New Clent. Test

[RedheadDane]

Okay, I'll admit that I don't have much of a source here...

But according to this article: http://sporten.tv2.dk/2014-04-24-ny-doping-test-forhindrer-bøf-sager Anti Doping Denmark says that there's a test being developed which can tell whether clent. has been ingested from a primary or a secondary source.
Pleasa, please. Please! Let that be true! These "beef cases" are just plain ridiculous!

 

[Dear Wiggo]

Okay, I'll admit that I don't have much of a source here...

But according to this article: http://sporten.tv2.dk/2014-04-24-ny-doping-test-forhindrer-bøf-sager Anti Doping Denmark says that there's a test being developed which can tell whether clent. has been ingested from a primary or a secondary source.
Pleasa, please. Please! Let that be true! These "beef cases" are just plain ridiculous!

Clenbuterol?

Hopefully they won't let anyone know until it's approved and some urine samples have been retro tested.

Oh wait...

 

[Catwhoorg]

I find it rather hard to believe than clenbuterol is somehow different from a primary or secondary source.

Its not a protein, where subtle structure difference can come into play.

I'd love to hear any more details anyone may have about how they intend for this to differentiate.

 

[RobbieCanuck]

I find it rather hard to believe than clenbuterol is somehow different from a primary or secondary source.

Its not a protein, where subtle structure difference can come into play.

I'd love to hear any more details anyone may have about how they intend for this to differentiate.

If we take Contador as an example, it was my understanding that all of his TDF tests before July 21, 2010 were negative for clen. Then on July 21, 2010 he tests for this miniscule amount of 50 picograms which makes no sense because the amount is so small it could not have had a performance enhancing effect. I understand you need about 200 micrograms for it to have a performance enhancing benefit.

If I understand the argument, he transfuses on July 20, but does not get caught for that on July 21, but the residues of plasticizers indicate a transfusion and the transfused blood is the source of the clen. and this explains the low amount.

Now whether or not this is considered a primary or secondary source of the clen I am not sure.

 

[RedheadDane]

Clenbuterol?

Hopefully they won't let anyone know until it's approved and some urine samples have been retro tested.

Oh wait...

Yes. Clenbuterol, I'm lazy and can't spell (as shown by me thinking the 't' comes right after the 'n'...)

I definitely also hope they don't let anyone know, not as much for retro-testing as for possible future situations.
So, when the test gets fully developed - if it ever does - and someone tries the "I must've eaten some sort of contaminated food!" excuse, then testers can just go "Nice try, buddy, but these test results show that you ingested it from a primary source."

 

[DirtyWorks]

Yes. Clenbuterol, I'm lazy and can't spell (as shown by me thinking the 't' comes right after the 'n'...)

I definitely also hope they don't let anyone know, not as much for retro-testing as for possible future situations.
So, when the test gets fully developed - if it ever does - and someone tries the "I must've eaten some sort of contaminated food!" excuse, then testers can just go "Nice try, buddy, but these test results show that you ingested it from a primary source."

The usual routine is to sanction a minor athlete or three if anything happens.

 

[biokemguy]

metabolites

I find it rather hard to believe than clenbuterol is somehow different from a primary or secondary source.

Its not a protein, where subtle structure difference can come into play.

I'd love to hear any more details anyone may have about how they intend for this to differentiate.

The tests for doping products often detect secondary metabolites of the drug compound rather than the compound directly. Perhaps there's some difference in the levels of these metabolites when a person eats contaminated meat as opposed to using the drug directly.

 

[Dear Wiggo]

The tests for doping products often detect secondary metabolites of the drug compound rather than the compound directly. Perhaps there's some difference in the levels of these metabolites when a person eats contaminated meat as opposed to using the drug directly.

Double digestion vs single?

 

[Merckx index]

This was discussed here before, see my post 415 in the Rogers thread. My post quotes another poster who provided the link to an article documenting the effect, and discusses the article.

Briefly, the test is based on mirror image enantiomers. The two molecules are structurally identical, but mirror images of each other. One of the enantiomers is metabolized faster than the other, hence what is remaining in the body is enriched in the other, slower-metabolized form. Thus CB from an animal injected with the drug has a different ratio of the enantiomers than synthetic CB right out of the lab.

However, there can be a lot of false negatives, because if the animal was injected with CB not long before slaughter, there hasn’t been enough time for a significant change in the enantiomer ratio. I think it has to be about a week.In countries where testing is taken seriously, farmers will allow time for the CB to clear from the system before slaughter, so any CB present in the meat is likely to have a significantly altered ratio. But in places like Mexico and China, it may be that CB is given right up to slaughter, to maximize the effect on the meat.

Edit: Sorry, false positives, i.e., CB in meat from animals killed soon after injection will have properties like CB from the lab. So the test is only good for showing that some athletes definitely got CB from meat, but can't distinguish athletes who doped from those who might have eaten meat from animals with recently injected CB. It's a great test from the athlete's point of view, because it may clear him, but can never show definitively that he took CB intentionally.

 

[HSNHSN]

This was discussed here before, see my post 415 in the Rogers thread. My post quotes another poster who provided the link to an article documenting the effect, and discusses the article.

Briefly, the test is based on mirror image enantiomers. The two molecules are structurally identical, but mirror images of each other. One of the enantiomers is metabolized faster than the other, hence what is remaining in the body is enriched in the other, slower-metabolized form. Thus CB from an animal injected with the drug has a different ratio of the enantiomers than synthetic CB right out of the lab.

However, there can be a lot of false negatives, because if the animal was injected with CB not long before slaughter, there hasn’t been enough time for a significant change in the enantiomer ratio. I think it has to be about a week.

Would it make sense for a farmer to inject a cow with clenbuterol within the last week before slaughter anyway? I don't quite know how fast the substance works, but it sounds like it would be of more use earlier on. In which case the last remark wouldn't really be a problem.

 

[Catwhoorg]

This was discussed here before, see my post 415 in the Rogers thread. My post quotes another poster who provided the link to an article documenting the effect, and discusses the article.

Briefly, the test is based on mirror image enantiomers. The two molecules are structurally identical, but mirror images of each other. One of the enantiomers is metabolized faster than the other, hence what is remaining in the body is enriched in the other, slower-metabolized form. Thus CB from an animal injected with the drug has a different ratio of the enantiomers than synthetic CB right out of the lab.

However, there can be a lot of false negatives, because if the animal was injected with CB not long before slaughter, there hasn’t been enough time for a significant change in the enantiomer ratio. I think it has to be about a week.In countries where testing is taken seriously, farmers will allow time for the CB to clear from the system before slaughter, so any CB present in the meat is likely to have a significantly altered ratio. But in places like Mexico and China, it may be that CB is given right up to slaughter, to maximize the effect on the meat.

Edit: Sorry, false positives, i.e., CB in meat from animals killed soon after injection will have properties like CB from the lab. So the test is only good for showing that some athletes definitely got CB from meat, but can't distinguish athletes who doped from those who might have eaten meat from animals with recently injected CB. It's a great test from the athlete's point of view, because it may clear him, but can never show definitively that he took CB intentionally.

Thank you,
That makes sense.