A blue-green algae bloom has been confirmed in Middle Muldrew Lake in Gravenhurst.
There are now five lakes in Muskoka affected by blue-green algae, according to the Simcoe Muskoka District Health Unit (SMDHU). The northwest shoreline of Mary Lake in Huntsville, the southwest shoreline of Bass Lake, the northwest shoreline of Leonard Lake, and Three Mile Lake (including Hammell’s Bay) all in Muskoka Lakes are also affected by blooms.
SMDHU officials say many species of blue-green algae can produce toxins that are harmful to humans and animals. They point out that the water infected by a bloom will look bluish-green, like green pea soup, or turquoise paint.
Officials say humans and animals should not drink or use the water from affected lakes, including water drawn from the lake by private water supplies, don’t swim in the area affected, “exercise caution” when eating fish caught from the area of the lake where the blooms are, and do not use herbicides, copper sulphate or other algaecides that may break open algae cells and release toxins into the water.
Symptoms following contact or consuming toxins from blue-green algae blooms can include skin, eye, or throat irritation, breathing difficulties, headaches, fever, diarrhea, abdominal pain, nausea, and vomiting. The symptoms could be more serious if a lot of the bad water is swallowed.