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Endangered Species

Assessing Pesticides under the Endangered Species Act

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EPA Responsibilities

When registering a pesticide or reassessing the potential ecological risks from use of a currently registered pesticide, EPA evaluates extensive environmental fate and toxicity data to determine how a pesticide will move through and break down in the environment and whether potential exposure to the pesticide will result in adverse effects to wildlife and vegetation. We routinely assess risks to birds, fish, invertebrates, mammals and plants to determine whether a pesticide may be licensed for use in the United States.

EPA’s pesticide risk assessment and regulatory processes ensure that protections are in place for all populations of non-target species. EPA's current methods for evaluating the risk of pesticide to listed species and designated critical habitat are described in the Overview of the Ecological Risk Assessment Process. However, new methods are being developed as described below.

The National Academy of Science’s Report

In 2011, the EPA and the Departments of Agriculture, Commerce and the Interior requested that the National Research Council of the National Academy of Science convene a committee of independent experts to examine topics pertaining to tools and approaches for assessing the effects of proposed FIFRA actions on endangered and threatened species and their critical habitats. 

The NRC 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.
  • Using geospatial information and datasets in the course of these assessments.

NAS released its report in April 2013 with its recommendationsExit

In November 2013, EPA, the U.S. Fish and Wildlife Service, National Marine Fisheries Service (the Services), and USDA released a white paper containing a summary of their joint interim approaches for assessing risks to listed species from pesticides based on the NAS report recommendations.  These interim approaches:

  • were developed jointly by the agencies in response to the NAS recommendations;
  • reflect a common approach to risk assessment shared by the agencies; and
  • will be implemented jointly as part of a phased iterative process.

In the interim, EPA will continue to rely on the risk assessment procedures described in the Overview of the Ecological Risk Assessment Process to determine whether individuals of a listed species have the potential to be harmed by a pesticide.

EPA is working collaboratively with the Services and USDA to further develop the scientific methods described in the interim approaches. Once fully vetted, these methods will be implemented in a phased and iterative approach to evaluate the potential risks to federally listed threatened and endangered species and their designated critical habitat from registered uses of pesticides. 

Our conclusion regarding the potential risks a pesticide may pose to a listed species and any designated critical habitat for the species, after conducting a thorough ecological risk assessment, results in an "effects determination," also referred to as a "biological evaluation (BE)."

More information on the NAS report process.

Learn about setting priorities for endangered species assessments.

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Effects Determinations

The result of an assessment to determine potential effects of a pesticide’s registration to a listed species will result in one of two determinations:

  • The pesticide’s registered use will have "no effect" on the species or designated critical habitat,
  • The pesticide’s registered use "may affect" the species or designated critical habitat.

If EPA determines the pesticide "may affect" the species it refines its assessment to determine whether the pesticide’s use:

  • "may affect, but is not likely to adversely affect" the species or designated critical habitat; or
  • "may affect and is likely to adversely affect" the species or designated critical habitat. 

A determination that the pesticide "may affect, but is not likely to adversely affect," is made when the effects on the listed species and/or designated critical habitat are expected to be discountable, or insignificant, or completely beneficial. The Services have discussed these terms in guidance as including effects:

  • are extremely unlikely to occur, which cannot be evaluated (discountable);
  • would never reach a scale where take would occur (insignificant); or
  • are wholly beneficial (completely beneficial). 

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Consulting with the Services

Informal Consultation

If EPA determines that a pesticide will have "no effect" on a listed species, no further action is required relative to the pesticide’s registration, label or use instructions. If EPA determines that a pesticide’s use "may affect, but is not likely to adversely affect" a listed species, EPA will engage the Services in a process called informal consultation. The result of this process is typically a letter in which the Services concur or non-concur with EPA’s determination.

Formal Consultation

If the Services do not concur with EPA’s determination that a pesticide’s registered use is "not likely to adversely affect" a species or if EPA determines that the pesticide "may affect and is likely to adversely affect" a listed species, it will engage the Services in a process called formal consultation.  

During formal consultation (under 50 CFR Part 402, Subpart B), EPA provides the Services with its detailed assessment of potential risks and its effects determination. The Services review that information and consider it in light of the status and needs of the particular species potentially affected. The Services then provide EPA with a Biological Opinion, a document providing the Services' assessment and recommendations for steps that EPA should take, if any, to reduce or eliminate potential risk to the species.  

The Services’ Biological Opinion provides the Services’ view of whether the pesticide’s registered use is likely to jeopardize the continued existence of the species and, if so, describes alternatives to avoid jeopardy. The Services also authorize any "take" (unintended injury or killing of individual listed species) that would otherwise be prohibited, as long as measures to minimize take are implemented.

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Implementing Measures to Protect Listed Species

After EPA’s risk assessment or formal consultation with the Services, if  EPA determines that a pesticide’s registration, label, or use instructions should be altered to ensure use of a pesticide will not take or jeopardize the continued existence of a listed species, EPA may require changes to the use conditions specified on the label of the product. When such changes are necessary only in specific geographic areas rather than nationwide to ensure protection of the listed species, EPA implements these changes through geographically-specific Endangered Species Protection Bulletins.

Read more about Endangered Species Protection Bulletins.

Enhancing Stakeholder Interaction

EPA and its federal partners are committed to enhancing opportunities for stakeholder input during pesticide registration reviews and endangered species consultations. View a paper developed by EPA and our federal partners in the docket (EPA-HQ-OPP-2012-0442) at www.regulations.gov, along with public comments received from a variety of stakeholders. We and our partners will use the measures included in the paper in future efforts to protect endangered and threatened species.

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