Contamination of dietary supplements and positive drug tests in sport
School of Sport and Exercise Sciences, Loughborough University, Loughborough LE11 3TU, UK. Journal of Sports Sciences
(Impact Factor: 2.25).
10/2005; 23(9):883-9. DOI: 10.1080/02640410400023258
The use of dietary supplements is widespread in sport and most athletes competing at the highest level of competition use some form of dietary supplementation. Many of these supplements confer no performance or health benefit, and some may actually be detrimental to both performance and health when taken in high doses for prolonged periods. Some supplements contain excessive doses of potentially toxic ingredients, while others do not contain significant amounts of the ingredients listed on the label. There is also now evidence that some of the apparently legitimate dietary supplements on sale contain ingredients that are not declared on the label but that are prohibited by the doping regulations of the International Olympic Committee and of the World Anti-Doping Agency. Contaminants that have been identified include a variety of anabolic androgenic steroids (including testosterone and nandrolone as well as the pro-hormones of these compounds), ephedrine and caffeine. This contamination may in most cases be the result of poor manufacturing practice, but there is some evidence of deliberate adulteration of products. The principle of strict liability that applies in sport means that innocent ingestion of prohibited substances is not an acceptable excuse, and athletes testing positive are liable to penalties. Although it is undoubtedly the case that some athletes are guilty of deliberate cheating, some positive tests are likely to be the result of inadvertent ingestion of prohibited substances present in otherwise innocuous dietary supplements.
Available from: Herve Rebiere
- "They are labelled as pro-hormones (supposed to promote the production of natural steroid hormones), but some contain a significant quantity of anabolic steroids and could cause a positive doping control.      Baume et al. "
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ABSTRACT: The use of performance enhancing drugs is a widespread phenomenon in professional and leisure sports. A spectroscopic study was carried out on anabolic tablets labelled as 5 mg methandienone tablets provided by police departments. The analytical approach was based on a two-step methodology: a fast analysis of tablets using near infrared (NIR) spectroscopy to assess sample homogeneity based on their global composition, followed by Raman chemical imaging of one sample per NIR profile to obtain information on sample formulation. NIR spectroscopy assisted by a principal components analysis (PCA) enabled fast discrimination of different profiles based on the excipient formulation. Raman hyperspectral imaging and multivariate curve resolution - alternating least square (MCR-ALS) provided chemical images of the distribution of the active substance and excipients within tablets and facilitated identification of the active compounds. The combination of NIR spectroscopy and Raman chemical imaging highlighted dose-to-dose variations and succeeded in the discrimination of four different formulations out of eight similar samples of anabolic tablets. Some samples contained either methandienone or methyltestosterone whereas one sample did not contain an active substance. Other ingredients were sucrose, lactose, starch or talc. Both techniques were fast and non-destructive and therefore can be carried out as exploratory methods prior to destructive screening methods. Copyright © 2015 John Wiley & Sons, Ltd.
Copyright © 2015 John Wiley & Sons, Ltd.
Drug Testing and Analysis 07/2015; DOI:10.1002/dta.1843 · 2.51 Impact Factor
Available from: David B Pyne
- "In this context, it is also important to remember that some probiotic products contain energy and carbohydrate that can form part of an athlete's overall nutrition plan. Only reputable sources of commercially available supplements should be used to reduce the risk of contaminants that might contravene doping in sport regulations (Maughan, 2005). Athletes should be educated on the likely risks of contamination given that the World Anti-Doping Agency enforces a principle of strict liability for positive test results involving banned substances. "
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ABSTRACT: Abstract Probiotic supplementation has traditionally focused on gut health. However, in recent years, the clinical applications of probiotics have broadened to allergic, metabolic, inflammatory, gastrointestinal and respiratory conditions. Gastrointestinal health is important for regulating adaptation to exercise and physical activity. Symptoms such as nausea, bloating, cramping, pain, diarrhoea and bleeding occur in some athletes, particularly during prolonged exhaustive events. Several studies conducted since 2006 examining probiotic supplementation in athletes or highly active individuals indicate modest clinical benefits in terms of reduced frequency, severity and/or duration of respiratory and gastrointestinal illness. The likely mechanisms of action for probiotics include direct interaction with the gut microbiota, interaction with the mucosal immune system and immune signalling to a variety of organs and systems. Practical issues to consider include medical and dietary screening of athletes, sourcing of recommended probiotics and formulations, dose-response requirements for different probiotic strains, storage, handling and transport of supplements and timing of supplementation in relation to travel and competition.
European Journal of Sport Science 10/2014; 15(1):1-10. DOI:10.1080/17461391.2014.971879 · 1.55 Impact Factor
Available from: Declan Naughton
- "In addition, large scale studies are based on self-reports where owing to the negative connotations attached to doping, respondents are believed to be subject to a reporting bias, thus skewing results of individual studies as well as the research area as a whole on doping. On the other hand, a plethora of dietary supplements is available on the market with proven and putative effects on sport performance, some being on a par with prohibited substances (Maughan, 2005; Maughan, Greenhaff, & Hespel, 2011). Hormone-boosting herbal supplements (HS) can be bought from most herbal shops. "
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This paper compares two indirect prevalence estimation methods that offer protection beyond anonymity and are suitable for self-administration, for investigating the epidemiology of transgressive or socially sensitive behaviours.DesignIn this self-report study, 513 participants (58.7% male) from sports clubs across the UK and southern Ireland were asked to complete an anonymous survey containing the recently developed Single Sample Count (SSC), along with a comparative method Unrelated Question Model (UQM), using prohibited performance-enhancing drugs/substances (PED) as sensitive and hormone-boosting herbal supplements (HS) as non-sensitive control questions.Method
The survey comprised of sections of SSC, UQM, social projection and simple network scale up methods. Respondents were asked to indicate whether they preferred the SSC or UQM for more protection and ease of completion.ResultsA large discrepancy was observed in prevalence estimates for PED using the UQM (58.4%) and SSC (19.8%), but not for HS (54.9% and 54.0%, respectively). The SSC prevalence estimate for PED was in keeping with the results from social projection (13.8% in own sport; 26.1% in all sports) and network scale up (19.3% for known and suspected doping combined). A clear preference was logged for SSC.ConclusionSSC, but not UQM, showed good concurrent validity with social projection and personal networks for PED; and good discriminant validity with HS. The observed discrepancy could be explained by strategic responding which can inflate the proportion of ‘yes’ answers in the UQM. Adaptation of the UQM for self-administration may lead to an unwanted upward response distortion via strategic responding.
Psychology of Sport and Exercise 01/2013; 14(1):84–96. DOI:10.1016/j.psychsport.2012.08.003 · 1.90 Impact Factor
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