Health officials are warning people living at or visiting Baptiste Lake about blue-green algae.
Blue-green algae produce a toxin that can cause serious illness to animals or humans who drink or have contact with contaminated water. Alberta Health Services says people and animals should not drink water from the lake, not even if it's boiled, as that doesn't remove the toxins. People and pets should not wade or swim in the water and they shouldn't eat fish caught from the lake.
AHS says the toxin can remain in the water even after the algae has moved or disappeared.
The advisory will remain in effect until further notice. Baptiste Lake is northwest of Athabasca.