New Brunswick

What you should know about toxic algae blooms if you're heading to the St. John River

If they can kill dogs, blue-green algae can harm people too, an associate professor of biology says.

'No reason to risk it': Blue-green algae could also be harmful to humans, UNB scientist says

From left to right, Sookie, Peekaboo, and Nike all died suddenly over the weekend after playing in the St. John River in the Fredericton area. (Photo: Submitted)

If they can kill dogs, blue-green algae can harm people too, says a scientist at the University of New Brunswick.

Janice Lawrence, who studies cyanobacteria, also known as blue-green bacteria, is advising people to stay away from the St. John River, particularly in areas below the Mactaquac Dam, in the Fredericton area and even as far downriver as Jemseg.

Her warning comes after at least three dogs died suddenly after swimming in the St. John River over the weekend.

Two of the dogs died in Carleton Park in Fredericton on Sunday evening. Another dog died Friday at Hartt Island RV Resort, 14 kilometres west on the river.

"The toxins would have a similar effect to any vertebrate that's exposed to them," said Lawrence, an associate professor of biology.

Right now we don't really know what's going on and what caused the dogs around the St. John River to die.-Dr. Janice Lawrence, associate professor of biology

"Frighteningly, that means if a dog is exposed and can accumulate toxins and die from it, then a human can too."

The toxins can attack the nervous system, liver and skin, and there is no cure.

Although the province doesn't know exactly what caused the deaths of the three animals, the provincial veterinarian, Dr. Jim Goltz, has said he suspects blue-green algae.

Lawrence said people should avoid the water — at least until the province has identified the cause. Water can move from one region to the next at a fast pace, she said.

"For now there's no reason to risk it," she said. "I wouldn't be playing in inshore areas right now."

Avoid splashing around

Two of the dogs died after visiting Carleton Park on Sunday. (Adam Travis/@adamtravis_)

"I will still go rowing tomorrow on the St. John River. I won't take my dog there and I won't take my young son to go play around at the water's edge.

"When I come home, I will have a good shower and wash everything off and be aware there are symptoms I would be on the lookout for."

Although humans and dogs interact with water very differently, Lawrence said people should avoid lapping up lots of water by slashing or paddling then breathing in the air.

Even if the water is not blue-green, there could be toxins from the bacteria, she said.

Janice Lawrence, an associate professor of biology at the University of New Brunswick, advises people to stay away from the St. John River below the Mactaquac Dam down through the Fredericton, Maugerville and Sheffield areas to Jemseg. (Photo: CBC)

"My dog rolls around, licks herself off, ingests massive amounts of water … the same goes for young children … they may ingest more when they're swimming," she said. "Therefore they have a higher chance of picking up toxins and becoming ill."

Lawrence said smaller animals and humans have a larger surface area relative to their mass and can accumulate toxins more easily if they come across their skin.   

"Don't go roll around in blue-green scum even though that may not be necessarily be toxic," she said. "Right now we don't really know what's going on and what caused the dogs around the St. John River to die."

Toxins have killed other dogs

Veterinarian Dr. Jim Goltz suspects blue green algae as the cause of death. (Catherine Harrop/CBC)

Goltz, the provincial veterinarian, said two of the dogs are receiving a necropsy examination — one from each site.

Once he receives the results, Goltz said, he will report back to the dogs' veterinarian, the Department of Health, the Department of the Environment and the Department of Agriculture, Aquaculture and Fisheries.

Goltz said other dogs have died in the past under similar circumstances.

The last case was in 2010, when a Labrador puppy died from blue-green algae toxicity after swimming in the St. John River below the Mactaquac Dam in the Island View area.

What happens now?

Dr. Na-Koshie Lamptey, regional medical officer of health, said she has been looking at both areas where the dogs were swimming before they died to try and determine the cause of their deaths. (CBC)

The Department of Health is scanning the two sites where the dogs were swimming for potential health risks to humans.

Dr. Na-Koshie Lamptey, regional medical officer of health, said the department is looking for anything unusual in or near the water, including signs of blue-green algae and other potentially harmful things. 

Lamptey said she still doesn't know if the dogs' deaths were caused by blue-green algae.

"The point of doing the investigation is to get the information to pursue a number of different possibilities so we're doing that in a step-by-step fashion."

But if residents do decide to go into the water, they should cover open wounds, avoid swallowing water and bathe immediately after contact, as the bacteria can also lead to skin irritation and rashes. ​

"Residents should understand there is some risk associated with contact with any recreational body of water and they should always take precautions," she said.

What are blue-green algae?

Blooms can range in colour from dark green to yellowish brown and is typically found in waterways this time of year. (Grand River Conservation Authority)

Blue-green algae are bacteria that have the capabilities of photosynthesis, harvesting the sun's energy to function. They can be found in different types of water systems and soils.

But there are some cyanobacteria that can produce toxins, and if those bacteria start to bloom and accumulate in high numbers, the toxins they're producing can also accumulate.     

Dog owners warned to keep pets away from St. John River

3 years ago
All 3 dogs died over the weekend in the Fredericton area 0:48

Blooms can range in colour from dark green to yellowish brown.

"A lot of the cyanobacteria that we're talking about, that we're concerned about, are fed by the different types of compounds that we put down our drains, that we put on our lawns,"  Lawrence said.

"We're talking about basic fertilizers, nitrogen, phosphorus."  

Lawrence said they can come into water sources from laundry detergents, soaps for washing cars, fertilizer on golf courses and excess manure run-off from farms.

Warmer temperatures a factor

Scientists still don't know why some bacteria produce toxins and others don't.

But with warmer temperatures and longer summers, there's a greater chance of seeing a rapid increase of these toxins, she said.

Warmer water temperatures and different wind patterns can also result in changing water currents. This can create different conditions that will allow new organisms to take over an environment where there wasn't a problem before.

"We're looking at a rapidly changing scenario," Lawrence said.

With files from Information Morning Fredericton, Angela Bosse