing strategy. Drug Test Anal 2013; 5:534-40. [DOI: 10.1002/dta.1447] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/20/2012] [Accepted: 11/21/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Brian D. Ahrens
- UCLA Olympic Analytical Laboratory, Department of Pathology & Laboratory Medicine, Geffen School of Medicine, Reagan UCLA Medical Center; Los Angeles; CA; USA
| | - Anthony W. Butch
- UCLA Olympic Analytical Laboratory, Department of Pathology & Laboratory Medicine, Geffen School of Medicine, Reagan UCLA Medical Center; Los Angeles; CA; USA
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A comprehensive procedure based on gas chromatography–isotope ratio mass spectrometry following high performance liquid chromatography purification for the analysis of underivatized testosterone and its analogues in human urine. Anal Chim Acta 2012. [DOI: 10.1016/j.aca.2012.10.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Piper T, Thomas A, Thevis M, Saugy M. Investigations on hydrogen isotope ratios of endogenous urinary steroids: reference-population-based thresholds and proof-of-concept. Drug Test Anal 2012; 4:717-27. [DOI: 10.1002/dta.1416] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 07/23/2012] [Accepted: 08/20/2012] [Indexed: 11/09/2022]
Affiliation(s)
- Thomas Piper
- Swiss Laboratory for Doping Analysis; University Center of Legal Medicine, Geneva and Lausanne, Centre Hospitalier Universitaire Vaudois and University Lausanne; Ch. des Croisettes 22; CH-1066; Epalinges; Switzerland
| | - Andreas Thomas
- German Sport University Cologne; Center for Preventive Doping Research; Am Sportpark Müngersdorf 6; 50933; Köln; Germany
| | - Mario Thevis
- German Sport University Cologne; Center for Preventive Doping Research; Am Sportpark Müngersdorf 6; 50933; Köln; Germany
| | - Martial Saugy
- Swiss Laboratory for Doping Analysis; University Center of Legal Medicine, Geneva and Lausanne, Centre Hospitalier Universitaire Vaudois and University Lausanne; Ch. des Croisettes 22; CH-1066; Epalinges; Switzerland
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Brooker L, Cawley A, Kazlauskas R, Goebel C, George A. Carbon isotope ratio analysis of endogenous glucocorticoid urinary metabolites after cortisone acetate and adrenosterone administration for doping control. Drug Test Anal 2012; 4:951-61. [DOI: 10.1002/dta.1403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Revised: 07/12/2012] [Accepted: 07/12/2012] [Indexed: 11/06/2022]
Affiliation(s)
| | - Adam Cawley
- Australian Sports Drug Testing Laboratory (ASDTL); National Measurement Institute; 105 Delhi Rd; North Ryde; NSW; 2113; Australia
| | - Ray Kazlauskas
- Australian Sports Drug Testing Laboratory (ASDTL); National Measurement Institute; 105 Delhi Rd; North Ryde; NSW; 2113; Australia
| | - Catrin Goebel
- Australian Sports Drug Testing Laboratory (ASDTL); National Measurement Institute; 105 Delhi Rd; North Ryde; NSW; 2113; Australia
| | - Adrian George
- School of Chemistry; Building F11, The University of Sydney; NSW; 2006; Australia
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Cawley AT, George AV. Complementary stable carbon isotope ratio and amount of substance measurements in sports anti-doping. Drug Test Anal 2012; 4:897-911. [DOI: 10.1002/dta.1378] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Revised: 05/06/2012] [Accepted: 05/08/2012] [Indexed: 11/11/2022]
Affiliation(s)
| | - Adrian V. George
- School of Chemistry; University of Sydney; Sydney; NSW; 2006; Australia
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Piper T, Schlug C, Mareck U, Schänzer W. Investigations on changes in 13C/12C ratios of endogenous urinary steroids after pregnenolone administration. Drug Test Anal 2011; 3:283-90. [DOI: 10.1002/dta.281] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 02/17/2011] [Accepted: 02/20/2011] [Indexed: 11/08/2022]
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Recent developments in the use of isotope ratio mass spectrometry in sports drug testing. Anal Bioanal Chem 2011; 401:433-47. [DOI: 10.1007/s00216-011-4886-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 03/03/2011] [Accepted: 03/08/2011] [Indexed: 10/18/2022]
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Brooker L, Parr MK, Cawley A, Flenker U, Howe C, Kazlauskas R, Schänzer W, George A. Development of criteria for the detection of adrenosterone administration by gas chromatography-mass spectrometry and gas chromatography-combustion-isotope ratio mass spectrometry for doping control. Drug Test Anal 2009; 1:587-95. [DOI: 10.1002/dta.108] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Aguilera R, Chapman TE, Pereira H, Oliveira GC, Illanes RP, Fernandes TF, Azevedo DA, Neto FA. Drug testing data from the 2007 Pan American Games: delta13C values of urinary androsterone, etiocholanolone and androstanediols determined by GC/C/IRMS. J Steroid Biochem Mol Biol 2009; 115:107-14. [PMID: 19428237 DOI: 10.1016/j.jsbmb.2009.03.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 03/12/2009] [Accepted: 03/31/2009] [Indexed: 11/17/2022]
Abstract
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.
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Affiliation(s)
- Rodrigo Aguilera
- House Ear Institute, 2100 West Third Street, Los Angeles, CA 90057, USA.
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Cawley AT, Trout GJ, Kazlauskas R, Howe CJ, George AV. Carbon isotope ratio (delta13C) values of urinary steroids for doping control in sport. Steroids 2009; 74:379-92. [PMID: 19056414 DOI: 10.1016/j.steroids.2008.11.004] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2008] [Revised: 10/19/2008] [Accepted: 11/05/2008] [Indexed: 10/21/2022]
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.
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Affiliation(s)
- Adam T Cawley
- Australian Sports Drug Testing Laboratory (ASDTL), National Measurement Institute (NMI), 1 Suakin Street, Pymble, NSW 2073, Australia
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Cawley AT, Flenker U. The application of carbon isotope ratio mass spectrometry to doping control. JOURNAL OF MASS SPECTROMETRY : JMS 2008; 43:854-864. [PMID: 18523972 DOI: 10.1002/jms.1437] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The administration of synthetic steroid copies is one of the most important issues facing sports. Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require methods of analysis that allow endogenous steroids to be distinguished from their synthetic analogs in urine. The ability to measure isotope distribution at natural abundance with high accuracy and precision has increased the application of Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS) to doping control in recent years. GC-C-IRMS is capable of measuring the carbon isotope ratio (delta(13)C) of urinary steroids and confirm their synthetic origin based on the abnormal (13)C content. This tutorial describes some of the complexities encountered by obtaining valid delta(13)C measurements from GC-C-IRMS and the need for careful interpretation of all relevant information concerning an individual's metabolism in order to make an informed decision with respect to a doping violation.
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Affiliation(s)
- Adam T Cawley
- Australian Sports Drug Testing Laboratory, National Measurement Institute, Pymble NSW 2073, Australia.
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Saudan C, Baume N, Emery C, Strahm E, Saugy M. Short term impact of Tribulus terrestris intake on doping control analysis of endogenous steroids. Forensic Sci Int 2008; 178:e7-10. [DOI: 10.1016/j.forsciint.2008.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 01/09/2008] [Accepted: 01/10/2008] [Indexed: 10/22/2022]
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Saudan C, Baume N, Robinson N, Avois L, Mangin P, Saugy M. Testosterone and doping control. Br J Sports Med 2006; 40 Suppl 1:i21-4. [PMID: 16799097 PMCID: PMC2657495 DOI: 10.1136/bjsm.2006.027482] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND OBJECTIVES Anabolic steroids are synthetic derivatives of testosterone, modified to enhance its anabolic actions (promotion of protein synthesis and muscle growth). They have numerous side effects, and are on the International Olympic Committee's list of banned substances. Gas chromatography-mass spectrometry allows identification and characterisation of steroids and their metabolites in the urine but may not distinguish between pharmaceutical and natural testosterone. Indirect methods to detect doping include determination of the testosterone/epitestosterone glucuronide ratio with suitable cut-off values. Direct evidence may be obtained with a method based on the determination of the carbon isotope ratio of the urinary steroids. This paper aims to give an overview of the use of anabolic-androgenic steroids in sport and methods used in anti-doping laboratories for their detection in urine, with special emphasis on doping with testosterone. METHODS Review of the recent literature of anabolic steroid testing, athletic use, and adverse effects of anabolic-androgenic steroids. RESULTS Procedures used for detection of doping with endogenous steroids are outlined. The World Anti-Doping Agency provided a guide in August 2004 to ensure that laboratories can report, in a uniform way, the presence of abnormal profiles of urinary steroids resulting from the administration of testosterone or its precursors, androstenediol, androstenedione, dehydroepiandrosterone or a testosterone metabolite, dihydrotestosterone, or a masking agent, epitestosterone. CONCLUSIONS Technology developed for detection of testosterone in urine samples appears suitable when the substance has been administered intramuscularly. Oral administration leads to rapid pharmacokinetics, so urine samples need to be collected in the initial hours after intake. Thus there is a need to find specific biomarkers in urine or plasma to enable detection of long term oral administration of testosterone.
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Affiliation(s)
- C Saudan
- Swiss Laboratory for Doping Analyses, Institute of Legal Medicine, Lausanne, Switzerland.
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Abstract
This article reviews the progress in the chemistry of the steroids that was published between January and December 2005. The reactions and partial synthesis of estrogens, androgens, pregnanes, bile acid derivatives, cholestanes and vitamin D analogues are covered. There are 139 references.
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Affiliation(s)
- James R Hanson
- Department of Chemistry, University of Sussex, Brighton, Sussex BN1 9QJ, UK
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