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1.
Med Sport Sci ; 59: 143-152, 2012.
Article in English | MEDLINE | ID: mdl-23075565

ABSTRACT

Despite ongoing improvements to regulatory and manufacturing guidelines, the potential for contaminated nutritional supplements to cause a failed doping test for an athlete remains a concern. Several surveys of supplements available through the internet and at retail have confirmed that many are contaminated with steroids and stimulants that are prohibited for use in elite sport. Suggested responses to this issue include the complete avoidance of all supplements. However, this approach seems to be unrealistic as many athletes use nutritional supplements for very different reasons. In addition, the number of publications describing trials that demonstrate the benefit of certain nutritional products has also increased over the last decade or so. This ensures that for many sports the use of supplements will remain a common practice. In response to the issue of contamination in nutritional supplements, many reputable manufacturers have their products rigorously tested by sports anti-doping laboratories to help ensure as far as possible that the risks to an athlete remain minimal. In this chapter we review the issue of supplements and contamination, and look at how this might be addressed through effective quality control procedures at the manufacturing facility and through the highly sensitive testing of finished products using appropriately accredited tests.


Subject(s)
Consumer Product Safety , Dietary Supplements/adverse effects , Doping in Sports/methods , Drug Contamination/prevention & control , Sports Medicine , Health Status , Humans , Nutritional Status
2.
Drug Test Anal ; 2(9): 417-20, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20812298

ABSTRACT

The potential for contaminated dietary supplements to result in a failed doping test remains a concern for athletes, trainers, and sporting authorities despite improvements to regulatory guidelines. Previous surveys of readily available supplements confirm that many are contaminated with steroids and stimulants prohibited for use in elite sport. Suggested responses to this issue include the complete avoidance of all supplements. Many athletes, however, use nutritional supplements to achieve effective training and also to ensure that daily nutritional requirements are met (e.g. recommended levels of vitamins and minerals). This ensures that the use of supplements is and will remain the norm for a range of sports. As a result, an alternative approach of rigorous testing of materials destined for use by elite athletes has been introduced in several countries. While the testing of final product for banned substances may help mitigate the problem, it will not help to remove the underlying issue of contamination. In this article we describe an alternative approach that uses appropriate quality assurance procedures backed up by testing to remove sources of contamination. The decrease in the incidence of contamination amongst supplement companies adopting such a system is explained, and contrasted with the relatively high incidences of contamination found in products that are not part of a quality system. These findings are of key importance to both supplement manufacturers and those involved in advising athletes about supplement use.


Subject(s)
Dietary Supplements/standards , Doping in Sports , Drug Contamination , Drug Residues/analysis , Dietary Supplements/analysis , Humans , Quality Control
3.
Med Sci Sports Exerc ; 42(4): 754-61, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19952830

ABSTRACT

INTRODUCTION: This study examined the influence of a supplement matrix on the excretion pattern of nandrolone metabolites in response to ingestion of a trace amount of 19-norandrostenedione. METHODS: Ten male and nine female volunteers (mean ± SD: age = 26 ± 3 yr, height = 1.71 ± 0.09 m, body mass = 70.9 ± 13.2 kg) were recruited. On two occasions, subjects entered the laboratory in the morning after an overnight fast. After an initial urine collection, subjects ingested either 500 mL of plain water or a commercially available energy bar; 10 µg of 19-norandrostenedione was added to each. The volume of each urine sample passed during the next 24 h was measured, and an aliquot was retained for analysis. All samples were analyzed for the metabolites 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) by gas chromatography-mass spectrometry. RESULTS: The total volume of urine passed was higher in the water trial (2.10 ± 0.52 L) than in the bar trial (1.85 ± 0.55 L; P = 0.040). Baseline urinary 19-NA concentrations were all below the limit of quantification for the assay. Peak urinary 19-NA was lower (P = 0.002) in the water trial (4.80 ± 2.84 ng·mL(-1)) than in the bar trial (8.46 ± 4.44 ng·mL(-1)). The time elapsed between ingestion of the supplement and the peak urinary 19-NA concentration was longer (P = 0.023) on the bar trial (4.6 ± 2.4 h) than on the water trial (2.8 ± 1.9 h). There was no difference in the total recovery of 19-NA + 19-NE between the liquid and solid supplements (water 30 ± 10%; bar 28 ± 12%; P < 0.140). CONCLUSIONS: Peak 19-NA concentrations were higher, and occurred later, when the 19-norandrostenedione was added to a solid supplement. This may be due to a slower rate of absorption and/or a reduced diuresis, resulting in a longer period for the metabolites to accumulate in the urine.


Subject(s)
Anabolic Agents/administration & dosage , Androstenedione/analogs & derivatives , Dietary Supplements , Nandrolone/urine , Adsorption , Adult , Anabolic Agents/pharmacokinetics , Androstenedione/administration & dosage , Androstenedione/pharmacokinetics , Doping in Sports , Drinking , Eating , Female , Gas Chromatography-Mass Spectrometry , Humans , Male , Young Adult
4.
Med Sci Sports Exerc ; 41(4): 766-72, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19276858

ABSTRACT

INTRODUCTION: Quantities of various anabolic/androgenic steroids have been found in dietary supplements without their presence being disclosed on the label. The aim of this study was to quantify the excretion patterns of the diagnostic metabolites, 19-norandrosterone (19-NA), and 19-noretiocholanolone (19-NE) after ingestion of small doses of 19-nor-4-androstene-3,17-dione (19-norandrostenedione). METHODS: Eleven males and nine females entered the laboratory in the morning after an overnight fast. An initial urine sample was collected, and volunteers then ingested 500 mL of water containing 5 g of creatine monohydrate and 1.0, 2.5, or 5.0 microg of 19-norandrostenedione. The volume of each urine void was measured, and an aliquot was taken. Samples were analyzed for the metabolites 19-NA and 19-NE by GCMS. RESULTS: Baseline urinary 19-NA concentrations were 0.19 +/- 0.14 ng x mL. Ingestion of the supplement resulted in peak mean urinary 19-NA concentrations of 0.68 +/- 0.36, 1.56 +/- 0.86, and 3.89 +/- 3.11 ng.mL in the 1.0-, 2.5-, or 5.0-microg trials, respectively. Under current WADA regulations, ingestion of the 1.0-microg dose produced 0 positive doping tests, 5 subjects (20%) tested positive in the 2.5-microg trial, and 15 subjects (75%) had urinary 19-NA concentrations exceeding 2 ng x mL after ingesting creatine containing 5.0 microg of the steroid. The recovery of the ingested dose was highly variable between individuals, with values ranging from 11% to 84% (mean +/- SD = 47% +/- 18%). CONCLUSIONS: Ingestion of trace amounts of 19-norandrostenedione can result in transient elevations of urinary 19-NA and 19-NE concentrations. The addition of as little as 2.5 microg of 19-norandrostenedione to a supplement (0.00005% contamination) appears sufficient to result in a doping violation in some individuals.


Subject(s)
Androstenedione/analogs & derivatives , Estranes/urine , Nandrolone/urine , Adult , Androstenedione/administration & dosage , Androstenedione/metabolism , Androstenedione/urine , Creatine/administration & dosage , Doping in Sports , Estranes/metabolism , Female , Humans , Male , Young Adult
5.
Eur J Pharm Biopharm ; 53(1): 9-14, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11777747

ABSTRACT

To investigate variability in dissolution testing an international collaborative study was performed by 29 laboratories. Glibenclamide (glyburide) tablets were used in the investigation in which multipoint dissolution profiles were established using USP paddle apparatus. In contrast to a previous report, the variability of the glibenclamide dissolution data was significantly lower. Total variances (s(2)) were found to range from 18.34-44.18, Between Laboratory and Between Analyst variances (synthetic value) ranged from 12.9-38.7 and the Within Analyst variances ranged from 5.08-5.78. The dissolution profiles and corresponding variances obtained by laboratories with little or no experience in glibenclamide dissolution testing were similar to those obtained by more experienced laboratories, indicating that the test, especially when designed as multiple point dissolution testing, is sufficiently robust and capable of identifying differences in a manufacturing process or drug formulation. The smallest statistically detectable mean difference between two dissolution runs was calculated (95% CI) to be 7% for one analyst, or 5% if two analysts were to perform the dissolution tests.


Subject(s)
Drug Evaluation, Preclinical/statistics & numerical data , Pharmaceutical Preparations/chemistry , Drug Evaluation, Preclinical/methods , Solubility , Technology, Pharmaceutical/methods , Technology, Pharmaceutical/statistics & numerical data
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