This study, about five years old, analyzed about 50 samples of different supplements, and found that about 25% were contaminated with steroids, and about 10% contaminated with stimulants (CB is classified as a stimulant). What I found very interesting was not the number of samples that didn’t pass inspection (earlier studies have come to a similar conclusion), but that the detection limit used for CB and other stimulants was 100 ng/g.* The level used for meat in Europe is a thousand-fold lower—100 ng/kg—which means that “clean” supplements can be considerably more contaminated than clean meat. This is basically what opens the door to an appeal (assuming it can be done within the legally allowed framework).
I hadn’t known this before (I have never taken supplements), but most of these supplements are ingested in multi-gram quantities, even the pills or tablets, let alone the drinks, powders, power bars, etc. (See note* below, the detection limit is based on ingestion of 50g. daily of the supplement). So a supplement that tested clean could still have an amount of CB that could result in a positive test in Cologne. Specifically, it has been estimated that Bert’s 50 pg/ml urine concentration would correspond to an ingestion of 200-500 ng of CB. One can modify assumptions and widen that range, but the bottom line is that it is extremely likely—certainly far more than balance of probabilities-- that IF Bert’s positive resulted from ingesting a supplement of several grams or more, that supplement would have tested clean by what is at the very least a recent industry standard. So if CAS wants to make the official cause of the positive a contaminated supplement, they are forced to concede that there is nothing Bert could have done to avoid that contamination. He is not at any fault whatsoever.
In fact, WADA has already laid the groundwork for this rationale. At RFEC, WADA argued on the basis of pharmacokinetics that Bert’s level of CB could not be explained by meat that passed the Euro criterion. This argument is entirely correct, and was accepted by Bert's team, but by making it, WADA is acknowledging that if Bert had a lower level (say 5-10 pg/ml), his positive could have resulted from meat that passed inspection, and that therefore he would have not been at any fault. If a contaminated supplement was the source of the CB, Bert is no more at fault for ingesting it than he would be for a lower level of CB that resulted from eating Spanish meat that passed inspection. In either case, the athlete cannot be held responsible for consumption of something that passes the official standards.
I’m not pointing this out because I think Bert is necessarily innocent of doping. The positive DEHP test, for me, is very compelling evidence of transfusion. I think it’s quite possible he transfused blood without CB, and also took a contaminated supplement, the latter being what triggered the positive. But legally, the DEHP positive doesn’t carry much weight. It’s all about CB. And I think CAS has set a trap for itself here. To reiterate, there is basically no way this amount of CB could have gotten into Bert's system from a contaminated supplement unless that supplement passed the industry standard. If the supplement was contaminated at a level that would make the athlete responsible, Bert's urine level would have tested at a considerably higher level.
I don't know if Bert can appeal on this basis. Supposedly one can appeal only on the basis of procedural errors. But this is complex, because Bert would not be appealing the decision itself, only the sanction associated with that decision. Technically, I don't know if this would be considered a procedural issue or not, maybe a legal mind would know.
Unlike the case with meat, there are no legal implications for supplements failing to meet some standard. They are unregulated, at least in the U.S. (don't know about Spain, but thanks to the internet, they are a global product, anyway). But I don't think this should matter in a doping case. If laboratories testing substances for contamination can't or don't detect the contaminant below a certain level, how can you possibly blame the athlete? If an athlete can be banned on this basis, UCI/WADA should institute a blanket prohibition of all supplements whatsoever, because there is no guaranteed way to protect oneself.
The only argument against the actual logic of this appeal I can see is the reported blood level of CB for Bert that was mentioned in the CAS report (the initial positive, to make sure everyone is clear on this, was based on a urine test; after preparation for the CAS appeal got under way, WADA apparently tested for CB a blood passport sample that Bert provided about the same time during the Tour). But that level, 1 ug/ml, has to be wrong. I'm quite sure no one in recorded history has ever had a CB level that high, and even if it were possible without killing yourself, you certainly couldn't get it from transfusing a few hundred ml of contaminated blood. They may have meant 1 ug/l, or 1 ng/ml, but that level still is not consistent with a urine level of 50 pg/ml about twelve hours later, nor is it consistent with any kind of transfusion scenario. It would also be pretty unlikely to result from a contaminated supplement, though it would be possible. But the initially reported urine levels, 50 pg/ml on 7/21 followed by values in the 5-20 pg/ml range on three succeeding days, are all consistent with each other, and it would be extremely difficult IMO to argue that some other, much higher, value during that same time period was valid.
*The rationale for this detection limit:
Based on the published facts that a precursor of an anabolic steroid in an amount between 1–10 μg can cause a positive doping test,18,24 and based on the fact that athletes easily use 50 g of supplements per day or more, a reporting threshold value of 10 ng/g or 10 ppb for all anabolic steroids is used in all tests. This value also allows for individual variations in metabolism. Excretion studies for stimulants are rare, but similar considerations led to the conclusion that for stimulants, a reporting threshold value of 100 ppb is opportune.
Olivier de Hon and Bart Coumans The continuing story of nutritional supplements and doping infractions Br J Sports Med. 2007 November; 41(11)
Clearly, these detection limits were based on the much lower sensitivity of detection for substances such as CB prior to introduction of the more advanced equipment used at Cologne.