Contamination of dietary supplements and positive drug tests in sport

Abstract

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.

The application of reporter gene assays for the detection of endocrine disruptors in sport supplements

“…Furthermore, of concern is that this study obtained a positive hormonal response in more then 70% of the tested products. This reinforces increasing publicised data about the presence of EDs in healthfood supplements [12,13,27].…”

“…The 'General Food Law Regulation' clearly specifies that medicinal products should not be included in any type of food. However, concerns over the accidental, environmental or deliberate contamination of sport supplements during the manufacturing process or from the raw ingredients have been highlighted in an increasing number of studies reporting the contamination of sport supplements with hormonally active substances [12,13]. Delbeke et al reported the significant presence of pro-hormones and hormones in two sport supplements which did not have hormonal substances listed on the product label [14].…”

Suspected Adulteration of Commercial Kratom Products with 7-Hydroxymitragynine

“…Adulteration is an exemplary repercussion of such laxity. Well documented are instances of diuretics, stimulants, anorectics, or oxidative uncouplers contained in weight loss supplements [60][61][62][63][64][65][66][67][68][69][70][71][72][73][74], steroids in performance enhancers [75][76][77][78][79][80], and phosphodiesterase 5 inhibitors contained within male enhancement products [72,74,[81][82][83][84][85][86][87][88][89][90][91][92][93]. At least nine people died in Sweden following exposure to Kratom adulterated with Odesmethyltramadol, a potent opioid analgesic.…”

Nutrition for sports performance: issues and opportunities

“…A concern with many supplements on sale, apart from the lack of evidence of efficacy and safety, is the recent spate of reports of contamination of supplements with prohibited substances, including stimulants and anabolic steroids (50) . The amounts present are generally, though not always, too small to be effective in improving performance or to pose a risk to health but can cause a positive drugs test (51) .…”