The Oregon Health Authorities is reminding those recreating and using bodies of water this summer that cyanobacteria blooms can produce toxins dangerous to humans and animals. Cyanobacteria are beneficial and found in all freshwater. However, in some conditions produced by warmer temperatures in water and the atmosphere combined with nutrients and water chemistry, the naturally occurring bacteria can multiply and produce cyanotoxins that make people sick. Since monitoring is limited, it is up to users to be on the lookout before getting in lakes, rivers and reservoirs with foamy, scummy, thick-like pea-green or blue-green paint. Brownish-red mats can also be a sign of a bloom. Authorities say, “when in doubt, stay out.”