PET owners and parents are being warned of the dangers from toxic blue green algae after it was found in a York lake.
Signs have gone up across the University of York, saying that Blue Green Algae is present in and on the surface of the lake at the heart of the campus.
They tell visitors: “For your own health and safety, you are asked not to have any contact with the lake water or wildfowl.”
A spokesperson for the university, which is open to the public and regularly visited by dog owners and children coming to feed the ducks, said it had put the signs in place to inform campus users there was blue green algae on the lake and advise them against any contact with the lake water.
“We have had blue green algae on the lake in the past and this year it is likely to be around until early to mid-October,” they said.
“As always, we ask campus users to refrain from feeding the birds on campus and to keep dogs on a lead.”
The problem comes as vets have urged pet owners to take extra precautions when walking their dogs near lakes and rivers, after a spike in reports of toxic blue green algae in August.
The British Veterinary Association (BVA) said the algae or cyanobacteria was a group of bacteria that could contain dangerous toxins which can be harmful and even fatal to pets, even if ingested in small quantities.
It said the death of at least one dog – a British Bulldog – had been linked to such exposure in the summer.
“Blue green algae blooms may appear as green or greenish-brown scum on the surface of water,” said a spokesperson.
“Dogs can swallow it by drinking water from an affected lake, river or pond or while licking their fur after going for a swim.
“Symptoms of exposure can appear within a few minutes or hours, depending on the type of toxin ingested, and commonly include: vomiting, diarrhoea, drooling, disorientation, trouble breathing, seizures and blood in faeces.
“If left untreated, it can cause liver damage and ultimately be rapidly fatal.”
BVA president Daniella Dos Santos said: “We know that some dogs enjoy nothing better than a paddle in a cool lake while on a walk, but we’d urge pet owners to keep their dog on a lead during walks near water confirmed to have toxic algal blooms.
“There is currently no known antidote for the toxins, so prompt veterinary treatment is the only way to tackle their effects and ensure a good chance of recovery for your pet.
“If you suspect your dog has been exposed to blue green algae, seek emergency veterinary treatment as soon as possible.”
An Environment Agency spokesman said the algae was sometimes found at Gormire Lake near Sutton Bank, and said the toxins could kill wild animals, farm livestock and domestic pets.
“In humans, they can cause rashes after skin contact and illnesses if swallowed,” he said.
“Not all blue-green algae blooms and scums are toxic but you can’t tell just by looking at them so it’s best to assume they are.”