South Ayrshire beaches continue to be blighted by washed up rock-like material that is thought to be palm oil, leading to countless visits to vets for dog owners whose pooches chow down on the seemingly irresistable stuff.

The most recent instance occurring just last week, when a Prestwick woman ended up with an expensive trip to the vet after her pet ingested the problem substance.

Lesley McPherson was walking her three-year-old Spanish Water Dog, Bee along Prestwick Beach when she came across a hand-sized honeycombed stone.

Lesley said: “She was running along, playing with her ball, near the seaweed. I was walking slightly ahead and I just turned around and saw her head down, in something and I thought what is she eating, I grabbed it and it was palm oil. She had a good mouthful of it, I tried to get it out of her mouth but it had already been ingested.

“I called the vet immediately and he said to bring her straight up. The vet said it can be quite dangerous to dogs, it can cause lots of problems in their digestive system.

“They gave her a very horrible injection to make her sick and the vet said when it did come up it was very oily, salty and smelly and so that confirmed for him that it was palm oil.”

The substance is thought to wash up on beaches after being dumped in the water after being used by ships to clean their tanks, which they are legally allowed to do if they are at least 12 miles out from the coast.

Lesley questioned why this should be allowed, given the harm it is causing: “This is something that needs to be put on a petition, to go to MPs, something needs to be done nationally.”

Ayr MSP Siobhian Brown has backed Lesley’s call, in response to the issue she said: “As a dog owner myself I am deeply concerned by palm oil washing up on the beach and the current legislation which allows ships to dump waste like this at sea.

“I will be writing to the Environment Secretary to highlight this issue. I will also be contacting the International Maritime Organisation to ask about current regulations and the Maritime and Coastguard Agency to establish just how many potentially illegal dumps around our coast are investigated.

“I am passionate about keeping our beaches and the water surrounding them clean, but whilst we are playing our part in doing this on land, those using the sea have a corporate responsibility too. believe there should be tougher penalties for ships dumping large amounts of palm oil.

“I hope Lesley’s dog Bee makes a full recovery and that they feel confident enough to walk on our beautiful beaches once again.”

A Maritime and Coastguard Agency spokesperson said: “We always encourage people to contact their local Coastguard if they see a substance on the beach that they think shouldn’t be there.

“It has become common place to refer to this type of material on the beach as ‘palm oil’ without any positive identification having been made through analysis. Until the substance has been identified, as a precautionary measure we would advise that people in the area please keep their dogs within sight, preferably on leads, until there is further information regarding what the substance is.

“It is extremely difficult to trace the origins of where the ‘palm oil’ or waxy substance has originated from. The MCA raised the issue of these types of incident at the International Maritime Organization and were responsible for putting together the evidence to secure agreement to introduce a ban on discharge.

“This places far more stringent restrictions of what and where ships can legally discharge materials.

“The MCA is committed to the environment and our role in cleaner seas.”