Chickengate

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In 2011 Mexico were preparing for the Gold Cup, the biennial CONCAF Championship featuring countries from North America, Central America, and the Caribbean.

However, on the eve of the tournament, five players, including first-choice goalkeeper Guillermo Ochoa and defender Francisco Rodriguez, tested positive for the banned substance clenbuterol an anabolic agent commonly used by bodybuilders and celebrities to help them lose weight, and as a treatment of eating disorders..

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The five – the others including fringe players defender Edgar Duenas, and midfielders Antonio Naelson “Sinha” and Christian Bermudez – were all found guilty and were banned from the tournament.

Despite this their defence, which was supported by the Mexican football federation, was that they had ingested the food in contaminated meat, such as chicken or beef. Clenbuterol is also used as a growth hormone in the animal rearing and processing industries, helping to speed up development and increase muscle mass.

A similar defence was mounted by Tour de France champion Alberto Contador, who also tested positive for the banned substance.

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In 2010 he  tested positive for it during the race and, after a long court battle, he was eventually suspended by the Court of Arbitration for Sport (CAS) and banned for two years.  CAS eventually rejected his assertion that he had ingested contaminated meat.

Similarly, two Australian Rules Footballers, Lachie Keeffe and Josh Thomas received similar bans after testing positive for the drug. In their case their defence was undermined by admitting that the substance probably got into their system whilst they had been taking other illicit drugs.

In the case of Mexico though, there was no immediate lasting harm. Despite the five being dropped from the squad, they still went on the win the tournament, beating the USA in the final which was played in Pasadena.

That same year, Mexico played hosts to the under-17 World Cup, going on to win the tournament for the second time in their history. Yet again, four Mexican players were found to have clenbuterol in their system, prompting FIFA to launch an investigation.

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That found that a majority of the players tested had traces of the substance in their system. Tests in Germany after the tournament found that players from 19 of the 24 teams taking part had traces of it.

In most cases, the levels of clenbuterol found in the players’ systems was higher than that when Contador was tested.

Mexico later admitted that it had issued with feeding banned steroids to livestock. Subsequently, a number of farmers were arrested and slaughterhouses shut down.

FIFA decided that, on the basis of the evidence, it was not a problem of doping, but a public health issue, and that indeed it was down to eating contaminated meat.

Noe of the players who tested positive on that occasion were found guilty and banned.

The original five, though, have never had their names cleared.