BISMARCK, N.D. – The North Dakota Department of Environmental Quality reminds residents that hot weather and accumulated nutrients can lead to blue-green algae (cyanobacteria) blooms in water bodies across the state. Blue-green algae can cause Harmful Algal Blooms, producing toxins in the water called cyanotoxins. Environmental Quality responds to reported blooms across the state and tests water for toxins. If toxins are at an unsafe level, Environmental Quality issues public advisories and warnings.

People that swallow or come into contact with water containing cyanotoxins can become sick with diarrhea and vomiting; or experience numb lips, tingling fingers and toes, dizziness, rashes, hives and skin blisters. Pets and livestock may also suffer adverse health effects, including death. There are no known antidotes for the cyanotoxins produced by blue-green algae. Children and pets are at a higher risk than adults for illness because of their smaller size.

Blue-green algae can look like grass clippings floating in the water, clumps/puffballs or green cottage cheese. It can also make the water appear like spilled green paint or green pea soup.