News Release
July 17, 2018

Toronto Public Health (TPH) has received confirmation from the Ministry of the Environment, Conservation and Parks of the presence of blue-green algae blooms at the mouth of Mimico Creek and in Humber Bay Park East. Water samples taken and tested by the Ministry indicate the presence of blue-green algae.

Cyanobacteria, commonly referred to as blue-green algae, are plant-like organisms that can range in colour from olive-green to red. Blue-green algae occurs naturally in a wide variety of environments including ponds, rivers, lakes and streams. The algae is easily visible and should be avoided due to the potential health risks associated with it.

Some species of blue-green algae have the potential to produce toxins that are harmful to the health of humans and animals. Adverse health effects are mainly caused by drinking and coming into contact with water that is contaminated with blue-green algae toxins.
Exposure to blue-green algae toxins, if present in sufficient amounts, can cause the following symptoms:
• Headaches
• Fever
• Diarrhoea
• Abdominal pain
• Nausea or vomiting
• Skin rashes
• Mucous membrane irritation

TPH encourages residents to take precautions when visiting this part of the Toronto waterfront. Beaches in this area are not regularly monitored for water quality or supervised by lifeguards. Members of the public are urged to not enter the water in this section of Mimico Creek and to avoid contact with or ingestion of the water. Residents should also avoid allowing pets to enter the water in Mimico Creek.

Individuals who come into contact with the water should wash themselves off as soon as possible with clean water. If any of the above symptoms are experienced following a potential exposure to blue-green algae, contact a health care provider.

More information is available at

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Keisha Mair
Toronto Public Health