The German-based Nationale Anti-Doping Agentur (NADA) is warning footballers against the dangers of unintentional doping with the prohibited substance Clenbuterol.
The warning has particular significance for young European players who will be travelling with their national teams to the FIFA U-17 World Cup in Mexico from 18 June to 10 July this year.
NADA has reported that the problem of Clenbuterol-contaminated food seems to be expanding, and that a recent study of the Manfred Donike Institute and the Centre for Preventive Doping Research at the German Sport University of Cologne highlights an increased risk of unintentional doping with Clenbuterol in Mexico. China is also said by NADA to have a similar situation.
"NADA Germany therefore recommends, similarly to travelling to China, to be highly cautious with victuals in these countries," the organisation says. "The study report shows significantly increased values in the urine samples of two travellers who returned in March 2011 after a three-day trip to Mexico. The urine samples were taken on the first day after their return.
"The concentrations of Clenbuterol were around 115pg/ml and 90pg/ml. Urine samples taken before the trip to Mexico were Clenbuterol-free. These values were even higher than samples analysed of travellers from China, which had led to a warning by the laboratory in Cologne and NADA Germany in mid-February.
"So far, there is no threshold-level for Clenbuterol in the anti-doping-regulations: thus, the concentrations found in the study would result in an adverse analytical finding. As a general rule, athletes are responsible for themselves and should be extremely cautious about any substances which could cause a positive result.
"NADA Germany recommends particular vigilance with food when travelling to Mexico or China. As far as possible the consumption of meat products should be omitted. For proposals on alternative protein sources other than meat, please refer to the nutritionists of the Olympic Training Centres, in accordance with the German Olympic Sports Confederation recommendation."
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