The presence of potentially toxic blue-green algae in a nearby lake has health officials concerned.
The Thunder Bay District Health Unit has issued the advisory for Warnica Lake just north of the city.
It says the Ministry of the Environment is doing an analysis of a water sample taken from the lake to test for any toxins.
The Heath Unit cautions water should be avoided whenever a blue-green algae bloom is present, and for about 2 weeks after it has gone away because blue-green algae has the ability to turn toxin production on and off.
