Alberto Contador is the elite cyclist and 2010 Tour De France winner who failed a test for clenbuterol, and his case is still being litigated with seemingly endless delays. Contador's lawyers have claimed that the clenbuterol came from an imported steak brought into France by a buddy that he ate coming from a cow that has allegedly been illegally injected with the substance. (I previously wrote about this case here.)
If that were true, poor Contador is the unluckiest athlete in the world.
The case is supposedly coming to an end although it has dragged on and on. We were told recently that his defense may be boosted by a situation that happened in Mexico this year.
In the Under-17 World Cup tournament, held earlier in Mexico, 109 out of 208 samples collected from players tested positive for clenbuterol! The anti-loping labs have decided not to prosecute these cases because Mexican farmers have been known to use clenbuterol, and all these athletes may have been victims of food "poisoning".
According to the "conventional wisdom" such as this, the Mexican situation should bolster Contador's case. It shows that Contador's explanation is credible.
On the contrary, this situation actually makes the anti-doping labs look good.
First, it shows the effectiveness of the test for clenbuterol. The test performs as expected. It detects the substance.
Second, what happens in Mexico does not translate to Europe. If it did, then we should have seen half of the athletes in the Tour De France failing the test but that didn't happen. Not even close. In addition, we know that European farmers are banned from using clenbuterol and in 2008-9, only one out of 83,000 samples tested positive for it. (That's why Contador must be extremely unfortunate if his story were indeed true.)
As I concluded in Chapter 4 of Numbers Rule Your World, it's not the job of anti-doping labs to do lie detection - their job is to do chemistry. There is no argument that clenbuterol was found in his sample. The debate is over how the clenbuterol got therel; that debate can almost never be settled by a lab test. We need a powerful polygraph but we don't have one.
If Contador's positive result is upheld, there is a small chance that he would have been falsely accused. But in my view, the anti-doping world needs more false positives, not fewer. See my previous post here.