The Oklahoma Department of Environmental Quality (DEQ) and the Grand River Dam Authority (GRDA) confirmed the presence of Blue Green Algae (BGA) in Grand Lake. GRDA and ODEQ want the public and lake users to remain careful, vigilant and aware where BGA has been confirmed and they continue to test and monitor lake waters. People, pets, and livestock should not be swimming in or drinking the water in affected water sources.

Blue Green Algae (BGA) is a cyanobacterium. BGA are microscopic organisms that live in all types of water. These bacteria have photosynthetic capabilities. Nutrients, especially phosphorus and nitrogen, or manure (and sewage) runoff leads to eutrophication and accelerated algae growth. Blue-green algae grow quickly, or bloom, when the water is warm, slow-moving, and full of nutrients. Algae usually bloom during the summer and fall. However, they can bloom any time during the year. Most of the problems in Oklahoma do occur in the summer months, but some varieties actually prefer cold water and have occurred in the winter. When a bloom occurs, scum might form on the water’s surface. Blooms can be many different colors, from green or blue to red or brown. As the bloom dies off, you might smell an odor that is similar to rotting plants.

Sometimes, blue-green algae produce toxins, such as microcystins. The toxins can be present in the algae or in the water. Topical (skin) exposure can cause dermatitis. Low oral doses can cause vomiting and diarrhea. Consumption of higher amounts of the toxins associated with this algae can affect the liver and neurological tissue and can cause sudden death. The term “Fast Death Factor” comes from finding the animals dead in the water or near it. The wind can actually blow the algae to one side, concentrating it, often looking like blue paint. The toxin is released when the algae blooms.

Dogs generally have more severe symptoms than people, including collapse and sudden death after swallowing the contaminated water while swimming or after licking algae from their fur. There are no known antidotes to these toxins. Medical treatment is basically supportive care.

If you suspect a water source contains toxic blue green algae, pets, livestock and people should stay away until the bloom dissipates or the water has been treated with copper sulfate (as per label instructions). This may take several weeks since the copper sulfate also causes death of the algae and release of toxins. The algae can be identified at the Oklahoma Animal Disease Diagnostic Laboratory by sending a pint container of suspect water. The blooms will deteriorate, so fresh samples are best.

To report a blue-green algae bloom or related health event:

Call the Oklahoma Department of Environmental Quality Hotline number: 1-800-522-0206.

For more information:

• http// or

• Call the National Center for Environmental Health Harmful Algae Blooms Program (HABISS) Centers for Disease Control and Prevention: 866-556-0544

• Algae Identification: Oklahoma Animal Disease Diagnostic Laboratory (405) 744-6623

Sandra Morgan, DVM, Veterinary Toxicologist

Oklahoma Animal Disease Diagnostic Laboratory

National Center for Environmental Health Division of Environmental Hazards and Health Effects