EPA: Harmful Algal Blooms


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Interagency Report Aims to Reduce Impacts of Freshwater Harmful Algal Blooms

August 4th, 2008

The National Oceanic and Atmospheric Administration, the Environmental Protection Agency, and the National Science and Technology Council released an interagency report today that presents a plan for minimizing the impacts of freshwater harmful algal blooms in the United States.

"Freshwater HABs pose serious threats to human and ecological health. This report assesses the state of knowledge about freshwater HABs in the U.S. and sets research priorities to improve our ability to minimize or even prevent impacts of these events," said retired Navy Vice Admiral Conrad C. Lautenbacher, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator.

"The central importance of this report is that this is the first comprehensive look at harmful algal blooms in U.S. freshwaters," says Paul Sandifer, Ph.D., a former member of the U.S. Commission on Ocean Policy, current senior scientist with NOAA's Oceans and Human Health Initiative and Co-Chair of the Interagency Working Group on Harmful Algal Blooms, Hypoxia and Human Health that produced the report. "Freshwater algal blooms are equally as important and problematic as those found in marine waters. They can affect drinking water for the millions of people across the country who rely on surface fresh water supplies such as the Great Lakes."

The report, Scientific Assessment of Freshwater Harmful Algal Blooms, presents a plan to minimize health and economic impacts of freshwater HABs and to ensure the resilience of the nation’s freshwater ecosystems.  Priorities for federal programs include:

Freshwater HABs are caused by algae that produce toxins or accumulate excessive biomass. Recent impacts in the U.S. have included foul taste and odor problems in drinking water sources and farm-raised fish, domestic and wild animal deaths, and reduced recreational opportunities due to noxious or toxic blooms. Human illness has also been associated with large toxic blooms in recreational waters.

The report notes that a majority of states have now experienced freshwater HABs. Human activities, such as nutrient pollution, alteration of water flow, and introduction of invasive species, are thought to contribute to some of these increases.

The report is the second of five mandated by Congress in the 2004 reauthorization of the Harmful Algal Bloom and Hypoxia Research and Control Act (HABHRCA) and is the only one focused on freshwater HABs. The Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health (IWG-4H) was tasked, under the President's Ocean Action Plan by the Joint Subcommittee on Ocean Science and Technology as the coordinating body to fulfill HABHRCA reporting requirements, including this assessment.

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