A leading American endurance rider who is also a veterinarian has escaped suspension for a doping offence in Canada, after the FEI Tribunal accepted that contaminated “sludge” was to blame.

Nicki Meuten, 48, and her husband Don, also a rider and retired veterinary pathologist “suspended themselves” once notified of the positive result at the Coates Creek ride in July last year. This prevented their consideration for the 2018 World Equestrian Games, but Meuten said they did not want to be labelled cheaters – they were 100% for horse welfare and totally against drug and physical abuse.

Meuten’s horse FYF Dutch tested positive to the banned anti-depressant O-Desmethyl Venlafaxine (ODMV) after winning the CEI160km ride at the New Lowell, Ontario venue.

Ride coordinator Robert Gielen confirmed that the trail passed through “at least one field” used for dumping sludge, and that the ride base was located at a Girl Guides’ camp, on whose huge septic field many of the competing horses had grazed.

Meuten said it was her practice to let her horse graze and drink from natural sources along the trail, though at this ride she had taken care not to expose FYF Dutch to the pool and the lush grass at the ride camp. Meuten said neither of she or her husband personally took ODMV.

Tribunal agreed that: “Right next to the trail were standing pools of septic water, a pile of sludge and a sign. Environmental contamination with ODMV was now a documented common occurrence. It was present in effluent from treatment plants in Ontario, it was in drinking water and streams in USA and other countries.

“Given the sensitive testing of current methodologies combined with ODMV presence in our environment and the miniscule amount present in the urine of the horse, it was abundantly clear that contamination was the most likely scenario explaining how the ODMV entered the horse’s system.”

One scientific study presented took place at the Grand River in southern Ontario, where venlafaxine and its O- and N-desmethyl metabolites were present in untreated wastewater.

Meuten added: “After having researched the drug, it would be stupid for anyone to use it, as the side-effects were terrible, and neither was it a performance-enhancing drug. One of the side-effects was increased heart rate, which no endurance rider would want to risk.”

In these “exceptional circumstances,” Tribunal also waived a fine.

The full judgement can be read here.

Another rider also ruled out of WEG because of pending sanction for doping was handed a backdated 17-month suspension last week – Jessica Sternberg, 27, whose family has underpinned reining in Britain for decades.

Sternberg’s horse Shiners Chic tested positive to the banned steroid stanozolol at a 3* event in Katy, Texas in April 2017. The suspension ironically expires during the Tryon fortnight.

The standard two-year tariff was reduced after the FEI accepted the substance was administered without Sternberg’s knowledge or consent. She is mostly resident in London, UK, but spends a few weeks each year competing from her family’s Sterling Ranch at Pilot Point, Texas. Sternberg’s mother Rosanne is a renowned breeder of Quarter Horses.

Vet Dr John McCarroll admitted administering stanozolol two weeks before the competition. He attended Shiners Chic due to the non-availability of the ranch’s usual vet.

Sean Pulley, ranch manager for 17 years, understood that Dr McCarroll was solely injecting platelet rich plasma “to ease minor arthritis” in the front fetlocks.

The Tribunal decision notice states: “It was extremely shocking and distressing to the PR [person responsible] when she ultimately learned that this horse, which she had teamed with and shown for years, had been given such a substance.

“She has learned a costly and painful lesson that she cannot rely on even long-trusted individuals in order to ascertain the condition and treatment of horses that she rides.

“The FEI does not doubt the fact that the PR is a very good person with good intentions in relation to her horses, who is in a very difficult situation. The FEI has duly considered the facts and circumstances of the case and is satisfied that the PR has fulfilled the requirements for No Significant Fault and Negligence for the rule violation.”

The full judgement can be read here.

At Tryon next week, Jessica’s aunt Francesca Sternberg makes her fifth WEG appearance for Britain, while her uncle Doug Allen is chef d’equipe.