WADA withdraws clenbuterol appeals against Mexican footballers & Danish cyclist

World Anti Doping Agency (WADA) has called off two appeals to the Court for Arbitration in Sport (CAS) over the decisions by Mexican Footabll authorities and the Danish Cycling Federation to acquit in two high profile cases involving failed tests for the doping agent, clenbuterol.

The Mexican case involved five players from the national team testing positive for clenbuterol during last year's Central American Football championships – they claimed to have eaten tainted meat during a training camp before the tournament started.

Mexican beef was also the common denominator in the case of Danish cyclist Philip Nielsen who failed a test for clenbuterol at the Vuelta a Mexico last year. Mexico is widely acknowledged to have a wide-spread problem with  livestock farmers illegally using clenbuterol and steroids on their cattle and the resulting contaminated meat. In both cases the relevant governing bodies backed the athletes and rescinded their bans resulting in WADA's appeal to CAS to have them re-imposed.

However the Mexican FA were backed up in their stance by FIFA and WADA was yesterday forced to back down after the world football body produced a dossier of what a WADA in a statement published on its website acknowledged to be "compelling evidence" compiled by FIFA and the Mexican Government at the U17 World Cup in Mexico "that indicates a serious health problem in Mexico with regards to meat contaminated with clenbuterol. This is a public health issue that is now being addressed urgently by the Mexican Government."

As a result WADA will not now proceed with the two appeals instead the organisation has issued a warning to athletes competing in the upcoming Pan American Games in the Mexican state of Guatalajara to only eat in cafeterias designated as safe by the games organisers and wherever possible to eat in large numbers. The study in to Mexico's clenbuterol problem will now become a joint one between WADA, FIFA and the Mexican Government.

Next month WADA and the UCI will be back in court to argue their case in the most high profile clenbuterol doping case of them all – that of 2010 Tour de France 'winner'* Alberto Contador. The UCI and WADA are appealing against the decision of the Spanish Cycling Federation (RFEC) to throw out the case against Alberto Contador who tested positive for clenbuterol following a rest day doping control during the 2010 Tour. Contador has always maintained that he ate a contaminated steak brought over the border for him by a friend.

While yesterday's developments further underline the possibility that accidental ingestion of clenbuterol can occur and can lead to a failed test, WADA is sticking to its stance that clenbuterol is a prohibited substance and that it will treat each individual case on its merits. The organisation has resolutely refused to set a minimum threshold for the substance as recently as last month re-confirming it's zero tolerance approach.

In Contador's case WADA acknowledges that while accidental ingestion of clenbuterol can occur in countries where the practice of dosing cattle with the substance is widespread that problem is currently limited to Mexico and China and the Spanish livestock industry has no such record of clenbuterol contamination so this cannot be used as a mitigating circumstance by the Spanish rider.

*The quote marks can come off when the court rules who won