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Harmful Algal Blooms & Cyanobacteria

algae on a lake

Most species of algae are not harmful, but sometimes certain types of algae bloom in excessive amounts and can cause severe harm to human health, aquatic ecosystems, as well as local economies. These harmful algal blooms (HABs), usually associated with algae that produce unhealthy toxins, cause problems across the Nation.

Sometimes HABs are referred to as red tides, but this can be misleading since they can be different colors. Also, even though they are classified as bacteria, cyanobacteria exhibit characteristics of algae and are associated with HABs. EPA researchers are looking for ways to eliminate or reduce the negative effects of HABs on human health and the environment.

Harmful Algal Bloom Research: