Blue-Green Algae

The Wisconsin Department of Health Services states "Many species of algae are found in Wisconsin lakes and rivers. Algae act like other plants and convert sunlight into energy, forming the base of a lake’s food chain. Algae are eaten by zooplankton, which are in turn eaten by small fish, then larger fish, and eventually the larger fish are eaten by birds, shore animals, and people. True algae are a vital part of lake systems, however, blue-green algae are not true algae. Blue-green algae are photosynthetic bacteria known as cyanobacteria which can cause illness and death in humans and animals. While blue-green algae can convert sunlight into energy, they are not an important a part of the food chain because most organisms prefer not to eat them.

Blue-green algae are a natural part of lake ecosystems and algal blooms have occurred for many centuries. While scientists are learning more and more about blue-green algae, researchers are only beginning to understand the health risk blue-green algae pose to humans and animals.

Health Risks from Blue-Green Algae

The toxins that the algae produce can affect your health in different ways.  People react differently to the toxins depending on a number of different factors.  Algal toxins can cause people to have respiratory symptoms such as coughing, congestion, sore throat, and difficulty breathing.  Others may experience eye irritation, itchy and red skin, and even hives.  In more serious cases it can lead to vomiting, diarrhea, and severe abdominal pain.

If you think you have blue-green algae related illnesses, contact your doctor and report the incident to the Wisconsin Harmful Algal Blooms Program at 608-266-1120.

If you think that the body of water you are on has an algae bloom, use common sense.

• Do not boat, swim, or ski through algal scum or blooms

• Do not fish where algal scum is present

• Shower off with soap and water after swimming in lakes and river ways

• Do not let your dog drink water where an algae bloom is present

• Rinse your dog off with clean water after swimming