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Endangered Species

Implementing NAS Report Recommendations on Risk Assessment Methodology for Endangered and Threatened Species

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In 2011, EPA and the Departments of Agriculture, Commerce and the Interior requested that the National Research Council of the National Academy of Sciences (NAS) convene a committee of independent experts to examine topics pertaining to tools and approaches for assessing the effects of proposed Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) actions on listed species and their critical habitats.

The National Research Council was asked to consider a range of issues, including:

  • identifying best-available scientific data and information;
  • considering sub-lethal, indirect and cumulative effects;
  • assessing the effects of chemical mixtures and inert ingredients;
  • using models to assist in analyzing the effects of pesticide use;
  • incorporating uncertainties into the evaluations effectively; and
  • using geospatial information and datasets during these assessments.

NAS released its report in April 2013 with its recommendations. Read the NAS report. Exit EPA is using an iterative process for developing methods and conducting national-level biological evaluations (BEs). In this approach, EPA has developed methods to inform and advance the development of national- level BEs. The first approach was developed in 2015 and is referred to as the Interim Method, which was applied to the first three national-level BEs (for chlorpyrifos, diazinon and malathion).

The document describing the Interim Method was general, and the first three pilot BEs included details regarding application of the Interim Method to those BEs.

EPA Releases Revised Method

Since the release of the NAS report, EPA, U.S. Fish and Wildlife Service, National Marine Fisheries Service, and the U.S. Department of Agriculture (referred to as “the agencies”) have been working together to develop and improve methods for assessing risks to listed species. In March 2020, EPA released the Revised Method for National Level Listed Species Biological Evaluations of Conventional Pesticides. The Revised Method updates the Interim Method developed in 2015.

EPA used the Revised Method to conduct the draft BEs for carbaryl, methomyl, atrazine, propazine,  simazine, and glyphosate.

 The information provided for each chemical is on a separate page at the following links: 

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Background on the Draft Revised Method

In May 2019, EPA released the draft Revised Method used to evaluate the impacts pesticides could have on listed species.  Listed species include federally listed endangered and threatened species, as well as experimental populations and those species that are proposed and candidates for listing. EPA worked closely with its federal partners to develop the draft Revised Method and received public comment on it through August 2019. The proposed draft Revised Method was an important step in further refining the Interim Method developed in 2015.

EPA held a public meeting on June 10, 2019, to present the proposed draft Revised Method and to allow attendees the opportunity to ask clarifying questions and provide comments. As a result of several stakeholder requests, EPA held an extended comment period on the proposed draft Revised Method in docket #EPA-HQ-OPP-2019-0185 at, from May 16, 2019 through August 15, 2019. EPA also formally consulted with Tribes on the draft Revised Method. The Response to Comment document (PDF) (65 pp, 645 K, About PDF) that addresses public comments on May 2019 proposed draft Revised Method is available.

The June 10 public meeting was part of the federal government’s coordinated effort to improve the Endangered Species Act (ESA) process that is used when pesticides are registered. The 2018 Farm Bill established an interagency ESA working group whose task was to provide recommendations to the agencies' leadership on improving the ESA consultation process for pesticides. Input from the public meeting and the public comment period on the draft Revised Method was part of this process.

EPA evaluated public input and met with the US Fish and Wildlife Service, National Marine Fisheries Service, and US Department of Agriculture to discuss the comments from the public and additional input from the agencies to inform the updated Revised Method released in March 2020.

Interim Method

The Revised Method provides updates to the Interim Approaches for Pesticide Endangered Species Act Assessments based on National Academy of Sciences Report Recommendations. To develop the Interim Method, the agencies worked together to develop shared scientific approaches that reflect NAS’s advice.

The Interim Method was used by EPA to finalize BEs for the three pilot chemicals: chlorpyrifos, diazinon and malathion in 2017. A Response to Comment document (PDF) (20 pp, 977 K, About PDF) that addresses public comments submitted in response to the 2016 draft BEs is also available.

The information provided for each pesticide will be on a separate page:

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