Plasticizers not necessarily evidence of transfusion, says scientist
Alberto Contador during his press conference as he tries to explain how his urine sample became contaminated with clenbuterol (Image credit: AFP)
The World Anti-Doping Agency is prepared to intervene in the doping case of Tour de France champion Alberto Contador should it drag on too long, the agency's general director David Howman indicated today.
Contador tested positive for Clenbuterol in a sample taken during the Tour's second rest day. The Spaniard argued that the substance must have come from contaminated meat, but other sources have alleged that a tainted blood transfusion was the cause. Reports pointed to traces of plastics allegedly detected in the rider's urine as an indication that a transfusion had been taken.
Contador hit back at the allegations last week, calling for an end to such defamatory reports, emphatically denying he had used blood transfusions. There have been no official reports specifying if plasticizers had been detected and at what level.
WADA's scientific director Dr. Oliver Rabin spoke about the charges today, saying, "We can not be 100% sure it was a transfusion, other explanations are possible," for the residues in the sample.
The German laboratory which tested the Tour de France samples reportedly implemented a new test designed to detect autologous transfusions through the presence of chemicals which leech from plastic blood bags into the body during an infusion.
Autologous transfusions are difficult to detect through normal tests and the examination of blood passport values. A former manager to several riders, Stefan Matschiner, revealed this week that even small amounts of a rider's own blood would give a performance boost when re-infused during a Grand Tour.
Rabin said that the test for plasticizers can be used as an indication of possible doping, but said it is not yet validated. "To validate a drug test, it must be confirmed by scientific literature and groups of experts, and it must be usable in all [WADA-accredited] laboratories," he said. "Extensive research is underway involving populations of athletes and samples from the general population, but we can not predict their outcome."
Get The Leadout Newsletter
The latest race content, interviews, features, reviews and expert buying guides, direct to your inbox!
Contador still must face up to the Clenbuterol positive, however. Past cases involving athletes successfully arguing a contaminated food defense have only resulted in a shorter sanction. Howman said that the UCI's investigation is still in its infancy, and that Spain was ultimately responsible for taking disciplinary action if necessary.
Spain previously refused to take action in the case of Alejandro Valverde and other riders named in the Operación Puerto case, allowing the rider to continue to race for years before the UCI successfully pursued his suspension through the Court of Arbitration for Sport.
Howman said WADA was prepared to intervene before Contador's case dragged on, but did not say how long of a delay would prompt action.
