01/12/2009, COLOGNE - Basketball players have to be very careful in using nutritional supplements that can be purchased on the market without restrictions or medical prescriptions. Those supplements could be cross-contaminated and faked with doping substances.

In 1999, in connection with follow up studies of positive doping cases with norandrosterone, we detected the first cases of nutritional supplements cross-contaminanted with anabolic-androgenic-steroids (prohormones).

Our international study performed in 2001 and 2002 on 624 nutritional supplements purchased in 13 different countries showed that about 15 percent of non-hormonal nutritional supplements contained anabolic-androgenic steroids (mainly prohormones) not declared on the label.

Since 2003 we have detected also products intentionally faked with high amounts of “classic” anabolic steroids as metandienone, stanozolol, boldenone, dehydrochloromethyltestosterone, oxandrolone etc. on the nutritional supplement market. These anabolic steroids were not declared on the labels too.

The sources of these anabolic steroids are probably Chinese pharmaceutical companies which sell bulk material of anabolic steroids.

At the end of 2005, German food control services confiscated nutritional supplements faked with high amounts of metandienone and stanozolol from a German manufacturer.

The analyses of vitamine C -, multivitamine - and magnesium – tablets, which were produced from the same manufacturer on the same production line within the same time interval showed cross-contaminations of these products with metandienone and stanozolol. These vitamine C -, multivitamine - and magnesium-tablets were sold in ordinary German and Spanish groceries and drug stores.

Since 2005 new “designer” steroids such as prostanozol, 6-bromo-androstenedione, 17-methyl-drostanolone etc. are offered on the nutritional supplement market.

In nutritional supplements for weight loss we detected in the last two years stimulants like sibutramine and methylhexaneamine and the ß2.agonist clenbuterol. All these doping substances were not or only nebulously declared on the label.

Based on these results we can conclude that the situation on the nutritional supplement market has become worse and the risk of inadvertent doping cases has increased.

In order to assist athletes and to reduce the risk we have published the Cologne List that can be found here: www.colognelist.com

Dr. Hans Geyer
Institute of Biochemistry and Center for Preventive Doping Research, German Sport University Cologne

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