Impey cleared of doping - free to race

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From the VN link:

Impey’s defense focused on a pharmacy in Durban, on the country’s eastern coast. A report in The Star newspaper explained that the pharmacist gave Probenecid to another customer and sold Impey empty gel capsules with contaminated hands. The Durban pharmacist took the blame and produced cash register receipts showing the times of the purchases.

How did the contaminated hands version ever get out, if it was the pill counter? If Impey got expert testimony that actually proved that the amount of possible contamination was consistent with the level he tested for, it would have been based on analysis of the pill counter. That being the case, why wouldn’t the pill counter story have been firmly established from the very beginning? Why would the contaminated hands version ever see the light of day?

Might be sloppy reporting, but seems a little strange that the journalists couldn't get their facts straight. Were they not initially told the source of contamination, and just assumed it was the hands? Would like to hear one of the journos explain why they initially reported the story in this manner.

We presented the hearing with hard facts, factual proof. This was no ‘maybe’ or ‘could have been.’”

Well, no, this is not correct, it is "could have been". He might have demonstrated that his tested level could have resulted from contamination, that the level of possible contamination could have resulted in the detected level, but this is not factual proof. Factual proof in a case like this would require showing that the prob in his body actually originated from that pharmacy, and that he never purchased prob itself from that pharmacy. That is not possible, no analysis can determine where the prob came from.

I’m not saying that he doesn’t have a good case, he might well have when we finally see the analysis. But a winning case in this situation can't be based on factual proof. At best, he can show that contamination could account for his test results. Or possibly, that use of the pill counter always results in this level of contamination, that anyone purchasing capsules right after the counter was used for prob would have had the capsules contaminated to the level needed.

But I think this would be very hard to establish. Contamination is something that will vary from incident to incident, no scientific analysis can determine how much contamination occurred in a particular incident. Maybe they determined a minimum level that they felt would always result from the pill counter, but this seems dubious to me. That would require a carefully controlled study. I doubt they did this, but we will see, or not.

Again, the Contador case is instructive. Factual proof would be having a meat sample from an actual dinner, and witness testimony that he ate that meat. He didn't have that kind of proof, and sought to show that meat contamination was possible. He couldn't establish that, either, but athletes in other countries could at least demonstrate that contaminated meat was possible. They got off not because of factual proof, but because they were able to make a reasonable case for possibility. That is almost certainly what Impey did here.
 
Parker said:
If this is the case then two questions present themselves:

a) why did he buy the probenecid and the capsules two hours apart
b) if the bicarbonate of soda was to ameliorate the probenecid, why did he need the capsules. A spoon gets the job done.

Agree. I don't believe in the one person theory. I find more likely that an accomplice bought probenecid two hours before Impey got the capsule to make possible the cross-contamination defense in the event that Impey got caught. Also, the bicarbonate of soda allegation may be getting too much of our attention. Maybe it was just the first thing that came to Impey's mind. I don't believe anyone would play pharmacist, waste time and money to make bicarbonate of soda pills: a spoon gets the job done as you wrote...
 
Granville57 said:
How about we give this some more attention?

Wiki has Impey listed at 70kg.

Everything I've read indicates that recommended dosages of sodium bicarbonate would be 200-300mg per kg of body weight.

Even on the low end of that scale, that would mean 14 grams, or about one tablespoon of powder.

Based on common empty capsule sizing, it's my understanding that that would equate to roughly 20 to 25 caps, depending on the individual size of the capsule. This would obviously increase to 30 or more caps if using the 300mg/kg ratio.

That would be one helluva lot of pill popping, no?
Does this make any sense?

My numbers may be wrong, but if not, I would love for Impey to publicly state exactly what his proven methods in the past have been regarding the use of sodium bicarbonate.

How much does he usually take?
How long before an event?
Over what period of time?

This isn't EPO we're talking about, so should there really be any great trade secrets behind its consumption?

I just find the method of delivery in this case to be somewhat questionable.


Some references:
http://www.bodybuilding.com/fun/soda-for-sprints-sodium-bicarb-as-a-supplement.html
http://convert-to.com/753/baking-powder-conversion-plus-nutritional-facts.html
http://www.capsuleconnection.com/capsules

yes, it would be quite a lot of capsules to hit .3g/kg. He may have been using serial loading[1], i.e. spreading the dosage out over the course of a day. Sodium bicarbonate is high in sodium, is it possible to use it as a homemade electrolyte capsule? Nuun uses it in their tabs[2]. Nuun/hammer/etc. are silly expensive relative to their relatively run-of-the-mill ingredients. Even if Impey wanted to use it purely for the acid-buffering effect, it would make sense to increase the portability to the point you could take some along with you on the bike. His 7 minute maximal effort comes at the end of 4-6hrs of riding, so loading beforehand might be less effective.

[1] http://www.ncbi.nlm.nih.gov/pubmed/23001395
[2] http://www.nuun.com/products
 
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Tonton said:
Agree. I don't believe in the one person theory. I find more likely that an accomplice bought probenecid two hours before Impey got the capsule to make possible the cross-contamination defense in the event that Impey got caught. Also, the bicarbonate of soda allegation may be getting too much of our attention. Maybe it was just the first thing that came to Impey's mind. I don't believe anyone would play pharmacist, waste time and money to make bicarbonate of soda pills: a spoon gets the job done as you wrote...

So.....what were the capsules for?
 
Jul 11, 2013
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Merckx index said:
From the VN link:



How did the contaminated hands version ever get out, if it was the pill counter? If Impey got expert testimony that actually proved that the amount of possible contamination was consistent with the level he tested for, it would have been based on analysis of the pill counter. That being the case, why wouldn’t the pill counter story have been firmly established from the very beginning? Why would the contaminated hands version ever see the light of day?

Might be sloppy reporting, but seems a little strange that the journalists couldn't get their facts straight. Were they not initially told the source of contamination, and just assumed it was the hands? Would like to hear one of the journos explain why they initially reported the story in this manner.



Well, no, this is not correct, it is "could have been". He might have demonstrated that his tested level could have resulted from contamination, that the level of possible contamination could have resulted in the detected level, but this is not factual proof. Factual proof in a case like this would require showing that the prob in his body actually originated from that pharmacy, and that he never purchased prob itself from that pharmacy. That is not possible, no analysis can determine where the prob came from.

I’m not saying that he doesn’t have a good case, he might well have when we finally see the analysis. But a winning case in this situation can't be based on factual proof. At best, he can show that contamination could account for his test results. Or possibly, that use of the pill counter always results in this level of contamination, that anyone purchasing capsules right after the counter was used for prob would have had the capsules contaminated to the level needed.

But I think this would be very hard to establish. Contamination is something that will vary from incident to incident, no scientific analysis can determine how much contamination occurred in a particular incident. Maybe they determined a minimum level that they felt would always result from the pill counter, but this seems dubious to me. That would require a carefully controlled study. I doubt they did this, but we will see, or not.

Again, the Contador case is instructive. Factual proof would be having a meat sample from an actual dinner, and witness testimony that he ate that meat. He didn't have that kind of proof, and sought to show that meat contamination was possible. He couldn't establish that, either, but athletes in other countries could at least demonstrate that contaminated meat was possible. They got off not because of factual proof, but because they were able to make a reasonable case for possibility. That is almost certainly what Impey did here.

Re Contador and the comparison:
http://epublications.bond.edu.au/cgi/viewcontent.cgi?article=1015&context=slej

In the appeal, the UCI and WADA argued that Contador had failed to meet the burden of proof
of establishing the means by which the substance entered his system. The rules provide that it is
for the athlete to establish how the substance came to be in his or her system.
This requires proof on the standard of balance of probabilities. The CAS panel stated that the athlete’s burden could not reasonably be higher than that (as is the case with the prosecution, who are required to
establish the commission of an anti-doping violation on the standard of ‘comfortable satisfaction’
)

If this is correct, Proof is on the balance of standard of probabilties...
They may have receipts, credit card details, video surveillance, eye witnesses confirrming that the buy of PB took place two hours before and that the same pill-counter was used...


Furthermore

In Contador, however,
the athlete attempted[/B] to raise a number of alternative explanations for the
presence of Clenbuterol in his sample. The CAS Panel stated that:
…if, after carefully assessing all the alternative scenarios invoked by one of the parties as to the
source of entry of the Prohibited Substance into the Athlete’s system, several of the alleged sources are deemed possible, they have to be weighed against one another to determine whether, on balance, the more likely source is the one invoked by the Athlete. However, in the extreme
situation that multiple theories were held to be equally probable, the burden of proof, i.e., the risk
that a certain fact upon which a party relies cannot be established, would rest with the Athlete.

My point is that I do not think you can compare the two cases without taking into account the above...

It seems that SAID deemed the evidence suggesting Impeys single explanation as valid...

UCI and eventually CAS would might have deemed otherwise..

I'am looking forward to more facts released in this case..
 
Dec 11, 2013
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http://www.pponline.co.uk/encyc/soda-loading.htm

The generally accepted protocol for bicarbonate loading is to divide the calculated total dose into five relatively even amounts and, starting three hours before competition, to stagger the intake at 30-minute intervals so that loading is complete an hour before the start.

So 70kg athlete say a 15g dose

3g every half hour
6 500mg capsules.

Doesn't seem unreasonable


Athletes have been practising ‘soda loading’ or ‘bicarbonate loading’ for over 70 years in an attempt to delay the onset of muscular fatigue during prolonged anaerobic exercise.
 
Tonton said:
Agree. I don't believe in the one person theory. I find more likely that an accomplice bought probenecid two hours before Impey got the capsule to make possible the cross-contamination defense in the event that Impey got caught....

oh come on !

Impey has sat with his lawyer and they,ve come up with the capsule theory. A chemist in Durban would take a nice payment for colaborating his story and hey presto. Its probably in the legal casebook as possible defences.
 
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Tonton said:
Agree. I don't believe in the one person theory. I find more likely that an accomplice bought probenecid two hours before Impey got the capsule to make possible the cross-contamination defense in the event that Impey got caught. Also, the bicarbonate of soda allegation may be getting too much of our attention. Maybe it was just the first thing that came to Impey's mind. I don't believe anyone would play pharmacist, waste time and money to make bicarbonate of soda pills: a spoon gets the job done as you wrote...

If he is/was that clever. It would mean that he would also be certain that The Independent Anti Doping Tribunal would accept this as "outside" strict liability...

To prove it possible is not enough.. You have to prove it more likely than doping... So are you saying that Impey has local phamacists and the national anti-doping agency in his pocket.. Let alone the issue of appeals he might face in CAS? All this for using a masking-agent which has been easily detectable for many years?

Balance of probabilities....
 
Jul 11, 2013
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DirtyWorks said:
I not so sure the UCI will appeal. Stranger things have happened.

If they appeal and eventually lose, well it could be dangerous..
Thinking about it, I tend to agree.. Better leave this one alone..
We'll see...
 
mrhender said:
If he is/was that clever. It would mean that he would also be certain that The Independent Anti Doping Tribunal would accept this as "outside" strict liability...

To prove it possible is not enough.. You have to prove it more likely than doping... So are you saying that Impey has local phamacists and the national anti-doping agency in his pocket.. Let alone the issue of appeals he might face in CAS? All this for using a masking-agent which has been easily detectable for many years?

Balance of probabilities....

No. But I wonder if someone smart could send an accomplice buy some of the PED just before the someone goes to the pharmacy to get a prescription, hence making the cross-contamination defense possible if caught.
 
Tonton said:
No. But I wonder if someone smart could send an accomplice buy some of the PED just before the someone goes to the pharmacy to get a prescription, hence making the cross-contamination defense possible if caught.

Why would someone with this detailed level of planning and foresight just not stop taking the drug in good time before a race where he was near certain to be tested? It's like an F1 team Covering every detail and then turning up at the wrong track. He's managed several years without testing positive, so why the complex plot all of a sudden.
 
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proffate said:
yes, it would be quite a lot of capsules to hit .3g/kg. He may have been using serial loading[1], i.e. spreading the dosage out over the course of a day. Sodium bicarbonate is high in sodium, is it possible to use it as a homemade electrolyte capsule? Nuun uses it in their tabs[2]. Nuun/hammer/etc. are silly expensive relative to their relatively run-of-the-mill ingredients. Even if Impey wanted to use it purely for the acid-buffering effect, it would make sense to increase the portability to the point you could take some along with you on the bike. His 7 minute maximal effort comes at the end of 4-6hrs of riding, so loading beforehand might be less effective.

[1] http://www.ncbi.nlm.nih.gov/pubmed/23001395
[2] http://www.nuun.com/products

He tested positive the day of the TT (Feb. 6). He was also tested Feb. 8 (no race) and Feb. 9 (road race), but the tests "yielded no adverse results".

He might have been taking his homefilled gelatine capsules all these days, but only the one/ones he took on the day of the TT was contaminated? Or did he only take them for the TT, or prior to the South African Championships so that the probenecid was out of his system by the 8.

http://www.darylimpey.com/News/DisplayNewsItem.aspx?niid=34129

The sodium bicarbonate in the Nuun tablets might be there to make them fizzy when put into water, to better disolve.

Some have made a point of him not declairing the capsules on the doping test form. But do we know that as a fact?
 
Parker said:
Why would someone with this detailed level of planning and foresight just not stop taking the drug in good time before a race where he was near certain to be tested? It's like an F1 team Covering every detail and then turning up at the wrong track. He's managed several years without testing positive, so why the complex plot all of a sudden.

That's why I want to know that the investigation went in depth, to make sure that the pharmacist is not in it, including looking at the customers of this particular pharmacy to ensure that he's not the South African Dr. Mabuse, check that the customer before Impey is in no way acquainted to him, see if there are leftover capsules, how they test... and not the least, get some credible answer as to why Impey is buying capsules: is he playing pharmacist in his basement (or elsewhere)? To manufacture what? I find that quite suspicious.

The plot would be an interesting way to make the old "someone must have tempered with my bottle" excuse stand. That's what really interests me in this case.
 
Merckx index said:
This is very interesting. If he really did consult pharmacokinetic experts, then he didn't just claim the powder could have contaminated the capsules, but provided an estimate of how much contamination was possible, and showed that this was consistent with the level he tested for. As I said before, I didn't think he could get such analysis and testimony done in the time since the end of June, but looks as though he did. I will be very interested to see the numbers.

Wrt NaHCO3, you don't ingest it in baked products, because during the baking process it breaks down and releases C02. That's the whole point of using it. However, I agree that it isn't or shouldn't be classified as a supplement, as sodium, bicarbonate and carbonate ions all exist naturally in the body.

I guess you could have an argument, though. Doping frequently involves taking a substance found in the body, such as EPO or testosterone, supplementing the body's natural synthetic processes. Bicarbonate ion is produced in the blood, for example, from C02, and taking bicarbonate could be regarded in the same light. I myself wouldn't regard it as doping, but it could be debated, I suppose.

No one is suggesting that bicarb is doping (and I know you aren't suggesting it is). WADA define doping, so we don't have to make that subjective decision. Bicarb clearly isn't.

But in the manner it is used, it is a supplement and should have been noted on his anti-doping paperwork.

So many things are available as supplements that occur in the body or available via regular food or other means. e.g. is a Vitamin D pill a supplement? Yes, it is.

And so is bicarb. Indeed the AIS lists bicarb in it supplements classification under Group A:
http://www.ausport.gov.au/ais/nutrition/supplements/classification
along with e.g. probiotics, iron, beet juice, creatine.

Really though, use of bicarb as an ergogenic aid is a red herring to the discussion except as it points to the probably timing of ingestion of the caps.

It's the contamination of the caps that I'm interested in understanding plausibility of based on the data we do have:
- timing of probable use (IOW when one would have taken bicarb tabs)
- the likely level of contamination of caps filled by Impey himself
- the metabolism of probenecid
- level required to trigger a positive
- the subsequent negative tests
 
neineinei said:
He tested positive the day of the TT (Feb. 6). He was also tested Feb. 8 (no race) and Feb. 9 (road race), but the tests "yielded no adverse results".

He might have been taking his homefilled gelatine capsules all these days, but only the one/ones he took on the day of the TT was contaminated? Or did he only take them for the TT, or prior to the South African Championships so that the probenecid was out of his system by the 8.

http://www.darylimpey.com/News/DisplayNewsItem.aspx?niid=34129

The sodium bicarbonate in the Nuun tablets might be there to make them fizzy when put into water, to better disolve.

Some have made a point of him not declairing the capsules on the doping test form. But do we know that as a fact?

No, we don't, but I'd have thought this would have been noted in the reports as corroboration of the story.
 
Dec 7, 2010
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TailWindHome said:
So 70kg athlete say a 15g dose

3g every half hour
6 500mg capsules.

Doesn't seem unreasonable
That's 6 capsules, every half hour, over approximately 3 hours.

That, to me, would seem to indicate an almost compulsive level of attention to detail for these pills. At the very least, Impey would be placing a significant amount of importance on their consumption.

Which brings me to this...
westerner said:
So my questions/what I find odd is

1. why not just call around and find what you want in the first place (is this item hard to find in SA?)
2. seems odd a pharmacist would take a number and call a client later in the day for such a small item, that the client probably picked up at the pharmacy down the road?

...or could have happened as explained.

He went early in the morning to buy them, he said, but the pharmacy did not have any. Later, the pharmacist called Impey to say that he found some and Impey returned in the afternoon to buy them.
That part of the story seems a bit wanting to me. If these pills were so important to Impey (and have we anything to suggest that they were not important to him?), then that raises a few more questions.

Why wouldn't Impey have a reliable and ready source for empty capsules?

Why wouldn't he have just bought them in bulk packaging ahead of time?

If the pharmacist didn't initially have any, why was Impey unable to find them anywhere else in the time that it took the pharmacist to call him? If these were so important to his performance, how long was he going to wait to find another source?

Did have a previous relationship with this pharmacist or did he provide his contact info to someone who wasn't able to supply him with the one thing he was looking for upon his first visit?

How many capsules did Impey get from this pharmacist? Because I would like to imagine that having a stock of empty capsules would be something fairly standard for any pharmacists, but I will defer to any pharmacists (except one from Durban) who suggests otherwise. My point is: Is it likely that the pharmacist wouldn't have ANY capsules on hand? Was Impey requesting a huge order?

I'm having a hard time with that part of the story. How did it all unfold?

Pharmacist: "No, sorry. I don't have any capsules on hand. You're the only person that has requested them recently, and I don't really have a use for them on a regular basis."

Two hours later...
"Oh wait!"

Or

"You won't believe this. I am, as you might imagine, usually very well stocked on such an item, but it's just your bad luck to catch me at a time when my stock is fully depleted. I guess I won't be fulfilling any orders that require empty capsules for any of my customers until I get some more."

Or how about:

"I'm sorry, I don't have any empty capsules. They shouldn't hard to find though, here are a few places you might try...but don't call anyone for a couple of hours just in case I do find some just laying around." :rolleyes:

Call me a cynic, but WTF?
 
What has happened here is that some of you have got really really excited at a doping scandal and have been disappointed. You're like a kid at Christmas who didn't get the X-Box they wanted. You're angry and upset, I understand that, and in a state of denial and grief you are trying to revive the scandal by dismissing evidence you haven't seen and concocting ever more elaborate alternative scenarios. Let it go. Accept that you were wrong this time and he's most likely innocent. Maybe next time you'll be more lucky.
 
neineinei said:
The sodium bicarbonate in the Nuun tablets might be there to make them fizzy when put into water, to better disolve.

I don't think so. See [1] for a short discussion from the nuun blog.

What are the rules for what you are supposed to declare on the dope test form? Would you declare caffeine if you had a caffeinated clif bar? Would you declare vitamin b capsules? You normally don't declare your nutrition do you? I can see how baking soda blurs the line between supplement and nutrition.

I mean honestly, Impey could have said he was putting anything in those capsules. Creatine (legal), glucose (legal), table salt (legal). Why would he claim baking soda if it were a cause for suspicion? I think focusing on the baking soda supplementation is distracting from the real story, which is determining whether cross-contamination is plausible or probable.

edit: yea, what Alex Simmons said

[1] http://nuun.com/blog/2014/01/10/electrolytes-hydration/
 
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Parker said:
...and concocting ever more elaborate alternative scenarios.

No, I think the athletes themselves will always come out on top at that game. It's something they tend to excel at.

Besides, much of this isn't about who's right or wrong. It opens up other lines of discussion that have their own value.

Cross-contamintion from automatic pill sorters is something I personally find interesting and worth knowing about.

The effectiveness or not of sodium bicarbonate in athletics is also worthy of discussion.

The delays in notification from SAIDS are worthy of discussion.

Not to mention, this is pro cycling were talking about. Pro Cycling.
The theater of the absurd reaps what it has sown.

Outrageous conjecture and speculation?
So what? It's entertaining. And more so than most races.
 
Alex Simmons/RST said:
No one is suggesting that bicarb is doping (and I know you aren't suggesting it is). WADA define doping, so we don't have to make that subjective decision. Bicarb clearly isn't.

But in the manner it is used, it is a supplement and should have been noted on his anti-doping paperwork.

Since when do athletes have to list the supplements they’re taking? I thought it was up to them to decide to take anything that isn’t banned, and be responsible for any contamination that turns up. Are they required to list certain non-banned substances they’re taking?

So many things are available as supplements that occur in the body or available via regular food or other means. e.g. is a Vitamin D pill a supplement? Yes, it is.

And so is bicarb. Indeed the AIS lists bicarb in it supplements classification under Group A:
http://www.ausport.gov.au/ais/nutrition/supplements/classification
along with e.g. probiotics, iron, beet juice, creatine.

Just about anything can be defined as a supplement, but if it isn’t banned, and it isn’t required to tell anyone you’re taking it (as I believe is the case), then any list is arbitrary. You could argue that carbo-loading is taking a supplement.

It's the contamination of the caps that I'm interested in understanding plausibility of based on the data we do have:
- timing of probable use (IOW when one would have taken bicarb tabs)
- the likely level of contamination of caps filled by Impey himself
- the metabolism of probenecid
- level required to trigger a positive
- the subsequent negative tests

The mimimum level of detection required by WADA I believe is 0.25 ug/ml, at least as of a few years ago. However, there are methods available for greater sensititivity, at least as low as 0.05 ug/ml.* This would correspond to about 10 ug in a 200 ml. sample of urine. I haven’t yet found a study that enables an estimate of the urine concentration of the drug at various times following an oral dose, but an upper limit, most certainly an overestimate, would be to assume all of the drug is excreted within several days. This assumes all the drug initially goes into the bloodstream, which is almost never the case. A significant portion of it usually partitions into the tissues, and only very gradually find its way to the urine.

Assuming a four hour plasma half-life, about the minimum reported, most of the drug would be excreted within 12 hours, within a urine output of perhaps 500-750 ml. For that urine to average 0.05 ug/ml., about 25 ug of the drug would have to be consumed. If we assume only a peak urine concentration of 0.05 ug/ml is necessary, maybe a little less, but not much less, given such a rapid excretion. This, again, is a minimum estimate, assuming a maximum estimate of how much consumed drug is quickly excreted. Depending on how much of an oral dose goes into various tissues, it will be increased, probably by a factor of 2-5 or more. I don’t know the size of the tablets the pharmacist claims to have been counting, but perhaps on the order of 500 mg? So it would be a very small portion of one tablet.

This analysis is based on the minimum likely to be detected. We don't yet know the level detected in Impey. If it was a lot more, the amount of contaminant of course has to go up proportionately.

*This study, though, used spiked samples, in which prob was added directly to the urine. The problem is that according to this study, most consumed prob is metabolized before excretion, so unless the metabolites are detected, the detection level of prob in relation to the amount consumed would be effectively lower.
 
Dec 7, 2010
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Merckx index said:
So it would be a very small portion of one tablet.

Could you clarify this a bit?

Do you mean, a very small portion of the CONTENTS of one 500mg tablet?

Or that there would only need to be a "very small portion" of Probenicid that made its way onto the exterior on one tablet?

Which raises anther question:
Are the tablets already sealed, in one piece, when being processed through a counting machine, or are they open, in separate halves?

I'm not clear on how the contamination could occur. Would it be on the exterior or interior of the capsules?

And could you further define "a very small portion"?

Thanks
 
Granville57 said:
Could you clarify this a bit?

Do you mean, a very small portion of the CONTENTS of one 500mg tablet?

Yes.

Which raises anther question:
Are the tablets already sealed, in one piece, when being processed through a counting machine, or are they open, in separate halves?

I'm not clear on how the contamination could occur. Would it be on the exterior or interior of the capsules?

And could you further define "a very small portion"?

Thanks

By tablet, I mean probenecid. As tablets of this substance are processed in a counter, a tiny amount of material may flake off and contaminate the instrument. Then when capsules are processed, some of this material adheres to the latter. I assume the capsules are sealed or closed, and any contamination occurs on their outside.

This is my understanding, but if we have a pharmacist here, maybe s/he can provide a better view of what is proposed to have happened. But assuming this is correct, when Impey then filled the capsules with bicarbonate, some of any contaminating prob would have come off on his fingers. Possibly he could have ingested some in that manner as well, though a lot surely would have been lost. Whatever remained had to be enough to trigger the positive.

As I alluded to before, it would be possible to test this theory. Just run some prob tablets through the counter, then process some capsules. Then soak the capsules in a medium to extract any contaminating prob, and assay it. If Impey's experts actually did this, and detected enough that, taking into account the drug's pharmacokinetics, could account for his detected level, then he has a very good case. It still wouldn't prove that that was what happened, it could be a phony story that worked out for him, but I could understand his winning the case in those circumstances. If they didn't do this, but just estimated that there would be enough contamination, then I'd expect an appeal. But if that were the case, I wouldn't think SAIDS would accept the story in the first place.

By the way, bicarb tablets are available. It would seem simpler to buy and use them, but maybe they don't come in doses as large as he wanted. And I think Gran alluded to the fact that one could probably just buy a box or bottle containing a known quantity of empty capsules. I'm a little surprised that someone would buy them from some bulk source and have them counted out. But I'm not a pharmacist.