Swimmers urged to take precautions with blue-green algae warning in effect along Saint John River

The beach at Mactaquac Provincial Park is the perfect place to soak up the sun and cool off in the water, especially with the province under a heat warning this weekend.

However, the blue-green algae plaguing lakes and rivers in New Brunswick — there are multiple warnings in effect — can be harmful to pets and humans.

The regional medical officer of health says anyone swimming should take precautions.

“Make sure that you’re appropriately supervising people or animals that can’t supervise themselves, so young children or pets that might swallow the water or eat anything that’s dried up on the shore,” said Na-Koshie Lamptey, the regional medical officer of health.

Lamptey recommends rinsing off as soon as you get out of the water, and she says not to get in the water if you have cuts or open wounds.

Although it’s uncommon for people to get sick, there are some symptoms to watch for.

“They could experience abdominal pain and cramps, and diarrhea. If they come into contact with the toxin that irritates the gastrointestinal tract they could experience signs of numbness or weakness or tingling in their muscles,” said Lamptey.

The biggest misconception about blue-green algae, or cyanobacteria, is that they’re algae at all.

“One of the confusing things is they were originally identified that way because they live in the same environment as algae, but they are photosynthetic bacteria,” said Janice Lawrence, an associate professor of biology at the University of New Brunswick.

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The bacteria produce toxins that can affect the liver, nervous system and skin and there is no treatment.

“You aren’t going to get neurotoxicity from having this toxin on your skin, although I still wouldn’t recommend it because we don’t know what would happen,” said Lawrence.