Bovengrens dopingrisico sportvoedingssupplementen: Onderzoek naar de aanwezigheid van dopingstoffen in hoog-risico-sportvoedingssupplementen verkrijgbaar in Nederlandse webshops / Erik Duiven, Olivier de Hon, Laila Spruijt en Bart Coumans . - Capelle aan den IJssel : Dopingautoriteit, 2015
Various studies have shown that dietary supplements can contain prohibited substances without this being stated clearly on the label. In response to this risk for elite athletes, the Doping Authority established the Dutch Safeguards System for Dietary Supplements in Elite Sport (NZVT). It is reasonable to assume that prohibited substances will seldom or never be added deliberately to dietary supplements submitted for analysis under the NZVT system. Nevertheless, between 2003 and 2014, eighteen of the product-batch combinations submitted (1.6%) were found to contain prohibited substances. This percentage is considered to be the lower limit for the prevalence of prohibited substances in dietary supplements. Little or nothing is known about where the upper limit is to be found. International studies have reported maximum upper limits of around 25%. However, the actual upper limit was actually expected to be much higher, especially in a group of highrisk sports supplements specifically targeting hormone regulation, strengthening muscle, weight loss/burning fat, or raising energy levels. This study focused on the question of what percentage of these high-risk sports supplements contain prohibited substances.
After a selection was made from seventeen different web shops, 66 products from 21 different brands were submitted for analysis to the LGC research laboratory (United Kingdom). Twenty-five (38%) of the high-risk sports supplements tested ‘positive’ and 30 (45%) tested ‘negative’. Eight products (12%) were found to contain ‘concentrations below the adopted threshold value’. In these cases, the detection of doping substances may be explained by their natural presence in certain ingredients, such as botanical components. However, this cannot be stated with certainty. Specific research in this area is therefore required. Three of the 66 products (5%) were 'not analysable/not fully analysable'. Three of the 25 'positive' products (5% of the total sample analysed) were found to contain prohibited substances in high concentrations. In addition to the real risk these products pose for athletes in terms of doping violations, there is also a genuine health risk. Given the public health implications, these findings were therefore reported to the Netherlands Food and Consumer Product Safety Authority (NVWA).
This study shows that Dutch elite athletes continue to be exposed to risks if they use product-batch combinations of dietary supplements that have not been tested for the presence of doping substances by the NZVT (or any other recognised system). At the same time, the NZVT is not used by large proportion - or even a majority - of Dutch elite athletes. This is an undesirable situation. It will therefore be important to boost the promotion of the NZVT among these elite athletes.
Recommendations
NZVT
This study shows that Dutch elite athletes will continue to be exposed to risks if they use product-batch combinations of dietary supplements that have not been tested for the presence of doping substances by the NZVT (or any other recognised system). At the same time, the NZVT is not used by large proportion - or even a majority - of elite Dutch athletes. It is therefore important to give an additional boost to the promotion of the NZVT among elite athletes in the Netherlands. In addition, elite Dutch athletes state that the number of products in the NZVT is limited. Despite the fact that the number of approved product-batch combinations has been growing steadily in recent years, it would therefore also be
desirable to encourage the use of the NZVT by manufacturers of dietary supplements available in the Netherlands.
Netherlands Food and Consumer Product Safety Authority (NVWA) High concentrations of prohibited substances were found in three dietary supplements from two different companies. Using these products could easily result in health problems. Given the public health implications, these findings were therefore reported to the Netherlands Food and Consumer Product Safety Authority (NVWA). This implies a request for the launch of a further investigation into these three dietary supplements.
Botanical components
It would appear to be the case that an increasing number of sports supplements contain botanical ingredients. The addition of these botanical ingredients would also seem to result in findings of low concentrations of steroids. Although phytochemical studies have already demonstrated this principle, the production process used for supplements may lead to an increase in these natural concentrations. This could be a partial explanation for the relatively high number of 'positive' findings for anabolic steroids in this study. Although it is considered to be fairly unlikely that the synthesis of these low concentrations of anabolic steroids could lead to a positive doping test, it would be advisable to investigate this risk further.
HACCP - Plus/NZVT system
A total of 38% of the dietary supplements analysed were 'positive'. These 'positive' products came from 57% of the brands. Although many of the low concentrations found could be explained in part by their natural presence in botanical compounds and/or synthesis in phytochemical processes, it is certainly not inconceivable that contamination or cross-contamination may also have played a role. Manufacturers of dietary supplements are therefore advised to continue the critical monitoring of the entire production process and to make
changes where needed in the interest of elite athletes. The use of the risk assessment system HACCP-Plus/NZVT could provide added value in this respect.
