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Aquatic Life Criteria and Methods for Toxics

EPA bases aquatic life criteria on how much of a chemical can be present in surface water before it is likely to harm plant and animal life. EPA designs aquatic life criteria to protect both freshwater and saltwater organisms from short-term and long-term exposure.

Criteria and Methods Documents:

Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and their Uses

EPA's 1985 Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses (the Guidelines) describe a process that uses information form many areas of aquatic toxicology to deriving national criteria for the protection of aquatic ecosystems.

EPA Activities Related to Revising the Aquatic Life Guidelines

The existing Guidelines for Deriving Water Quality Criteria for the Protection of Aquatic Life and Their Uses have not been updated since 1985. Although based on science of that time, the past 30 years have witnessed substantial scientific advancement in aquatic toxicology, aquatic biology, fate, transport, and effects modeling, and ecological risk assessment. Such advancements, coupled with increasing complexity of water quality impairment issues requires criteria derivation approaches beyond the existing Guidelines methods.

EPA has begun the process of revising the existing Guidelines used to derive National Ambient Water Quality Criteria for the protection of aquatic life. EPA will consider new and alternative methods for deriving aquatic life criteria to inform revision of EPA’s existing guidance using the newest most appropriate science available.

Request for Nominations of Experts to Augment the Science Advisory Board Ecological Processes and Effects Committee to Provide Advice on Methods for Deriving Water Quality Criteria for the Protection of Aquatic Life - August 2016

EPA, SAB Staff Office requested public nominations of scientific experts to augment the SAB Ecological Processes and Effects Committee (EPEC) for review of a draft EPA document entitled “Scope and Approach for Revising EPA's Guidelines for Deriving National Water Quality Criteria to Protect Aquatic Life.” The comment period ended September 20, 2016.

Cooperative Research and Development Agreement for Aquatic Life Bioavailability Modeling for Metals

EPA has signed a Cooperative Research and Development Agreement (CRADA) with eight metals associations in order to leverage the knowledge and resources of scientists inside and outside of the agency to better protect aquatic life. Current science demonstrates that water chemistry parameters (e.g., pH, dissolved organic carbon, and hardness) can affect the toxicity of metals by affecting the bioavailability of metals in the water to aquatic species. Through the CRADA, EPA will work collaboratively with the metals associations to develop a common modeling approach that can predict the bioavailability and toxicity of metals. Using the resulting peer-reviewed modeling approach, EPA plans to develop updated Aquatic Life Ambient Water Quality Criteria for metals to better support states, territories and tribes with criteria that reflect the most current science and are easier to implement than current approaches. All approaches and products developed through the CRADA will be open for external peer review and public comment.

Common Effects Methodology for Pesticides

EPA's Office of Pesticide Programs (OPP) and the Office of Water (OW) assess the effects of pesticides on aquatic ecosystems using approaches that afford a high degree of protection for aquatic life and that were developed with high quality data using rigorously peer-reviewed assessment methodologies. The Agency anticipates merging these approaches toward a common effects methodology.

Contaminants of Emerging Concern Including Pharmaceuticals and Personal Care Products

It is important for EPA to be able to evaluate the potential impact of contaminants of emerging concern (CECs), including pharmaceuticals and personal care products PPCPs, on aquatic life and have an approach for determining protective levels for aquatic organisms. CECs and PPCPs are increasingly being detected at low levels in surface water, and there is concern that these compounds may have an impact on aquatic life.

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