As the tension rises over the potential different outcomes to Alberto Contador’s positive for clenbuterol, Peter Van Eenoo, the head of WADA’s only accredited anti-doping lab in Belgium at the University of Ghent, has discussed the ins and outs of testing for the banned substance with Cycling Weekly.

Van Eenoo refused to discuss specific cases, although his laboratory was reportedly the one which discovered Chinese rider Fiyu Li’s positive for clenbuterol this spring.

(Cycling Weekly) CW: How does testing for clenbuterol work?

(Peter Van Eenoo) PVE: Through a combined detection method called GC-MS. Part of the process is gas chromatography [GC], which separates different elements, and the other part, mass spectrometry [MS], identifies them.

CW: Any major advances in the last few years on this process?

PVE: Not over the last two decades or so. Just that the instruments which we used have got a lot more sensitive. We’re getting better at detecting it.

CW: Although there have been reports that only four labs in the world could have detected the levels found recently in Alberto Contador’s urine…

PVE: That story can only be completely made up. Each WADA lab only knows their own results from tests, and although we do talk to each other, we don’t know where the other results have come from, they’re completely anonymous. I don’t see how anybody can have said that.

CW: Could a positive for clenbuterol come from other causes than direct doping?

PVE: It’s possible. Contaminated products or foodstuffs are possible causes too. But in my opinion, you have to bear in mind whether it’s the first athlete or athlete number 10,000 who alleges a clenbuterol positive has been caused by a particular contaminated product.

An athlete is always responsible for what is in his body fluids. If there’s a positive but there’s a reason for a reduction in the suspension, like food contamination, then he or she will have his sentence reduced.

CW: Why is there no limit of detection (tolerance level) when testing for clenbuterol?

PVE: Because its effect is long-term and spread out, and there’s no clear correlation between the clenbuterol an athlete takes and the effect it has. On top of that, clenbuterol only breaks down in the body very slowly.

So if I took a lot and you and tested me an hour later, I might have a lot left in my system.

But if you tested me in four or five days, it might still be there. Either way you wouldn’t know what effect it had had. That’s why clenbuterol is always a positive.

Related links



Contador considers quitting cycling due to doping scandal

  • Z Liu

    I am not a perfessional cyclist, but I am a chinese citizen who lived in china for two year from 25-26 year old. After the first year, I start to notice fat lose and getting slimmer no matter how much I eat( I eat a lot various food and meat and doin short regular exercises like fast cycling to work and go home every day for 40 minute) .

    I sometimes have muscle minor muscle twitch on my thigh and arm.

    after about two whole year, During 1st oct 2011(a day of 7-day national holiday) I eat a lot boiled lamb (like 1kg) in a meal. Them after 7 days, I start getting palpitations very often at night before a late night go-to-bed). and since then, every before late night sleep or getting up earlier for a while, I get 4-5 palpitaitons every five-minute. a ECG shows sinus arrhythmia for a early get up and do the test. Recently, ECG after a good sleep is normal。 I have no problem with strength and I am very energetic, I always doing things faster than normal people, walk faster etc.

    I noticed that china farmer has long been using clenbuterol for there pig、sheep、not sure cow or any other livestock。and the government forbidden strength is weak, there is still people using clen even now. After I read the side effect and residues of this drug last long. I suspect that my body has accumulated certain amount of Clenbuterol during the last two years, which cause my symptoms above. In china’s class 3 hospital, they said they have no equipment for testing human clenbuterol, so i just write this here to inform Cyclist who live in China for long term.

  • Eric Kwiatkowski

    I’d be interested to know what levels of Clenbuterol are detected in the population at large.

  • Oracle

    AJ, you obviously missed this article then…

    http://www.cyclingweekly.co.uk/news/latest/501965/alberto-contador-the-clenbuterol-the-beef-excuse-and-the-traces-of-plastic.html

    Still, don’t let that cloud your judgement.

  • AJ

    CW’s search to clear AC continues– —no questions about plasticisers from stored blood, for obvious reasons

  • steve

    The points you raise regarding the substance not being found in previous samples are as damning if not more due to
    blood transfusion theory which seems to become more and more credible as time goes on!

  • John Calliott

    I really hate that interview for a couple of reasons. The five day thing is nonsense, as there were no traces of Clenbuterol the day before the positive. Addressing only that positive, and the smaller one the next day, does not rule out the possibility of ingesting something tainted. His statement makes a bit more sense for athletes who are rarely tested, but Contador was in a position to be tested every day. The comments should have addressed that. And the concept that an athlete needs to know the origin and history of every bit of food or drink they consume has nothing to do with a life where training includes stops for coffee and replenishment, or guys spends weeks at training camps or doing recon away from home. WADA and the labs are trying to cover their decisions after causing lesser known athletes to suffer in the past. I’m 100% against doping, & probably ignoring pro cycling after this, but life isn’t as controlled as people in labs assume.