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1.
Drug Test Anal ; 15(1): 27-41, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35633098

RESUMO

Consumption of hemp products is continuously growing, with an expanding scope of applications. Suppliers operate through different distribution channels, but the Internet is a major retail platform. Hemp products are prepared from cannabis plants and, therefore, might contain a variety of different natural cannabinoids. According to the regulations of the World Anti-Doping Agency, all natural and synthetic cannabinoids are prohibited in-competition, with the explicit exemption of cannabidiol. Therefore, an investigation of 23 hemp products for the presence of cannabinoids was performed to determine the likelihood of unintentional violations of anti-doping regulations. An assay for the detection of 16 cannabinoids in nutritional supplements was developed and validated. The sample preparation consisted of QuEChERS extraction, trimethylsilylation, and analysis by gas chromatography/tandem mass spectrometry. All 23 commercially available hemp products were analyzed, and assay characteristics such as selectivity, limit of detection, limit of identification, limit of quantification, linearity, imprecision, recovery, and accuracy were determined. Twenty of 23 hemp products included a variety of cannabinoids at, occasionally, substantial concentrations, with four products covering the entire spectrum of tested cannabinoids. An ethics committee-approved single-dose administration study was conducted with the commercially available hemp products, investigating the presence of 16 cannabinoids in urine collected pre- and post-consumption. Variable patterns of cannabinoids or their metabolites in urine were observed. In 30% of the urine samples collected 8 h after ingestion, the presence of a prohibited cannabinoid would have resulted in an unintentional violation of anti-doping regulations.


Assuntos
Canabidiol , Canabinoides , Cannabis , Cannabis/química , Cromatografia Gasosa-Espectrometria de Massas , Canabinoides/análise , Canabidiol/análise , Bioensaio
3.
Drug Test Anal ; 13(3): 539-549, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33125823

RESUMO

According to the World Anti-Doping Agency (WADA) regulations, cannabinoids use is prohibited in competition except for cannabidiol (CBD) use. For an adverse analytical finding (AAF) in doping control, cannabinoid misuse is based on identification of the pharmacologically inactive metabolite 11-nor-delta-9-carboxy-tetrahydrocannabinol-9-carboxylic acid (carboxy-THC) in urine at a concentration greater than 180 ng/ml. All other (minor) cannabinoids are reported as AAF when identified, except for CBD that has been explicitly excluded from the class of cannabinoids on WADA's Prohibited List since 2018. However, due to the fact that CBD isolated from cannabis plants may contain additional minor cannabinoids, the permissible use of CBD can lead to unintentional violations of antidoping regulations. An assay for the detection of 16 cannabinoids in human urine was established. The sample preparation consisted of enzymatic hydrolysis of glucuronide conjugates, liquid-liquid extraction, trimethylsilylation, and analysis by gas chromatography/tandem mass spectrometry (GC-MS/MS). Spot urine samples from CBD users, as well as specimens obtained from CBD administration studies conducted with 15 commercially available CBD products, were analyzed, and assay characteristics such as selectivity, reproducibility of detection at the minimum required performance level, limit of detection, and limit of identification were determined. An ethical committee approved controlled single dose commercially available CBD products administration study was conducted to identify 16 cannabinoids in urine samples collected after ingestion or application of the CBD products as well as their presence in spot urine samples of habitual CBD users. Variable patterns of cannabinoids or their metabolites were observed in the urine samples, especially when full spectrum CBD products were consumed. The presence of minor cannabinoids or their metabolites in an athlete's in-competition urine sample represents a substantial risk of an antidoping rule violation.


Assuntos
Canabidiol/análise , Canabinoides/análise , Dopagem Esportivo/prevenção & controle , Detecção do Abuso de Substâncias/métodos , Adulto , Idoso , Canabidiol/urina , Canabinoides/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Extração Líquido-Líquido , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
4.
Foods ; 9(8)2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32727139

RESUMO

A narrative review with an overall aim of indicating the current state of knowledge and the relevance concerning food and supplement contamination and/or adulteration with doping agents and the respective implications for sports drug testing is presented. The identification of a doping agent (or its metabolite) in sports drug testing samples constitutes a violation of the anti-doping rules defined by the World Anti-Doping Agency. Reasons for such Adverse Analytical Findings (AAFs) include the intentional misuse of performance-enhancing/banned drugs; however, also the scenario of inadvertent administrations of doping agents was proven in the past, caused by, amongst others, the ingestion of contaminated dietary supplements, drugs, or food. Even though controversial positions concerning the effectiveness of dietary supplements in healthy subjects exist, they are frequently used by athletes, anticipating positive effects on health, recovery, and performance. However, most supplement users are unaware of the fact that the administration of such products can be associated with unforeseeable health risks and AAFs in sports. In particular anabolic androgenic steroids (AAS) and stimulants have been frequently found as undeclared ingredients of dietary supplements, either as a result of cross-contaminations due to substandard manufacturing practices and missing quality controls or an intentional admixture to increase the effectiveness of the preparations. Cross-contaminations were also found to affect therapeutic drug preparations. While the sensitivity of assays employed to test pharmaceuticals for impurities is in accordance with good manufacturing practice guidelines allowing to exclude any physiological effects, minute trace amounts of contaminating compounds can still result in positive doping tests. In addition, food was found to be a potential source of unintentional doping, the most prominent example being meat tainted with the anabolic agent clenbuterol. The athletes' compliance with anti-doping rules is frequently tested by routine doping controls. Different measures including offers of topical information and education of the athletes as well as the maintenance of databases summarizing low- or high-risk supplements are important cornerstones in preventing unintentional anti-doping rule violations. Further, the collection of additional analytical data has been shown to allow for supporting result management processes.

5.
Drug Test Anal ; 3(11-12): 820-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22081503

RESUMO

The determination of salbutamol and its glucuronide in human urine following the inhalative and oral administration of therapeutic doses of salbutamol preparations was performed by means of direct urine injection utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS) and employing d(3)-salbutamol and d(3)-salbutamol glucuronide as internal standards. Unconjugated salbutamol was detected in all administration study urine samples. Salbutamol concentrations following inhalation were commonly (99%) below 1000 ng/ml whereas values after oral administration frequently (48%) exceeded this threshold. While salbutamol glucuronide was not detected in urine samples collected after inhalation of the drug, 26 out of 82 specimens obtained after oral application contained salbutamol glucuronide with a peak value of 63 ng/ml. The percentage of salbutamol glucuronide compared to unconjugated salbutamol was less than 3%. Authentic doping control urine samples indicating screening results for salbutamol less than 1000 ng/ml, showed salbutamol glucuronide concentrations between 2 and 6 ng/ml, whereas adverse analytical findings resulting from salbutamol levels higher than 1000 ng/ml, had salbutamol glucuronide values between 8 and 15 ng/ml. The approach enabled the rapid determination of salbutamol and its glucuronic acid conjugate in human urine and represents an alternative to existing procedures since time-consuming hydrolysis or derivatization steps were omitted. Moreover, the excretion of salbutamol glucuronide in human urine following the administration of salbutamol was proven.


Assuntos
Albuterol/urina , Broncodilatadores/urina , Dopagem Esportivo , Glucuronídeos/urina , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Administração por Inalação , Administração Oral , Albuterol/administração & dosagem , Broncodilatadores/administração & dosagem , Cromatografia Líquida/métodos , Glucuronídeos/administração & dosagem , Humanos , Limite de Detecção , Masculino
6.
Drug Test Anal ; 3(5): 283-90, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21538944

RESUMO

For the detection of possible misuse of naturally occurring anabolic androgenic steroids like testosterone (T), anti-doping laboratories use a combination of two techniques. One is molecular steroid profiling to evaluate urinary steroid concentrations and normal diagnostic ratios. The other is isotope ratio mass spectrometry (IRMS), in which the ¹³C/¹²C ratios of target analytes like T are compared to the ¹³C/¹²C ratios of endogenous reference compounds (ERCs). The ¹³C/¹²C of the most commonly used ERC, pregnanediol (5ß-pregnane-3α,20α-diol, PD), can be influenced by administration of pregnenolone (3ß-hydroxy-pregn-5-en-20-one, PREG). Therefore PREG administration bears the potential to circumvent IRMS testing for doping control samples. In order to investigate the influence of PREG on PD and on other urinary excreted steroids, administration studies with oral and transdermal application of PREG were carried out. The influence of PREG administration on concentrations and ¹³C/¹²C ratios of all investigated target analytes was negligible. Only PD and 5ß-pregnan-3α-ol-20-one (3aP) showed significant depletion in both their glucuronidated and sulfated steroids. The results suggest that appropriate alternative ERCs are: 11ß-hydroxy-androsterone/etiocholanolone, 5ß-pregnane-3α,17,20α-triol, pregn-5-ene-3ß,17,20α-triol and cholesterol. Due to its properties to disguise the misuse of anabolic steroids by influencing the ¹³C/¹²C ratio of PD, PREG should be considered to be added to the World Anti-Doping Agency (WADA) list of prohibited substances as a masking agent.


Assuntos
Dopagem Esportivo , Pregnanodiol/urina , Pregnenolona/urina , Detecção do Abuso de Substâncias/métodos , Administração Cutânea , Administração Oral , Adulto , Anabolizantes/urina , Isótopos de Carbono/química , Glucuronídeos/urina , Humanos , Masculino , Espectrometria de Massas/métodos , Pregnenolona/administração & dosagem , Pregnenolona/metabolismo , Padrões de Referência , Sulfatos/urina , Testosterona/urina
7.
Drug Test Anal ; 2(11-12): 637-42, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21204295

RESUMO

The testosterone/epitestosterone (T/E) ratio was implemented as an indirect parameter for the detection of testosterone administration with an empirically established threshold value at T/E = 6. In 2005, the T/E reporting threshold was lowered from six to four. Between 2005 and 2009, 63 510 doping control urine samples were analyzed in the Cologne laboratory. A total of 1442 specimens (2.3%) showed a T/E > 4; 80 (5.5%) of which were tested positive by means of isotope ratio mass spectrometry (IRMS); and most of which (68) originated from strength sport disciplines. Specimens of high T/E ratio showed a much higher probability for being confirmed to contain exogenous testosterone using IRMS analysis than samples of low T/E values. Considering the small number of adverse analytical findings triggered by lowering the T/E reporting threshold (978 urine specimens with T/E ratios between 4 and 6 yielded only 4 (0.4%) positive IRMS findings) and the known limitations of the T/E ratio as discriminating parameter (UGT2B17 polymorphism), the currently mandatory approach shows only marginal overall efficiency. A more effective tool for the detection of the misuse of testosterone would be the implementation of individual reference ranges. Until athlete steroidal passports are available, it is suggested to exceed the threshold level for T/E from 4 to 6 and perform obligatory IRMS analysis for specimens showing T/E > 6. Further conditions triggering IRMS analysis could be suppressed luteinizing hormone (LH) values in males and disproportionate changes of relevant parameters in individual profiles evidently not resulting from ethanol consumption.


Assuntos
Dopagem Esportivo , Epitestosterona/urina , Detecção do Abuso de Substâncias/tendências , Testosterona/urina , Feminino , Humanos , Masculino , Detecção do Abuso de Substâncias/métodos
8.
Drug Test Anal ; 1(11-12): 505-10, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20355165

RESUMO

According to the regulations of the World Anti-Doping Agency (WADA), the use of cannabinoids is forbidden in competition. In doping controls, the detection of cannabinoid misuse is based on the analysis of the non-psychoactive metabolite 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (carboxy-THC). The determination of values greater than 15 ng/mL in urine represents an adverse analytical finding; however, no accurate prediction of the time of application is possible as the half-life of carboxy-THC ranges between three and four days. Consequently the detection of carboxy-THC in doping control urine samples collected in competition might also result from cannabis use in out-of-competition periods. The analysis of the glucuronide of the pharmacologically active delta 9-tetrahydrocannabinol (THC-gluc) may represent a complementary indicator for the detection of cannabis misuse in competition.An assay for the determination of THC-gluc in human urine was established. The sample preparation consisted of liquid-liquid extraction of urine specimens, and extracts were analysed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Authentic doping-control urine samples as well as specimens obtained from a controlled smoking study were analysed and assay characteristics such as specificity, detection limit (0.1 ng/mL), precision (>90%), recovery ( approximately 80%), and extraction efficiency (90%) were determined.


Assuntos
Dopagem Esportivo , Dronabinol/análogos & derivados , Dronabinol/farmacocinética , Glucuronídeos/urina , Fumar Maconha/urina , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida/métodos , Dronabinol/urina , Humanos , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo
9.
Drug Test Anal ; 1(11-12): 576-86, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20355174

RESUMO

Epitestosterone (17alpha-hydroxy-androst-4-en-3-one, EpiT) belongs to the list of prohibited substances of the World Anti-Doping Agency (WADA). Although it possesses no anabolic effect, it is presumed to be misused by athletes in order to mask administration of testosterone (T) by lowering the urinary T/EpiT ratio.To improve detection, an excretion study with 40 mg of orally administered EpiT was conducted focusing on the metabolites of EpiT: 5alpha- and 5beta-androstane-3alpha,17 alpha-diol (5aEpiD and 5bEpiD). A reference population of n = 74 volunteers was investigated to elucidate the urinary concentrations of these steroids.In order to prove whether an unusual finding in urinary concentrations or ratios is due to an illicit intake of steroids or due to physiological elevation, determination of carbon isotope ratios is advisable. A method for isotope ratio determination was developed to enable (13)C/(12)C ratios of EpiT, 5bEpiD, 5aEpiD, pregnanediol and androsterone and etiocholanolone to be measured from a single urine specimen. The method's validity was tested by applying linear mixing models and specificity was ensured by means of gas chromatography/mass spectrometry analysis. delta(13)C values at natural levels were determined with a reference population and both Delta values and corresponding reference limits were calculated.Considering the implemented EpiT-metabolites, a more than twofold extension of the detection time of EpiT administration was achieved with both the urinary concentration thresholds and the (13)C/(12)C ratios.


Assuntos
Isótopos de Carbono/urina , Epitestosterona/análogos & derivados , Epitestosterona/urina , Detecção do Abuso de Substâncias/métodos , Androsterona/urina , Dopagem Esportivo , Epitestosterona/farmacocinética , Etiocolanolona/urina , Humanos , Modelos Lineares , Masculino , Pregnanodiol/urina , Valores de Referência , Reprodutibilidade dos Testes
10.
Drug Test Anal ; 1(2): 65-72, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20355178

RESUMO

In order to detect the misuse of endogenous anabolic steroids such as testosterone by athletes a total of n = 1734 suspicious urine samples were investigated by gas chromatography/combustion/isotope ratio mass spectrometry throughout the years 2005, 2006 and 2007. The (13)C/(12)C ratio of a target substance (androsterone, a testosterone metabolite) was compared to the (13)C/(12)C ratio of an endogenous reference compound (11beta-hydroxyandrosterone).N = 1340 samples were investigated due to elevated testosterone/epitestosterone ratios, with n = 87 (6.5%) exceptional findings regarding their isotopic ratios. An additional n = 164 samples were investigated because of elevated dehydroepiandrosterone concentrations, with n = 2 (1.2%) exceptional findings. The remainder were subjected to isotope ratio analysis because of elevated androsterone levels or because this was requested by sports federations.Significant differences between female and male samples were found for the (13)C/(12)C ratios of androsterone and 11beta-hydroxyandrosterone but not for samples taken in or out of competition.A further n = 645 samples originating from other World Anti-Doping Agency accredited laboratories, mainly throughout Europe as well as South America, South Africa and Southeast Asia, were investigated. The (13)C/(12)C ratios of the urinary steroids differ significantly for each geographical region, reflecting the dietary status of the individuals.The system stability over time has been tested by repeated injections of a standard solution and repeated processing of frozen stored blank urine. Despite a drift over time in absolute (13)C/(12)C ratios, no significant change in the difference of (13)C/(12)C (11beta-hydroxyandrosterone) minus (13)C/(12)C (androsterone) could be observed.


Assuntos
Anabolizantes/urina , Dopagem Esportivo , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Testosterona/urina , Androsterona/urina , Carbono/urina , Isótopos de Carbono/urina , Desidroepiandrosterona/urina , Epitestosterona/urina , Feminino , Humanos , Masculino , Testosterona/metabolismo
11.
J Sports Sci ; 26(10): 1059-65, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18608840

RESUMO

Drug abuse by adolescents has been investigated in various surveys that reported correlations between age, gender, and activity. However, none of these studies included chemical analyses to help substantiate the statements of participants. In the present study, the urine specimens of 964 students (439 females, 525 males; mean age 22.1 years, s = 1.7), who applied to study sports sciences at university, were assessed for anabolic steroids, stimulants, and selected drugs prohibited in sports. In total, 11.2% of the urine specimens provided contained drugs covered by doping controls. The most frequently detected compound was the major metabolite of tetrahydrocannabinol (9.8%) followed by various stimulants related to amphetamine and cocaine (1.0%). Indications of anabolic steroid use were found in 0.4% of urine samples but originated from contraceptives containing norethisterone. The present study provided unambiguous data on the status quo of drug (ab)use by adolescents hoping for a career related to elite sport or sports sciences. No use of anabolic steroids was detected. However, evidence for stimulants and tetrahydrocannabinol administration was obtained, although not reported by any participant, which highlights the issue of under-reporting in surveys based solely on questionnaires.


Assuntos
Anabolizantes/urina , Estimulantes do Sistema Nervoso Central/urina , Dopagem Esportivo/estatística & dados numéricos , Estudantes , Detecção do Abuso de Substâncias/métodos , Detecção do Abuso de Substâncias/estatística & dados numéricos , Anfetamina/urina , Cocaína/urina , Dronabinol/urina , Feminino , Alemanha , Humanos , Masculino , Espectrometria de Massas , Prevalência , Psicotrópicos/urina , Esportes/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Inquéritos e Questionários , Adulto Jovem
12.
Rapid Commun Mass Spectrom ; 22(14): 2161-75, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18536069

RESUMO

The application of a comprehensive gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS)-based method for stable carbon isotopes of endogenous urinary steroids is presented. The key element in sample preparation is the consecutive cleanup with high-performance liquid chromatography (HPLC) of underivatized and acetylated steroids, which allows the isolation of ten analytes (11beta-hydroxyandrosterone, 5alpha-androst-16-en-3beta-ol, pregnanediol, androsterone, etiocholanolone, testosterone, epitestosterone, 5alpha-androstane-3alpha,17beta-diol, 5beta-androstane-3alpha,17beta-diol and dehydroepiandrosterone) from a single urine specimen. These steroids are of particular importance to doping controls as they enable the sensitive and retrospective detection of steroid 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 repeatability and reproducibility. Specificity was further demonstrated by gas chromatography/mass spectrometry (GC/MS) 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 of all implemented steroids, a reference population of n = 61 subjects was measured to enable the calculation of reference limits for all relevant steroidal Delta values.


Assuntos
Anabolizantes/urina , Dopagem Esportivo , Esteroides/urina , Adulto , Isótopos de Carbono , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Géis , Humanos , Marcação por Isótopo , Masculino , Padrões de Referência , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testosterona/administração & dosagem , Testosterona/farmacocinética , Testosterona/urina
13.
J Mass Spectrom ; 43(7): 892-902, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18563865

RESUMO

Since 1999 several groups have analyzed nutritional supplements with mass spectrometric methods (GC/MS, LC/MS/MS) for contaminations and adulterations with doping substances. These investigations showed that nutritional supplements contained prohibited stimulants as ephedrines, caffeine, methylenedioxymetamphetamie and sibutramine, which were not declared on the labels. An international study performed in 2001 and 2002 on 634 nutritional supplements that were purchased in 13 different countries showed that about 15% of the nonhormonal nutritional supplements were contaminated with anabolic-androgenic steroids (mainly prohormones). Since 2002, also products intentionally faked with high amounts of 'classic' anabolic steroids such as metandienone, stanozolol, boldenone, dehydrochloromethyl-testosterone, oxandrolone etc. have been detected on the nutritional supplement market. These anabolic steroids were not declared on the labels either. The sources of these anabolic steroids are probably Chinese pharmaceutical companies, which sell bulk material of anabolic steroids. In 2005 vitamin C, multivitamin and magnesium tablets were confiscated, which contained cross-contaminations of stanozolol and metandienone. Since 2002 new 'designer' steroids such as prostanozol, methasterone, androstatrienedione etc. have been offered on the nutritional supplement market. In the near future also cross-contaminations with these steroids are expected. Recently a nutritional supplement for weight loss was found to contain the beta2-agonist clenbuterol. The application of such nutritional supplements is connected with a high risk of inadvertent doping cases and a health risk. For the detection of new 'designer' steroids in nutritional supplements, mass spectrometric strategies (GC/MS, LC/MS/MS) are presented.


Assuntos
Anabolizantes/análise , Suplementos Nutricionais/análise , Dopagem Esportivo , Contaminação de Medicamentos , Detecção do Abuso de Substâncias/métodos , Artefatos , Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectrometria de Massas em Tandem
14.
J Mass Spectrom ; 43(7): 877-91, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18570179

RESUMO

Steroid profiling is one of the most versatile and informative screening tools for the detection of steroid abuse in sports drug testing. Concentrations and ratios of various endogenously produced steroidal hormones, their precursors and metabolites including testosterone (T), epitestosterone (E), dihydrotestosterone (DHT), androsterone (And), etiocholanolone (Etio), dehydroepiandrosterone (DHEA), 5alpha-androstane-3alpha,17beta-diol (Adiol), and 5beta-androstane-3alpha,17beta-diol (Bdiol) as well as androstenedione, 6alpha-OH-androstenedione, 5beta-androstane-3alpha,17alpha-diol (17-epi-Bdiol), 5alpha-androstane-3alpha,17alpha-diol (17-epi-Adiol), 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo), 5alpha-androstanedione (Adion), and 5beta-androstanedione (Bdion) add up to a steroid profile that is highly sensitive to applications of endogenous as well as synthetic anabolic steroids, masking agents, and bacterial activity. Hence, the knowledge of factors that do influence the steroid profile pattern is a central aspect, and pharmaceutical (application of endogenous steroids and various pharmaceutical preparations), technical (hydrolysis, derivatization, matrix), and biological (bacterial activities, enzyme side activities) issues are reviewed.


Assuntos
Anabolizantes/urina , Dopagem Esportivo , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Gravidez
15.
Ther Drug Monit ; 29(2): 236-47, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17417080

RESUMO

5alpha-Reductase inhibitors such as finasteride are prohibited in sports according to the World Anti-Doping Agency. This class of drugs is used therapeutically to treat benign prostatic hyperplasia, as well as male baldness, by decreasing 5alpha-reductase activity. Accordingly, metabolic pathways of endogenous as well as synthetic steroids are influenced, which complicates the evaluation of steroid profiles in sports drug testing. The possibility of manipulating steroid excretion profiles and, presumably, to mask steroid abuse was investigated in 5 administration studies with use of finasteride at different doses, with and without coadministration of 19-norandrostenedione. The evaluation of urinary steroid profiles demonstrated the intense effect of finasteride on numerous crucial analytical parameters, in particular the production of 5alpha-steroids such as androsterone and 5alpha-androstane-3alpha,17beta-diol, which was significantly reduced. In addition, the excretion of the main metabolite of norandrostenedione, norandrosterone, was significantly suppressed, by up to 84%, in elimination studies. For doping-control analysis the use of 5alpha-reductase inhibitors causes considerable problems because steroid profile parameters, which are commonly considered stable, are highly affected and complicate the detection of steroid abuse. In addition, the suppression of production and renal excretion of 5alpha-steroids such as 19-norandrosterone generated from anabolic agents such as 19-norandrostenedione may lead to false-negative doping-control results, because urine specimens are reported positive only when a threshold level of 2 ng/mL is exceeded. Finally, a method for the determination of the major urinary metabolite of finasteride (carboxy-finasteride) in routine doping-control screening with use of liquid chromatography-tandem mass spectrometry is described, allowing the detection of carboxy-finasteride for up to 94 hours in urine specimens collected after an oral administration of 5 mg of finasteride.


Assuntos
Androstenodiona/análogos & derivados , Colestenona 5 alfa-Redutase/antagonistas & inibidores , Dopagem Esportivo , Inibidores Enzimáticos/farmacologia , Finasterida/análogos & derivados , Finasterida/farmacologia , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Adulto , Androstenodiona/farmacocinética , Cromatografia Líquida , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/análise , Finasterida/análise , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
16.
Anal Bioanal Chem ; 388(7): 1539-43, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17260133

RESUMO

Manipulation of urine sampling in sports drug testing is considered a violation of anti-doping rules and is consequently sanctioned by regulatory authorities. In 2003, three identical urine specimens were provided by three different athletes, and the identity of all urine samples was detected and substantiated using numerous analytical strategies including gas chromatography-mass spectrometry with steroid and metabolite profiling, gas chromatography-nitrogen/phosphorus detector analysis, high-performance liquid chromatography-UV fingerprinting, and DNA-STR (short tandem repeat) analysis. None of the respective athletes was the donor of the urine provided for doping analysis, which proved to be a urine sample collected from other unidentified individual(s). Samples were considered suspicious based on identical steroid profiles, one of the most important parameters for specimen individualization in sports drug testing. A database containing 14,224 urinary steroid profiles of athletes was screened for specific values of 4 characteristic parameters (ratios of testosterone/epitestosterone, androsterone/etiocholanolone, androsterone/testosterone, and 5alpha-androstane-3alpha,17beta-diol/5beta-androstane-3alpha,17beta-diol) and only the three suspicious samples matched all criteria. Further metabolite profiling regarding indicated medications and high-performance liquid chromatography-UV fingerprinting substantiated the assumption of manipulation. DNA-STR analyses unequivocally confirmed that the 3 urine samples were from the same individual and not from the athletes who provided DNA from either buccal cell material or blood specimens. This supportive evidence led to punishment of all three athletes according to the rules of the World Anti-Doping Agency. Application of a new multidisciplinary strategy employing common and new doping control assays enables the detection of urine substitution in sports drug testing.


Assuntos
Enganação , Dopagem Esportivo/legislação & jurisprudência , Manejo de Espécimes/normas , Urina , Humanos , Preparações Farmacêuticas/metabolismo , Detecção do Abuso de Substâncias/legislação & jurisprudência , Detecção do Abuso de Substâncias/normas
17.
Eur J Mass Spectrom (Chichester) ; 13(6): 419-26, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18417762

RESUMO

According to World Anti-Doping Agency (WADA) rules (WADA Technical Document-TD2004EAAS) urine samples containing dehydroepiandrosterone (DHEA) concentrations greater than 100 ng ML(-1) shall be submitted to isotope ratio mass spectrometry (IRMS) analysis. The threshold concentration is based on the equivalent to the glucuronide, and the DHEA concentrations have to be adjusted for a specific gravity value of 1.020. In 2006, 11,012 doping control urine samples from national and international federations were analyzed in the Cologne doping control laboratory, 100 (0.9%) of them yielding concentrations of DHEA greater than 100 ng mL(-1). Sixty-eight percent of the specimens showed specific gravity values higher than 1.020, 52% originated from soccer players, 95% were taken in competition, 85% were male urines, 99% of the IRMS results did not indicate an application of testosterone or related prohormones. Only one urine sample was reported as an adverse analytical finding having 319 ng mL(-1) DHEA (screening result), more than 10,000 ng mL(-1) androsterone and depleted carbon isotope ratio values for the testosterone metabolites androsterone and etiocholanolone. Statistical evaluation showed significantly different DHEA concentrations between specimens taken in- and out-of- competition, whereas females showed smaller DHEA values than males for both types of control. Also a strong influence of the DHEA excretion on different sport disciplines was detectable. The highest DHEA values were detected for game sports (soccer, basketball, handball, ice hockey), followed by boxing and wrestling. In 2007, 6622 doping control urine samples were analyzed for 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo), a DHEA metabolite which was described as a useful gas chromatography-mass spectrometry (GC-MS) screening marker for DHEA abuse. Nineteen urine specimens showed concentrations higher than the suggested threshold of 140 ng mL(-1), six urine samples yielded additionally DHEA concentrations higher than 100 ng mL(-1), none of them showing positive IRMS findings. These results should be taken into consideration in future discussions about threshold values for endogenous steroids in doping control.


Assuntos
Desidroepiandrosterona/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Feminino , Humanos , Masculino , Valores de Referência
18.
Biomed Chromatogr ; 21(2): 164-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17146762

RESUMO

In numerous studies it has been demonstrated that several nutritional supplements contain prohormones not declared on the label. In the current study two products (effervescent tablets) containing high amounts of the 17-methylated anabolic androgenic steroids metandienone (product 1: 16.8 mg/tablet) and stanozolol (product 2: 14.5 mg/tablet) were identified. Additionally in both products norandrostenedione was detected, in product 2 with minor amounts of several other steroids. The substances identified can cause enormous health risks. In addition, the use of the analyzed tablets can lead to positive doping results for metabolites of the respective steroids in sports. This study again shows the insufficient surveillance of the production and trade of dietary supplements. Consumers should be aware of the enormous health and doping risks connected with the use of such products. For GC-MS identification of the analytes the trimethylsilyl derivatives of the steroids and the mixed N-t-butyldimethylsilyl,O-trimethylsilyl derivatives were used. The quantitation of metandienone, norandrostenedione, and stanozolol was performed using HPLC-DAD.


Assuntos
Anabolizantes/análise , Androgênios/análise , Suplementos Nutricionais/análise , Metandrostenolona/análise , Estanozolol/análise , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/normas , Dopagem Esportivo/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Trimetilsilil/análise , Compostos de Trimetilsilil/química
19.
Analyst ; 131(9): 1021-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17047802

RESUMO

On the one hand, 19-norandrosterone (NA) is the most abundant metabolite of the synthetic anabolic steroid 19-nortestosterone and related prohormones. On the other hand, small amounts are biosynthesized by pregnant women and further evidence exists for physiological origin of this compound. The World Anti-Doping Agency (WADA) formerly introduced threshold concentrations of 2 or 5 ng of NA per ml of urine to discriminate 19-nortestosterone abuse from biosynthetic origin. Recent findings showed however, that formation of NA resulting in concentrations in the range of the threshold levels might be due to demethylation of androsterone in urine, and the WADA 2006 Prohibited List has defined NA as endogenous steroid. To elucidate the endogenous or exogenous origin of NA, (13)C/(12)C-analysis is the method of choice since synthetic 19-nortestosterone is derived from C(3)-plants by partial synthesis and shows delta(13)C(VPDB)-values of around -28 per thousand. Endogenous steroids are less depleted in (13)C due to a dietary mixture of C(3)- and C(4)-plants. An extensive cleanup based on two high performance liquid chromatography cleanup steps was applied to quality control and doping control samples, which contained NA in concentrations down to 2 ng per ml of urine. (13)C/(12)C-ratios of NA, androsterone and etiocholanolone were measured by gas chromatography/combustion/isotope ratio mass spectrometry. By comparing delta(13)C(VPDB)-values of androsterone as endogenous reference compound with NA, the origin of NA in doping control samples was determined as either endogenous or exogenous.


Assuntos
Isótopos de Carbono/urina , Dopagem Esportivo , Estranos/urina , Detecção do Abuso de Substâncias/métodos , Etiocolanolona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Nandrolona/urina , Extratos Vegetais
20.
Rapid Commun Mass Spectrom ; 20(12): 1954-62, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16715475

RESUMO

Anastrozole (2,2'-[5-(1H-1,2,4-triazol-1-ylmethyl)-1.3-phenylene]bis(2-methylpropionitrile)) and exemestane (6-methylenandrostan-1,4-diene-3,17-dione) are therapeutically used to treat hormone-sensitive breast cancer in postmenopausal women. For doping purposes they may be used to counteract adverse effects of an extensive abuse of anabolic androgenic steroids (gynaecomastia) and to increase plasma testosterone concentrations. Excretion study urine samples and spot urine samples from women suffering from metastatic breast cancer, being treated with anastrozole or exemestane, were collected and analyzed to develop/optimize a detection system for anastrozole and exemestane to allow the identification of athletes who do not comply with the internationally prohibited use of these cancer drugs. The assay was based on liquid-liquid extraction after enzymatic hydrolysis following liquid chromatography/tandem mass spectrometry (LC/MS/MS). Anastrozole, exemestane and its main metabolite (17-dihydroexemestane) were identified in urine by comparison of mass spectra and retention times with respective reference substances. An assay validation for the analysis of anastrozole and exemestane was performed regarding lower limits of detection (anastrozole: 0.02 ng/mL; exemestane: 3.1 ng/mL; dihydroexemestane: 0.5 ng/mL), interday precisions (6.6-11.1%, 4.9-9.1% and 5.6-8.3% for low [10 ng/mL], medium [50 ng/mL] and high [100 ng/mL] concentration) and recoveries (ranged from 85-97%).


Assuntos
Androstadienos/urina , Antineoplásicos Hormonais/urina , Inibidores da Aromatase/urina , Cromatografia Líquida de Alta Pressão , Nitrilas/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Triazóis/urina , Anastrozol , Androstadienos/farmacocinética , Androstadienos/uso terapêutico , Antineoplásicos Hormonais/farmacocinética , Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/farmacocinética , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/secundário , Feminino , Humanos , Masculino , Nitrilas/farmacocinética , Nitrilas/uso terapêutico , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/métodos , Triazóis/farmacocinética , Triazóis/uso terapêutico
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