MYSTERY surrounds a toxic pollution scare on the River Dart in which a dog almost died.

One Totnes pet owner came within half an hour of seeing his two-year-old dog Bertie face an agonising death after the animal swallowed toxic palm oil which had been wash­ed up on the foreshore off Steamer Quay.

It was only his quick action in rushing Bertie to a vet that saved him, said the dog's owner Nathaniel Holmes.

Now Mr Holmes is warning other dog owners that the potentially deadly pollution is in the River Dart, after spotting the lard-like substance floating in the river as far up as the Totnes bridge.

And Totnes-based Dart Vale vets, who treated Bertie, said they would be issuing a warning on their website page and on Facebook to get the message out.

But Dart harbourmaster Rob Giles said he was skeptical about the facts of the incident – which would be the first time he had heard of palm oil being washed from the open sea that far up the river estuary – and the South West Environment Agency said there had been no reports of palm oil in that area.

Mr Holmes, who lives in Totnes, said he had spotted clumps of rancid palm oil alongside Longmarsh and Vire Island – both popular with dog walkers.

'It is horrible stuff and causes liver and kidney failure in dogs who eat it,' he said. 'People should just keep their eyes peeled anywhere there is tidal water.'

Des McEvoy, Dart Vale vets practice manager, said, too, this was the first time he had heard of it being carried up the River Dart.

Bertie, a cross between a Labrador, border collie and poodle, was out with Mr Holmes's wife Leoni along Streamer Quay when he smelled something and jumped over a wall on the foreshore, said Mr Holmes.

'It was low tide and, before my wife could stop him, he had grabbed hold of a big chunk of palm oil and was wolfing it down,' he said.

'She quickly stopped him and brought him home. We had seen palm oil there in the past, so we knew what it was and we knew it was a big problem.

'We telephoned Dart Vale vets and fortunately they had a vet there on duty and we took Bertie straight over. The vet saw him straight away and induced vomiting and he threw up a huge amount of palm oil.

'The vet said that if we hadn't acted quickly it would have destroy­ed his liver and he would have died. Another half an hour and it would have entered his digestive system and that would have been more problematic.'

Mr McEvoy said that last year the practice had issued a similar warning after the pollution was discovered on beaches at Paignton and added: 'I don't think it has ever come up the River Dart before.'

Cpt Giles said he had received no official report of the incident from either the Coast­guard or RSPCA and therefore had no information on it.

He said he would investigate further if the dog owner or vet would like to get in touch and show him where the spill was. 'I doubt whether palm oil from the open sea would get washed that far up the river estuary,' he said.

And if it was, it would be the first incident of its kind that he had come across in his five years as harbour master, he said.

He said pollution incidents of this kind were very rare: 'It is probably less of a worry than e-coli bacteria being washed down the river.'

A spokesman for the South West Environ­ment Agency said there had been no reports of palm oil in that area.

For months now the palm oil – thought to come from ships swilling out their tanks illegally in the English Channel – has been appearing on beaches in Devon to Cornwall.

After palm oil was found on South Hams beaches in 2013, South Hams Council warned dog owners to keep their animals on leads.

A spokesman said at the time: 'Although the Environment Agency has assured us it isn't harmful to humans, it could be dangerous to dogs if they eat a lot of the substance.'