EPA issues health advisories to protect public from algal toxins in drinking water

The Environmental Protection Agency issued health advisories that states and utilities can use to protect the public from elevated levels of algal toxins in drinking water.

WASHINGTON, DC, May 6, 2015 -- Today, the Environmental Protection Agency (EPA) issued health advisories that states and utilities can use to protect the public from elevated levels of algal toxins in drinking water. The Agency has determined algal toxin levels in tap water that are protective of human health based on the best available science. EPA is also recommending how utilities can monitor and treat drinking water for algal toxins and notify the public if drinking water exceeds protective levels.

EPA will issue the final documents containing the health advisory values, recommended monitoring and treatment approaches, and all supporting technical information before summer, which is prime season for algal blooms because of warmer temperatures. Last August, a harmful algal bloom in Lake Erie, for example, left half-a-million residents of Toledo without drinking water for two days (see "Toledo water resources contaminated by Lake Erie algal toxin"). EPA estimates that between 30 and 48 million people use drinking water from lakes and reservoirs that may be vulnerable to algal toxin contamination.

"Nutrient pollution and harmful algal blooms are among America's most serious and growing environmental challenges," said EPA Administrator Gina McCarthy. "EPA has released health advisory values on algal toxins based on the best available science to ensure the safety of America's drinking water. We will work closely with our partners at the state and local levels on monitoring, treating and communicating about the toxins, as well as addressing the sources of nutrients that fuel these harmful algal blooms."

Health advisories are not regulations but provide technical guidance to help state and local officials and managers of water systems protect public health. They identify concentrations of contaminants above which adverse health effects are possible and provide testing methods and treatment techniques. The values for toxins recommend 0.3 micrograms per liter for microcystin and 0.7 micrograms per liter for cylindrospermopsin as levels not to be exceeded in drinking water for children younger than school age. For all other ages, the values for drinking water are 1.6 micrograms per liter for microcystin and 3.0 micrograms per liter for cylindrospermopsin.

EPA will seek input from stakeholders on the recommended actions and other information the Agency can provide to best support states and utilities in addressing algal toxins in drinking water. Based on input, the Agency may provide additional technical support documents before the peak of algal bloom season. EPA worked with Health Canada to develop the health advisories. The World Health Organization has indicated it will use the health advisories to reevaluate global recommendations for levels of algal toxins. As the science on the health impacts of algal toxins continues to improve, the Agency will track developments and update recommendations as appropriate.

See also:

"Congress Mulls Legislation to Address Algal Toxins"

"AWWA, WRF release guide for utility managers to detect, control cyanotoxins"

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