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EPA Issues Recommendations for Recreational Water Quality Criteria and Swimming Advisories for Cyanotoxins

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EPA Press Office ( )

WASHINGTON —Today, as part of the U.S. Environmental Protection Agency (EPA)’s efforts to better protect Americans’ health when they swim or play near the water this summer, EPA is issuing new recommendations for water quality criteria and swimming advisory values for two cyanotoxins.

“With Memorial Day and summer vacations around the corner, EPA is providing this information to help Americans know when it is safe to swim and play near the water,” said EPA Office of Water Assistant Administrator David Ross. “EPA’s new recommendations will help state and local officials make informed decisions about when to issue local water quality and swimming advisories that are designed to protect the public, especially vulnerable populations like our nation’s children.”

Algal blooms caused by cyanobacteria sometimes produce cyanotoxins at concentrations that can be harmful to people swimming or participating in other activities in or on the water. States can adopt EPA’s recommended cyanotoxin values into their water quality standards or use the values as the basis for issuing a local swimming advisory.

Based on the latest scientific information, EPA has established recommended water concentrations, at or below which protects public health, for the cyanotoxins microcystins (8 micrograms per liter) and cylindrospermopsin (15 micrograms per liter). EPA’s recommendations are protective of all age groups and are based on peer-reviewed and published science.

EPA is also releasing infographics that states and communities can use to communicate basic information about harmful algal blooms (HABs) to the public. The infographics highlight how HABs may affect both people and animals and provide guidance on how to identify and respond to a potential HAB. States, tribes and waterbody managers can download handout- and poster-sized infographic files, along with instructions on how to add local contact information, from EPA’s newly refreshed Cyanobacterial HABs website

EPA will soon release draft technical support materials for public comment that, when final, are intended to help interested states and authorized tribes in implementing these recommended values. Support materials will include information on waterbody monitoring, assessing attainment of water quality standards, listing of impaired water bodies and developing total maximum daily loads under Clean Water Act section 303(d).

For more information about the recommended criteria and swimming advisories visit:

To download EPA’s HABs infographics, visit