Your Questions About Split Sample Testing (And More), Answered - Horse Racing News | Paulick Report

Your Questions About Split Sample Testing (And More), Answered

Over the past week we have received numerous emails asking questions about the split sample testing process, as the racing world waits for the next news in the Medina Spirit Kentucky Derby scandal. We got even more questions after Louisville Courier-Journal reporter Tim Sullivan revealed that the split sample taken after Medina Spirit's Kentucky Derby run hasn't yet been sent out for analysis.

We examined the process briefly last year when racing fans grew restless awaiting the split sample results from the 2020 Arkansas Derby card, but wanted to address a few of the questions that were specific to this case.

We spoke with Dr. Mary Scollay, executive director of the Racing Medication and Testing Consortium (RMTC) and former equine medical director for the Kentucky Horse Racing Commission, to learn more about how this regulatory process normally works. (Current staff at the commission are prohibited from discussing an ongoing case, particularly one like this where the split sample has not yet been tested.)

What's a split sample and how is it collected?

The split sample, or “B” sample, is collected at the same time as the primary sample, in the test barn after the race. Urine or blood is collected from the horse and subsequently divided into two containers. One of these is sent off for analysis by the laboratory contracted by the commission – in this case, Industrial Labs – for post-race testing. The other is stored under lock and key at the track at which it was collected.

If a lab finds and confirms a drug positive or overage in the primary sample, the trainer is notified and provided the opportunity to request to have the split tested. The trainer is allowed to select which lab will test the sample, and in many places is required to select a lab with a certain level of accreditation, like RMTC accreditation. All RMTC-accredited labs are capable of performing split sample testing.

How often are split samples negative, and what happens if they are?

If a split sample is negative, or if the split sample laboratory finds the substance in question at a level below the regulatory threshold, then there is no violation of the rules and therefore no ruling issued.

Scollay said that in her experience at the Kentucky commission, it was extremely rare for a split to come back negative.

“Maybe over 11 years, maybe there were four [cases where a split lab found a lower, legal level of a substance in question],” she said. “I can only think of one split in all those years where a laboratory reported a finding and the split laboratory did not detect it. And in that particular case it was a fairly obscure substance.”

Do split sample labs know whose sample they're testing?

They aren't supposed to. In normal circumstances, the lab would receive the sample from the appropriate jurisdiction and would be told which substance had been found, and in what concentration. They would not be told the identity of the horse, trainer, or race. All testing samples are assigned numbers at the time of sampling to keep them anonymous to the primary and split sample testing labs.

Scollay said the publicity around this split sample could lead to a reluctance from some laboratories to take the sample on – but she has also heard from at least one lab director who isn't convinced that would be a factor.

How is a split sample test different from the original test?

A split sample test would be the same as the confirmatory analysis run by the primary testing lab. When the primary testing lab gets a post-race sample, it will first screen the sample against its catalogue of substances to see if any of them are present. When it does identify one, it then must perform confirmatory analysis to decide how much of the drug is present in the sample.

The split sample lab will not screen the split against its catalogue, but will instead perform confirmatory analysis similar to what the primary lab did. The split sample lab is provided with the concentration from the original test only to help technicians choose the proper calibrators for an accurate reading.

“The estimated concentration, the reason that's provided is so they know what calibrators – known positive concentrations – they need to run in order to make an accurate determination about the concentration about the sample,” she said. “If you know the concentration is five, your calibrators might be one, two, five, seven, and ten. But if you don't know the concentration, your calibrators might be one, 10, 25, 50, and 100. Then you're not able to get a very accurate estimate of the concentration.

“You're trying to sandwich your unknown or your test sample in the middle of the range of known concentrations. Think of it of if you have eight or ten glasses of water and you put blue food coloring in one and keep diluting across glasses until it gets lighter and lighter. You've got a glass with blue in it and you're going to line that up to try and see which one of those tinted blues is closest to your color.”

It's not unusual for there to be as much as a 25 percent variability between labs when you get down to very small measures like picograms. For substances that have thresholds governing how much of a drug is considered legal, that can make a big difference. (In this case, however, there is no threshold for betamethasone so any amount would be considered a violation.)

Once the lab actually begins the analysis, it takes the same amount of time as the initial post-race testing – but the hold-up is usually scheduling. Dr. Scott Stanley told us last year that it's not unusual to wait three to four weeks in the non-busy season to get a split result back. Given the constraints of the COVID-19 pandemic on staffing levels, he expected the Charlatan split sample in 2020 to take six to eight weeks; in the end, stewards in Arkansas issued a ruling on July 15 for races run the first week in May.   

How is the split sample lab chosen, and how long does that take?

The process of choosing a lab depends on a few factors. Labs can reject a split sample request for various reasons. As we explained last year, contract work (like post-race and TCO2 testing) are the main priority for testing labs, because that's what pays their bills. Spring and summer are the busiest times for testing laboratories, as there is racing going on in more places than there is in the wintertime. 

Scollay said in her role at the Kentucky commission, it wasn't uncommon for labs to tell her it might take weeks before they would be able to promise a result – or even months.

“When I worked for the horse racing commission, it was my goal to make sure a trainer always had a choice and sometimes that meant two laboratories,” she said. “Laboratories would respond, 'We're way behind' or 'We've got a bunch of confirmatory analyses lined up' or 'Our turnaround time would need to be 12 weeks.'

“I can't remember the last time I got a positive response from all the RMTC-accredited labs. I don't know that I ever did.”

If there's any kind of back-up for the lab's regular work – new equipment, staffing issues, etc. – that has a ripple effect on regular testing and hence, split sample timeframes.

It can also matter what substance is involved; if the primary lab found an unusual drug, or an uncommon drug at a particularly small concentration and the lab getting the split sample request already knows it can't reliably test for that substance to the same limit, it will reject the split sample request. Scollay said that in this case, that shouldn't be an issue because betamethasone is a controlled therapeutic drug which testing labs would encounter frequently. She expects all RMTC-accredited labs to have the same sensitivity of testing when looking for this particular substance.

Why can't we eliminate delays by having trainers choose split sample labs and send samples off before the first round of tests come back?

For one thing, it would be incredibly expensive for either commissions or horsemen to pay for double testing to be done on every sample. For another, split samples aren't obligatory – a trainer can decide to waive his or her right to the test and take the penalty if they feel it's not worthwhile to fight the positive.

Most importantly though, Scollay said the differences in testing capabilities for rare substances, and the variation in timelines for each lab through the year would make it meaningless to choose a lab before knowing what substance might be at play.

“It would be foolish for a commission to consent to that, because if the lab can't do the work and the sample gets sent to them, a positive test gets negated and that certainly doesn't support the integrity of the game,” she said.

So when will Baffert be banned?

Hang on a minute. The Kentucky regulations are very clear about the penalties stewards may hand to a trainer for medication violations. While they're given a range of potential suspension lengths and fines to work within, they don't have the latitude to throw those out the window and revoke a trainer's license. Under current regulations, betamethasone is a Class C medication in Kentucky, and Medina Spirit would be Baffert's second Class C in 365 days if the split is positive. (Merneith's overage for dextrorphan and the two lidocaine overages from last year fall in different drug classes by Kentucky standards. So, although this is Baffert's fifth therapeutic overage in a year, it's only his second of this type.) The penalty range for a second Class C violation in 365 days is a 10- to 30-day suspension and a $1,500 to $2,500 fine.

Scollay said there is a catch-all rule in Kentucky, as there is in many places, designed to deal with conduct “contrary to the best interests of racing,” but that's typically reserved for more extreme situations, not therapeutic overages.

What about the disqualification of the horse?

The same Kentucky regulation, KAR Title 810, Chapter 8, Section 030, states that a first Class C offense for an owner “shall” result in disqualification and loss of purse. Unlike trainer penalties, there is no language included allowing for stewards to consider mitigating circumstances. Medina Spirit owner Amr Zedan has engaged an attorney who's already preparing to argue that the stewards aren't bound to disqualify a horse.

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