A health advisory was issued today for Fernan Lake by the Panhandle Health District and the Idaho Department of Environmental Quality. Water samples confirmed the presence of blue-green algae that can produce toxins harmful to humans and animals. The density of blue-green algae in Fernan Lake is likely to be associated with potentially harmful toxin concentrations in water according to World Health Organization guidelines. Therefore, the public is advised to avoid swallowing or inhaling water and to avoid direct contact with water containing visible algae. Drinking water from the lake is especially dangerous and the toxins cannot be removed by boiling or filtering the water. Children and pets are particularly susceptible/Panhandle Health District. More here.