Northern Ontario home to 50% of Ontario's blue-green algae problem

Northern Ontario was home to more than half of the blue-green algae blooms in Ontario this year.

Warmer water temperatures and weather conditions have caused the increase in blue-green algae, ministry says

Something called phoslock is being considered as a solution to the perennial algae problem in Greater Sudbury's Simon Lake. It would see tonnes of clay dumped into the lake, trapping phosporous in the lake bottom, so algae can't feed on it. So far, it's only been approved for use in a bay of Lake Huron. (City of Greater Sudbury)

Northern Ontario was home to more than half of the blue-green algae blooms in Ontario this year.

Blue-green algae blooms can cause itchy skin and, if ingested, can lead to fever, diarrhea and vomiting.

Ontario's Ministry of the Environment and Climate Change received 45 blue-green algae reports this year, said Dr. Michelle Palmer. Twenty-six of those blooms were in the north.

Palmer said there has been a steady increase in the quantity of blooms found in Ontario due to climate change and warming waters, but this summer was particularly bad because of weather conditions.

"So things like sunlight, rainfall, wind and cloud cover can all impact whether or not a blue green algal bloom will occur," she said.

In recent years, the ministry received about 25 to 30 reports of blue-green algae blooms. She noted more people are aware of the algae and are reporting it.

The province has been tracking the blooms since the mid-1990s.

Blue-green Algae FAQ

Q: What are blue-green algae?

A: Blue-green algae are primitive microscopic plants that live in freshwater lakes around the world. Normally, blue-green algae are barely visible but, given certain conditions, populations can rapidly multiply to form a large mass called a "bloom". Most blooms contain plant species that are harmless to human health; however, the presence of even one toxic species can pose a risk. Only laboratory analysis can determine whether or not a bloom is toxic.

Q: How can I recognize a blue-green algae bloom?

A: Blooms most commonly look like bluish-green pea soup; however, olive-green and red blooms have also been reported. When the bloom is very large, algae may form solid-looking clumps. Fresh blooms often smell like newly mown grass. Older blooms smell like rotting garbage.

Q: Should I be concerned about blue-green algae?

A. Yes, you should be cautious, particularly during an algae bloom. Contact with toxic species of blue-green algae can result in the following symptoms:

  • Itchy, irritated eyes and skin if you bathe, shower, swim or water ski in contaminated water,
  • Headaches, fever, diarrhea, abdominal pain, nausea and vomiting if you swallow contaminated water and more serious health effects if contaminated water is consumed in large quantities.
  • Animals, particularly dogs, are at greatest risk of illness and death and should be kept away from surface water sources during a bloom. Symptoms of blue-green toxin poisoning may range from lethargy and loss of appetite to seizures, vomiting and convulsions.

Source: City of Greater Sudbury


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