EPA releases guidance on cyanotoxins
The U.S. Environmental Protection Agency (EPA) has issued final Recommended Recreational Ambient Water Quality Criteria or Swimming Advisories for two Cyanotoxins, Microcystins and Cylindrospermopsin. EPA has identified recommended concentrations of these cyanotoxins at or below which human health is protected while swimming or participating in other recreational activities in and on the water. States, territories, and authorized tribes can consider adopting these recommended criteria into their water quality standards and using them for Clean Water Act purposes. Alternatively, they can use these same values as the basis of swimming advisories for public notification purposes at recreational waters. The recommended criteria or swimming advisories are based on peer-reviewed, published science and methods.
EPA is also providing information on the latest scientific knowledge about human health effects from exposure to cyanobacteria, discussion of other governmental guidelines for recreational waters, and incidents involving exposure of pets and other animals to cyanotoxins. More information on these recommendations can be found at
EPA is publishing the recommendations for microcystins and cylindrospermopsin, two of the toxins associated with cyanobacterial HABs, under Clean Water Act section 304(a). Learn more about cyanobacterial HABs and how the EPA, states, territories and tribes are working to address them on the newly redesigned EPA Cyanobacterial HABs website. EPA updated and reorganized its online information about
cyanobacterial harmful algal blooms (CyanoHABs) in water bodies, creating a new website dedicated to scientific information, EPA tools, and collaborative work on cyanoHABs in U.S. waters.
On the updated website, EPA has also published new infographics that state and local governments can use to communicate basic information about HABs to the public. The infographics highlight how a HAB may affect both people and animals, and provide information concerning how to identify and respond to a potential bloom. Downloadable and printable versions of the infographics are available at
this link; one as a more detailed poster for display and another as an abbreviated handout. State, tribal and local governments may also customize the infographics by adding their logo and website address or telephone number.