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.
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.
- Invited Expert Meeting on Revising U.S. EPA's Guidelines for Deriving Aquatic Life Criteria (September 2015)
Proceedings from EPA's Frequency and Duration Experts Workshop
EPA’s Office of Science and Technology convened a Frequency and Duration Experts Workshop on September 11–12, 2019 in Arlington, Virginia. Invited technical experts representing academic, state, federal, and international institutions met and were tasked with discussing the science of frequency and duration of exposure as related to Aquatic Life Ambient Water Quality Criteria for toxic chemicals. The purpose of the workshop was not to reach consensus on specific topics, but instead to gather and discuss the currently-available science about frequency and duration of Aquatic Life Criteria for toxic chemicals for the protection of aquatic communities. Presentations and discussions during this workshop are summarized in the meeting proceedings and will be considered by EPA when evaluating the state of the science for development of Aquatic Life Water Quality Criteria.
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. Bioavailability models and criteria developed for each metal through the CRADA will be open for external peer review and public comment.
- Summary of the Cooperative Research and Development Agreement for Aquatic Life Bioavailability Modeling for Metals (pdf)
- Workplan of the Cooperative Research and Development Agreement for Aquatic Life Bioavailability Modeling for Metals (pdf)
- Progress Update for CRADA for Aquatic Life Bioavailability Modeling for Metals – Year 1 (2018)
- Metals CRADA Phase 1 Report
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.
Metals Aquatic Life Criteria and Chemistry Map (MetALiCC-MAP)
The Metals Aquatic Life Criteria and Chemistry Map, or MetALiCC-MAP (v 1.0) is a tool to support states, tribes and stakeholders in determining protective aquatic life ambient water quality criteria for metals. Several metals aquatic life criteria require water chemistry data as inputs (e.g., pH, water hardness, ions and dissolved organic carbon) to calculate criteria.
This interactive web-available Geographic Information Systems (GIS)-based mapping tool provides water chemistry information and calculates aquatic life criteria for aluminum and copper. Information is provided for the entire conterminous United States. States, tribes, and other water quality stakeholders can use this tool to develop aquatic life criteria that reflect their spatial scale of interest – from a very small area like a specific site or particular stream segment to a very large area that spans a state or multiple states. This tool may be especially useful when water chemistry data need to calculate criteria are limited or not available.
To develop this tool EPA compiled and analyzed and applied publicly-available national water chemistry data presented in the US Geological Survey (USGS) National Water Information System (NWIS) database.