Weed in pasture was behind horse’s failed drug test, FEI Tribunal finds


Datura stramonium var. tatula (L.) Torr flower
Datura stramonium var. tatula (L.) Torr flower. © Skäpperöd [GFDL or CC-BY-SA-3.0], via Wikimedia Commons.
An endurance horse who tested positive for scopolamine most likely came to have the drug in his system through ingesting a paddock weed, the FEI Tribunal has ruled.

Fadista Das Tapadas, ridden by Carlos Cunha, of Portugal, took part in a 1-star 80km endurance ride in Madrid, Spain, on May 19 last year.

Samples taken from the horse on the day subsequently tested positive for scopolamine.

Scopolamine is a parasympatholytic drug used as a smooth muscle relaxant for the treatment of gastro-intestinal spasms. It is listed as a controlled medication under the equine anti-doping rulings.

From January 1 it will be formally identified as a specified substance – a category of substances recognised as able to enter a horse’s system inadvertently due to a credible non-doping explanation, such as pasture contamination.

Such cases will allow the FEI and the tribunal more flexibility when prosecuting a case or when making a sanctioning decision.

Cunha was advised in July last year of the positive test result from the endurance ride and waived his right to have the B sample analysed.

Cunha and the FEI subsequently agreed to the circumstances surrounding the case and submitted a written summary to the FEI Tribunal, comprising Armand Leone, Henrik Arle and Cesar Torrente.

The rider argued that the scopolamine in his horse’s system arose due to the horse inadvertently eating Datura stramonium in his paddock.

Cunha had made inquiries and discovered that scopolamine was a secondary metabolite of plants such as Datura stramonium, originally native to America but now an invasive weed widespread in Spain and Portugal. His stable was in Portugal, just 1km from Spain’s border.

The weed is a plant in the nightshade family and is known by several other names, including  jimsonweed, devil’s snare, stinkweed, locoweed, pricklyburr, false castor oil plan, devil’s cucumber, and thornapple.

This plant was present where he kept his horses. He provided photographic evidence of the plant growing in the paddocks at his stable, as well as other supporting documentation.

He argued that he bore no fault or negligence for the rule violation.

As soon as he realized the source of the positive finding he removed his horses from the paddocks and boxed them. He contracted a company to remove the plant from the paddocks.

Cunha provided insights into his day-to-day care of his horses. He took care of his endurance mounts himself. Mostly, they were kept in paddocks, eating grass and hay, with access to a salt block.

He did not give any vitamins or supplements to any of the horses under his care in order to avoid a potential doping case.

Datura stramonium.
Datura stramonium. © Taka [GFDL or CC-BY-SA-3.0] via Wikimedia Commons
When horses were unwell, only his veterinarian prescribed and administered treatments. Cunha said his vet was aware of his commitment to the FEI rules.

The FEI said Cunha’s explanation as to how the scopolamine came to be in the horse’s system was plausible. It noted that Datura stramonium contained a high quantity of toxic alkaloids, one of them being scopolamine.

The rider had proven that the plant was present at his stables and had been easily accessible to the horses.

It said it was satisfied that Cunha had shown how the scopolamine came to be in the horse’s system.

The FEI acknowledged that Cunha had measures in place to avoid drug breaches, and was aware of the high risks related to using supplements. He also did all the grooming work himself, which reduced the risk of misconduct by support personnel.

Therefore, the FEI acknowledged that Cunha had a certain level of knowledge and understanding of the FEI equine anti-doping programme and rules, as is expected from a rider.

“The FEI has had several cases involving an adverse analytical finding of scopolamine due to the intake of Datura stramonium or similar plant.

“Most of these cases involved … horses from South Africa. The danger of contaminated feed with Datura has long been recognised in South Africa and is a well-known risk in the equestrian and livestock community of that region.”

Datura stramonium.
Datura stramonium. © Taka [GFDL or CC-BY-SA-3.0] via Wikimedia Commons.
The FEI said it would be difficult for Cunha to know all species of plant that could occur in his stable or in the stable’s vicinity that could cause a drugs breach. “But should [he] have known this particular plant and the dangers related to this plant?

“The FEI believes that although Datura stramonium has invaded Portugal and Spain, its presence and associated risks, such as its toxicity and its potential to cause positive doping tests, have not yet been widely recognised by their habitants.

“The FEI is thus satisfied that in the present case, and especially taking into account [his] day-to-day routine and manner of care of his horses, he has demonstrated that he bore no fault or negligence.”

This meant the usual six-month suspension would not apply. The FEI agreed that there should be no sanction at all other than the disqualification of the horse’s results at the event.

The tribunal agreed that exceptional circumstances applied in the case, and said it was satisfied the agreement between Cunha and the FEI constitutes a bona fide settlement of the case.



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One thought on “Weed in pasture was behind horse’s failed drug test, FEI Tribunal finds

  • December 12, 2018 at 4:46 am

    Every horse owner should be able to recognize poisonous plants in their area and remove them. There are many resources, and it’s inexcusable to not be aware and take action.


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