Fast Facts About Blue-Green Algae

Blue-green algae are naturally found in many lakes, rivers, and ponds. Sometimes they grow very quickly and form harmful algal blooms (HABs) that can produce dangerous toxins. These blooms often make the water look bright green or create a thick layer that looks like green paint. Contact with these toxins can cause skin rashes, stomach problems, and, in some cases, liver damage. They can also make pets and wildlife sick.

 

If you see water that looks like it has a blue-green algae bloom, stay out of it. Do not swim, wade, or let your children or pets play in the water. Do not drink or cook with the water because boiling and most home water filters will not remove the toxins. If you accidentally come into contact with the water, wash your skin with clean water right away. See a healthcare provider if you feel sick or develop a rash and contact your veterinarian if your pet becomes ill.

 

If you catch fish or crabs from water with a blue-green algae bloom, remove the fish's skin, fat, and internal organs before cooking. For crabs, throw away the mustard (hepatopancreas) before eating.

 

To report a suspected algae bloom or fish kill, call the Maryland Department of Natural Resources at (866) 633-4686.

 

For questions about harmful algal blooms, contact the Maryland Department of the Environment at (443) 482-2731 or (443) 482-2710.