Food Contamination

Consumption of meat in Mexico, China or Guatemala may lead to unintentional ingestion of the prohibited substance clenbuterol. Federations and athletes should take appropriate precautions.


  • When travelling to Mexico, China and Guatemala, special precautions must be taken when eating meat.
  • The need in proteins should be covered by a variety of sources in smaller portions. For example, meat from various animals, fish, tofu or dairy products. There is no information on contamination of dairy products by clenbuterol.
  • Shakes or bars can be considered for higher protein needs. The need should be clarified with a specialist. Certified products or those from trustworthy Swiss manufacturers with a clear reference to competitive sports should be favored.
  • At competitions, the official catering facilities should be used.
  • If possible, the meals should be taken in groups and not individually.
  • Ideally, the places and the food hat was eaten should be documented (photos, receipts).

What is Clenbuterol?

  • Medical purpose: Active ingredient for the treatment of asthma (not approved in Switzerland)
  • Side effects: Increased heart rate, high blood pressure, tremors, headache, nausea, agitation
  • Prohibited List: Prohibited substance at all times under Class S1.2 "Other Anabolic Agents"
  • Use in sports: As doping (anabolic effect)
  • Use in animal fattening: To increase production (prohibited in most countries)
  • Countries from which information on contaminated meat is available: Mexico, China and Guatemala

Samples during or after trips abroad

On June 1, 2019, a new WADA regulation came into force. If only traces (<5ng/ml) of clenbuterol are detected during the analysis of a sample in the laboratory, it will be considered an Atypical Finding (instead of an Adverse Analytical Finding). If the athletes concerned can then credibly prove that clenbuterol entered their bodies during their stays in Mexico, China or Guatemala through the consumption of contaminated meat, generally this does not result in a suspension. If, however, Antidoping Switzerland concludes, after a foreseen investigation, that the Atypical Finding cannot be justified by meat contamination, an anti-doping rule violation is claimed and the usual disciplinary proceedings are initiated. If ≥5ng/ml clenbuterol is detected in a sample, this is still considered a positive result, which will lead to disciplinary proceedings accordingly.

Antidoping Switzerland therefore recommends that athletes continue to comply with all the above recommendations after 1 June 2019.