Blue-Green Algae in Muskoka Lakes Twp

Posted: 2018-09-15 17:41:10 By: hbr

Residents around Leonard Lake in Muskoka Lakes Twp are being cautioned by the Simcoe Muskoka District Health Unit (SMDHI) about a potential blue-green algae bloom.

The Ministry of the Environment, Conservation and Parks (MECP) has collected water samples to confirm the presence of blue-green algae. Wind and water currents can change the location of algae blooms, which may make the water look bluish-green, or like green pea soup or turquoise paint and may also appear like balls or clumps of algae.

Swimming and other water sport activities should also be avoided in areas where the blue-green algae bloom is visible.

Exposure to blue-green algae, whether for drinking, swimming, bathing, cooking or through eating fish caught from the lake, can result in illness. Affected residents are being asked not to use the water for drinking or food preparation, including breastmilk substitute (infant formula). Some varieties of blue-green algae are capable of producing toxins that can be harmful to humans and animals. Boiling the water will not destroy the toxins, and home treatment systems should not be relied on.

Adverse health effects are mainly caused by drinking or coming into contact with water that is contaminated with blue-green algae toxins. Symptoms from consuming toxins can include headaches, fever, diarrhea, abdominal pain, nausea and vomiting, and can be more serious if water is swallowed in large quantities.

SMDHU and the MECP will continue to monitor the lake and updates will be posted on the health unit’s website at