Denis Lynch said he can explain how Latinus tested postive for capsaicin, the banned substance that prevented him and three other riders from competing in the individual show jumping final at the Olympic Games, Aug. 21 in Hong Kong, China.

He commonly applies a topical substance called Equi-block to his horse’s back to loosen the muscles before working, he said. The label on the bottle he produced read, “Contains capsaicin—will not test.”

“He used it the entire year, including in his wins at La Baule [France] and Rome [Italy], and the horse has always tested negative,” said Irish team veterinarian Marcus Swail. “It was a considerable surprise to us that he tested positive today. Denis was so sure it wasn’t a problem that he didn’t even think to draw it to my attention.”

No show jumping horse has tested positive for capsaicin before this event, but the substance, derived from chili peppers, can be used to create a burning sensation or as a painkiller, said Fédération Equestre Internationale veterinarian Paul Farrington.

Lynch said he begged officials to allow him to participate in the final. “I don’t think I’ve done anything wrong,” he said. “I have nothing to hide. Latinus is ranked No. 1 in the world, and that says enough for him.”

Swail said the rules for allowed substances need to be more clear.

“The difficulty as a treating vet is that there isn’t a list of medications under a heading, where individual substances are listed. It’s not like you can go to a list and say [that substance] is OK or not OK,” he said.

“The nature of what is described in the list is very general, and the reality is that on too many occasions we only find out what is and isn’t allowed when people test positive.” David McDonald, director of Horsesport Ireland, said that Irish officials had taken extra precautions this year, after Cian O’Connor was stripped of the individual gold at the 2004 Olympic Games for a positive drug test from his horse, Waterford Crystal.

“We were absolutely keen to take every precaution that this wouldn’t happen,” McDonald said. “The horse was tested when he got here, although not for this substance, and he was negative. We made full use of the elective testing procedure when we got here. We’re about saying it as it is; we haven’t consulted lawyers. This is what we told the [FEI] Tribunal. It’s an absolute catastrophe for Denis and the horse. His chance for an individual medal is gone, and I can’t think of a more severe penalty.”

“I’m shattered; that’s it, shattered,” said Lynch. “I can’t say any more.”