Pesticide Program Update: EPA Seeking Public Nominations for Experts to Serve as Ad Hoc Reviewers for Analysis of Atrazine Ecological Risks

This original announcement was published by the EPA on March 25, 2023. Click here for more information!


The U.S. Environmental Protection Agency (EPA) is seeking public nominations of scientific and technical experts for consideration to serve as ad hoc reviewers assisting the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP) with the review of the Agency’s analysis and assessment of ecological risk from atrazine use. EPA is also announcing a three-day public virtual meeting on August 22-24, 2023, starting at 10:00 a.m. to approximately 5:00 p.m. EDT on Examination of Microcosm/Mesocosm Studies for Evaluating the Effects of Atrazine on Aquatic Plant Communities.  

Nominations must be submitted on or before April 24, 2023. These nominations will be used to assist the Agency in selecting approximately 8-12 ad hoc reviewers to assist the FIFRA SAP with their review. The review will take place during the August public meeting. Registration information for the meeting will be announced on the FIFRA SAP website in July.  

Individuals nominated for this FIFRA SAP peer review should have expertise in one or more of the following areas: aquatic plant community ecology; aquatic community ecology; plant community ecology; algae community ecology; aquatic plant ecology; aquatic toxicity; ecotoxicity; plant toxicity; algae toxicity; and/or mesocosm experiments. Nominees should be scientists with sufficient professional qualifications, including training and experience, to provide expert comments on the scientific issues for this review.

Prospective candidates for service on the FIFRA SAP will be asked to submit confidential financial information which shall fully disclose, among other financial interests, the candidate’s employment, stocks and bonds, testimonies, and where applicable, sources of research support. EPA will evaluate the candidates’ financial disclosure information to assess whether there are financial conflicts of interest, appearance of a loss of impartiality, or any prior involvement with the development of the documents under consideration (including previous scientific peer review) before the candidate is considered further for selection and service on the FIFRA SAP. 

Nominations must be submitted to the Designated Federal Official (DFO), Tamue Gibson, MS, via email at gibson.tamue@epa.govDo not email any information you consider to be Confidential Business Information or other information whose disclosure is restricted by statute.  

For additional information, please contact the DFO or view the Federal Register Notice in docket EPA-HQ-OPP-2023-0154.

The FIFRA SAP serves as one of the primary scientific peer review mechanisms of EPA’s Office of Chemical Safety and Pollution Prevention and is structured to provide independent scientific advice, information and recommendations to the EPA Administrator on pesticides and pesticide-related issues regarding the impact of regulatory actions on human health and the environment. 

Pesticide Program Update: EPA Posts Draft Biological Opinion for Carbaryl and Methomyl for Public Comment

This original announcement was published by the EPA on March 16, 2023. Click here for more information.


Today, the U.S. Environmental Protection Agency (EPA) is posting and seeking public comment on the National Marine Fisheries Service’s (NMFS) draft biological opinion for the insecticides carbaryl and methomyl. Carbaryl and methomyl are insecticides used on a variety of cropsincluding field vegetables and orchard crops.   

Under the Endangered Species Act (ESA), EPA must ensure that its actions, including many pesticide registration actions, do not jeopardize federally listed endangered or threatened species, or adversely modify their designated critical habitats. When EPA determines in a biological evaluation that use of a pesticide product may affect these species or critical habitats, EPA must initiate formal consultation with NMFS, the U.S. Fish and Wildlife Service (FWS), or both (the Services). In response, the Service(s) may develop a biological opinion that determines whether the pesticide will jeopardize listed species or adversely modify critical habitats.  

In March 2021, EPA completed its final biological evaluations for carbaryl and methomyl. EPA’s biological evaluations made “likely to adversely affect” determinations for 1,640 listed species and 736 designated critical habitats for carbaryl and 1,098 listed species and 736 designated critical habitats for methomyl. A “likely to adversely affect” (LAA) determination means that EPA reasonably expects that at least one individual animal or plant of any listed species may be exposed to these pesticides at a sufficient level to have an adverse effect. This is the case even if a listed species is almost recovered to a point where it may no longer need to be listed. 

EPA initiated formal consultation with the Services upon completing these biological evaluations and, in response, NMFS has developed a draft biological opinion for carbaryl and methomyl.  

Biological opinion and next steps 

The draft biological opinion includes NMFS’s determinations that, under the ESA, use of carbaryl and methomyl is likely to jeopardize some listed species and adversely modify their critical habitats when used as registered. The draft biological opinion contains measures to avoid jeopardy and adverse modification, and to minimize “take,” which is incidental harm of listed species.  

In its draft biological opinion, NMFS evaluated the effects of the use of pesticide products containing carbaryl and methomyl and determined that carbaryl is likely to jeopardize 37 listed species and adversely modify 36 critical habitats. Methomyl is likely to jeopardize 30 listed species and adversely modify 29 critical habitats. These findings cover only NMFS species. FWS will issue its own biological opinion addressing the listed species under their purview.  

The draft biological opinion describes measures to avoid jeopardy, including a flexible list of chemical-specific measures to reduce loading of pesticides into aquatic habitats to protect them from adverse effects of pesticide exposure. It also includes measures to minimize take and impacts to critical habitats, such as the development of ESA educational materials, reporting of label compliance monitoring, and inclusion of label information about ecological incident reporting. 

EPA and NMFS are particularly interested in comments on the draft biological opinion regarding:  

  • additional risk reduction options beyond those described in the biological opinion; 
  • the general feasibility of drift reduction measures based on wind direction; and 
  • runoff and/or spray drift reduction technologies. 

After the 60-day public comment period, EPA will provide NMFS with the comments received and a summary of the comments for consideration before it finalizes the biological opinion. EPA will implement the final biological opinion.   

The biological opinion is available for public comment in docket EPA-HQ-OPP-2023-0144. 

Biological Opinions Available for Public Comment and Links to Final Opinions

EPA Announces Accelerated Action on Four Organophosphate Pesticides Based on Updated Exposure Assessments

This original announcement was published by the EPA on March 15, 2023. Click here for more information.


Today, the U.S. Environmental Protection Agency (EPA) is announcing an effort to expedite protections on some high-risk uses of four organophosphate pesticides. The Agency is releasing the updated occupational and non-occupational spray drift exposure risk assessments for these four pesticides – diazinon, ethoprop, tribufos and phosmet – several years ahead of the scheduled completion of EPA’s work on these chemicals in order to seek early mitigation prior to completing the standard registration review process.

“The science is clear: some uses of these four pesticides pose a serious health risk to the people that are exposed to them,” said Michal Freedhoff, Assistant Administrator for the Office of Chemical Safety and Pollution Prevention. “That’s why we’re taking early action now. While we know there’s still a lot of work to finish our review of these pesticides, today’s announcement helps deliver on our promise to protect farmworkers and uphold our commitment to environmental justice.”

Diazinon, ethoprop, tribufos and phosmet are part of the group of pesticides known as organophosphates. These pesticides are used in both agricultural (e.g., fruit and nut trees, vegetables and herbs, cotton) and non-agricultural settings for a range of purposes. Diazinon and phosmet controls insects, ethoprop controls worms and other soil pests, and tribufos defoliates cotton prior to harvest. These pesticides are currently undergoing registration review, a process that requires EPA to reevaluate pesticides every 15 years to ensure that as the ability to assess risk evolves and as policies and practices change, pesticides continue to meet the statutory standard of causing no unreasonable adverse effects on human health or the environment.

As part of the registration review process, EPA assessed the potential risks to people who mix, load, and apply the four pesticides, farmworkers who work with crops that have been treated with these pesticides, and bystanders who are potentially exposed to spray drift, including families living in agricultural communities.

The Agency identified the following potential risks for each pesticide:

  • The diazinon assessment identified potential risks to workers who mix, load, and apply the pesticide, and to bystanders (including farmworkers) who could be exposed to spray drift.
  • The ethoprop assessment identified potential risks to workers who mix, load, and apply the pesticide, and to bystanders (including farmworkers) who could be exposed to spray drift.
  • The phosmet assessment identified potential risks to workers who mix, load, and apply the pesticide, workers conducting certain post-application activities (e.g., weeding, hand harvesting, or workers re-entering treated areas), and bystanders (including farmworkers) who may be exposed to spray drift.
  • The tribufos assessment identified potential risks to workers who mix, load, and apply the pesticide, and to bystanders (including farmworkers) who may be exposed to spray drift.

Although registration review for these pesticides was not scheduled to be completed until 2025-2026, after recognizing that several of uses of these four pesticides present significant human health risks, EPA is taking accelerated and early action to address these risks. This will allow the Agency to put important protections in place quickly for some high-risk uses of these pesticides, while allowing time to work through the complicated scientific issues that need to be addressed before completing registration review.

EPA is currently meeting with the technical registrants of the four pesticides about early risk mitigation. The types of mitigation under consideration include cancellation of uses and formulation types, prohibition of application methods, increased personal protective equipment for pesticide handlers, spray drift requirements, and new restrictions on when workers can reenter treated fields and perform harvesting and other types of post-application activities. The Agency is asking the registrants to submit label amendments that reflect the necessary risk mitigation measures for each of these four organophosphates and is prepared to expedite label reviews in order to implement the protections as quickly as possible.

The updated exposure risk assessments are now available in the registration review dockets, EPA-HQ-OPP-2008-0351 (diazinon), EPA-HQ-OPP-2008-0560 (ethoprop), EPA-HQ-OPP-2008-0883 (tribufos) and EPA-HQ-OPP-2009-0316 (phosmet) at Given the expedited nature of this effort, the Agency is not taking comment on these assessments. Stakeholders will have an opportunity to comment on the four occupational and non-occupational spray drift risk assessments when the cases progress through the next step of registration review with the proposed interim decision, which will include the full updated human health risk assessment for each. EPA expects to issue the proposed interim decisions in fiscal year 2025 (tribufos) and fiscal year 2026 (ethoprop, diazinon and phosmet).

EPA Finalizes Updates to List of Pests of Significant Health Importance

This original announcement was published by the EPA on March 1, 2023. Click here for more information.


The U.S. Environmental Protection Agency has released an updated list of pests of significant health importance. The list identifies the pests that EPA, the Centers for Disease Control and Prevention (CDC), and the U.S. Department of Agriculture (USDA) currently consider to be of significant public health importance.  

The list of pests serves as a useful tool for private and public organizations, including local or state governments, departments of public health, pesticide registrants, and non-governmental organizations when making decisions and planning for future public health actions. Federal law requires that EPA develop and implement programs to improve and facilitate the safe and necessary use of chemical, biological, and other methods to combat and control such pests of public health importance.  

Since this list’s original publication in 2002, EPA, CDC, and USDA have identified new vector-borne diseases and pests that were previously considered benign or nuisance pests, but have since been shown to adversely impact public health. The final Pesticide Registration Notice (PRN) adds several new pests (e.g., brown dog tick) and public health impacts (e.g., Zika fever and coronaviruses like SARS-CoV-2). Other pests have been renamed, grouped with similar species or removed altogether. 

Read the final PRN in docket EPA-HQ-OPP-2020-0260 at