Now Available: Registration for upcoming IRIS Public Science Meeting (November 2021)

This original announcement was published by the EPA on September 30, 2021. Click here to register.


The U.S. Environmental Protection Agency’s (EPA) Health and Environmental Risk Assessment (HERA) National Research Program is announcing a virtual IRIS Public Science Meeting for November 9, 2021. The Integrated Risk Information System (IRIS) Program is convening the previously postponed IRIS Public Science Meeting to discuss the IRIS Assessment Plan associated with the unsuspended naphthalene assessment.

Should you wish to attend the meeting and/or provide oral public comment, register here. Program materials, including the assessment plan, can be found on the Public Science Meeting website. Interested stakeholders may view the public comment received on the naphthalene IAP by visiting Regulations.Gov (Docket no. EPA-HQ-ORD-2014-0527). While IRIS assessments are not associated with proposed rulemaking, serves as both an internal portal to facilitate public comment and as a document repository for Federal government agencies.

Call for Nominations — Review of EPA’s 2021 Draft IRIS Formaldehyde Assessment

EPA’s HERA National Research Program is highlighting that an ad hoc committee of the National Academies of Sciences, Engineering, and Medicine (NAS) will provide the Environmental Protection Agency (EPA) with a review of EPA’s 2021 draft IRIS formaldehyde assessment. An ad hoc committee will assess whether the draft assessment adequately and transparently evaluated the scientific literature, used appropriate methods to synthesize the current state-of-the science, and presented conclusions regarding the hazard identification analysis and dose-response analysis of formaldehyde that are supported by the scientific evidence. The committee will not conduct its own hazard assessment of formaldehyde, nor will the committee address broader aspects of the IRIS Program.

Nominations for committee members and/or reviewers for this study are due by October 15, 2021. For more information regarding this peer review, visit the NAS website.

Now Available: Draft Supplement to the 2019 Integrated Science Assessment for Particulate Matter (PM ISA Supplement)

This original announcement was published by the EPA on September 30, 2021. Click here for more information!


Notice:  EPA’s Health and Environmental Risk Assessment (HERA) National Research Program is announcing for public comment and external peer review the release of the draft Supplement to the 2019 Integrated Science Assessment for Particulate Matter (PM). The HERA research program has been designed to develop and apply state-of-the-science research to characterize impacts on human and ecological systems – whether they result from exposure to single, complex, or multiple physical, chemical, or biological stressors – to support and improve EPA’s risk assessment and risk management decisions. Integrated Science Assessments (ISAs) fall under HERA’s Science Assessment Development Research Area which is focused on producing high quality, transparent, consistent, and scientifically-defensible assessment products to meet EPA’s diverse statutory and policy needs.

This draft Supplement represents a targeted evaluation of recent studies published since the literature cutoff date for the 2019 PM ISA. The 2019 PM ISA and this Supplement form the complete scientific record for the ongoing reconsideration of the primary (health-based) and secondary (welfare-based) National Ambient Air Quality Standards (NAAQS) for PM. The 2019 PM ISA and Supplement, in conjunction with additional technical and policy assessments, will inform EPA’s decisions on the reconsideration of the current NAAQS and the appropriateness of possible alternative standards.

The draft assessment is available for a 60-day public comment period, which ends on November 29, 2021. Written comments should be submitted to EPA-HQ-ORD-2014-0859 via Comments submitted to EPA, via the public docket, will be provided to the external peer review panel. The date and location of a public meeting for the external peer review panel will be specified in a separate Federal Register notice.

For more information on the PM ISA Supplement, including how to submit comments, please visit the Federal Register or the EPA ISA website. For more information on HERA, please see the program’s Strategic Research Action Plan.

Updates on EPA Efforts to Address PFAS in Pesticide Packaging

This original announcement was published by the EPA on September 30, 2021. Click here for more information.


The U.S. Environmental Protection Agency (EPA) continues to work diligently to address per-and polyfluoroalkyl substances (PFAS) in the environment and is providing important updates on its progress in testing pesticide products and containers for PFAS.

Today, with the purpose of advancing sound science and providing transparency in its research, EPA is releasing an internally validated method for the detection of 28 PFAS compounds in oily matrices, such as pesticide products formulated in oil, petroleum distillates, or mineral oils. The oily matrix method is modified from EPA Method 537.1, a method that is mainly used for drinking water and was previously used in analyzing PFAS in fluorinated high-density polyethylene (HDPE) containers.

The new method is intended to help pesticide manufacturers, state regulators, and other interested stakeholders test oily matrix products for PFAS and join the effort in uncovering any possible contamination. In a shared interest to remove PFAS from the environment, if companies find PFAS in their product, EPA is requesting that they engage in good product stewardship and notify the Agency.

Through close collaboration with the Maryland Department of Agriculture, EPA used this oily matrix method to analyze three stored samples of mosquito control pesticide products (Permanone 30-30 and PermaSease 30-30) and obtained samples directly from the product line from the pesticide manufacturer. After thoroughly analyzing the samples and conducting an in-depth quality assurance and quality control process, the Agency determined that none of the tested samples contained PFAS at or above the Agency’s method limit of detection. To date, the only PFAS contamination in mosquito control pesticide products that the Agency has identified originated from fluorinated HDPE containers used to store and transport a different mosquito control pesticide product (Anvil 10-10).

While it continues its investigation, the Agency will use all available regulatory and non-regulatory tools to determine the scope of this emerging issue and its potential impact on human health and the environment. EPA continues to test additional fluorinated containers to determine whether they contain and/or leach PFAS and will be presenting those results when the studies are complete. The Agency is working with other federal agencies and trade organizations to raise awareness of this emerging issue and discuss expectations of product stewardship. EPA also is encouraging the pesticide industry to explore alternative packaging options, like steel drums or non-fluorinated HDPE.

As more information becomes available, EPA will continue to work in collaboration with other federal entities to provide guidance to states and localities that may be affected by PFAS in pesticide containers.

To access the oily matrix method report and to learn more, please visit: 

Aquatic Life Benchmarks for Registered Pesticides

This original announcement was published by the EPA on August 31, 2021. Click here for more information.


The U.S. Environmental Protection Agency (EPA), in collaboration with the California Department of Pesticide Regulation and the U.S. Geological Survey, has released an updated version of the Aquatic Life Benchmarks. Aquatic Life Benchmarks are estimates of the concentrations below which pesticides are not expected to present a risk of concern for freshwater organisms.

The updated Aquatic Life Benchmarks represent newly registered pesticides or new values for previously registered pesticides and selected degradates. This is the first update to include benchmarks for 18 additional antimicrobial chemicals. While antimicrobial chemicals have been included as benchmarks in the past when they have dual uses as conventional pesticides, recently there has been an increased interest in a broader array of antimicrobial compounds due to their use against COVID-19.

EPA based these benchmarks on toxicity values from scientific studies that the agency has reviewed and has used in publicly accessible ecological risk assessments in support of regulatory decisions for pesticides. For each of the chemicals listed, the table provides a link to the source documents from which each of the benchmarks is extracted.

Comparing a measured concentration of a pesticide in water to Aquatic Life Benchmarks can be helpful in interpreting monitoring data and in identifying and prioritizing monitoring sites that may require further investigation. State, tribal, and local governments use these benchmarks in their interpretation of water monitoring data. International regulatory authorities and researchers also use these data in their work.

EPA’s goal is to add to these benchmarks on an annual basis; the last update was published September 28, 2020.

EPA Releases Draft Biological Evaluations of Three Neonicotinoids for Public Comment

This original announcement was published by the EPA on August 26, 2021. Click here for more information.


EPA is releasing its draft biological evaluations (BEs) for clothianidin, imidacloprid and thiamethoxam, which are part of a group of insecticides known as the neonicotinoids, for public review and comment. These neonicotinoids are used on a variety of crops, turf, and ornamentals, among other residential and commercial indoor and outdoor uses.

EPA evaluated clothianidin, imidacloprid and thiamethoxam to determine whether they may affect one or more species listed under the Endangered Species Act (ESA) or their designated critical habitats. The draft BEs find that each of these chemicals is likely to adversely affect certain listed species or their designated critical habitats.

The “likely to adversely affect” (LAA) determination means that EPA reasonably expects that at least one individual animal or plant, among a variety of listed species, may be exposed to the pesticide at a sufficient level to have an effect, which will be adverse. The LAA threshold for a BE is very sensitive because the likely “take” of even one individual of a species, which includes unintentional harm or death, triggers an LAA determination. This is the case even if a species is almost recovered to a point where it no longer needs to be listed. As a result, there are often a high number of “may effect” and LAA determinations in a BE. An LAA determination, however, does not necessarily mean that a pesticide is putting a species in jeopardy. Jeopardy determinations are made by the U.S. Fish and Wildlife Service and the National Marine Fisheries Service (collectively “the Services”) in the course of a formal consultation that evaluates any effects of the pesticides on entire species.

A BE is a document that contains EPA’s analysis of the effects of a pesticide on federally threatened or endangered species and their designated critical habitat, and any conclusions that the pesticide may affect, and is likely to adversely affect, any of these species or habitats. The BE is used to initiate consultation with the Services, if needed. This evaluation encompasses all registered uses and approved product labels for pesticide products containing these chemicals.

When formal consultation is necessary, the Services use the information in EPA’s final BE to develop their biological opinions (BiOps). In their BiOp, the Services document their determination of whether a pesticide jeopardizes the continued existence of the species and whether there will be adverse modification to its designated critical habitat. If jeopardy or adverse modification is determined, the Services, with input from EPA, will propose additional protections.

The draft BEs released today were developed after the release of EPA’s proposed interim decisions (PIDs) for the neonicotinoid pesticides in January 2020. As part of the PIDs, EPA has begun the process of proposing mitigation measures, such as annual application rate reductions and application timing restrictions under the Federal Insecticide, Fungicide, and Rodenticide Act, which will be finalized after the completion of the final BEs. Additional mitigation measures may be developed through formal consultation on the neonicotinoid pesticides. EPA is interested in finding ways, through discussions with stakeholders, to implement mitigation measures that further protect endangered and threatened species earlier in the ESA consultation process.

Read the draft biological evaluations for clothianidinimidacloprid and thiamethoxam on our webpage. To learn more about these BEs, see the Frequently Asked Questions. EPA is accepting public comments for 60 days upon publication via docket EPA-HQ-OPP-2021-0575 at, and will finalize the BEs after reviewing the comments.

EPA Announces Plan for Pet Incident Reporting and Releases Proposed Interim Decisions for Four Pesticides

This original announcement was published by the EPA on August 3, 2021. Click here for more information.


The U.S Environmental Protection Agency (EPA) is announcing its plan collect pet incident data on four pesticides used in a variety of agricultural and non-agricultural settings, including in residential pet products. These pesticides are MGK-264, piperonyl butoxide (PBO), pyrethrins, and amitraz.

In its overall efforts to protect pets under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), EPA intends to request enhanced incident reporting and sales data for these pet products to align with what is already submitted for spot-on products. These data would allow the agency to conduct a comparative assessment of pet incidents across registered pet products based on sales data to better determine whether any changes to the pet product registrations and labels are necessary. EPA is interested in feedback from stakeholders on the most efficient way these data can be provided to the agency and types of analyses that could be submitted to expedite the agency’s assessment. EPA is also considering additional measures that could enhance its oversight of pet products, such as additional targeted studies and monitoring, and welcomes public comments on these and other potential measures.

Additionally, EPA is releasing proposed interim decisions (PIDs) for MGK-264, PBO, and pyrethrins to address potential human health and ecological risks. EPA is also releasing the PID for amitraz. FIFRA requires the agency to periodically re-evaluate pesticides through registration review to ensure that risk assessments and pesticide decisions reflect the best available science. Registration review is a multi-step process to identify risks as well as actions that can mitigate risks.

Based on the findings in the draft human health and ecological risk assessments and feedback submitted during the public comment periods, EPA is proposing the following mitigation measures for MGK-264, PBO, and pyrethrins:

  • Additional personal protection equipment for several occupational handler scenarios;
  • Prohibiting certain applications via indoor dusters, shakers, aerosol space sprays, handheld/portable misters and foggers, and liquid spray applications;
  • Adding mandatory spray drift management label language (PBO and pyrethrins only); and
  • Cancelling multiple products/uses for certain residential, commercial (e.g. food handling establishments, warehouses) and indoor agricultural use (e.g., poultry houses, animal quarters).

For amitraz, the agency did not identify any human health risks of concern. Additionally, the agency has concluded that, although the potential ecological risks are limited only to honey bees in hives treated with amitraz, the risks are low and has, therefore, made a “no effect” determination for species groups for amitraz products under the Endangered Species Act. EPA is not proposing any risk mitigation for amitraz.

Upon publication of Federal Register notice, public comments will be accepted for 60 days in the registration review dockets, EPA-HQ-OPP-2012-0415 (MGK-264), EPA-HQ-OPP-2010-0498 (PBO), EPA-HQ-OPP-2011-0885 (pyrethrins) and EPA-HQ-OPP-2009-1015 (amitraz) at

After a thorough review of the science and carefully considering scientific peer review and public comments, EPA will proceed with the registration review process for MGK-264, PBO, pyrethrins, and amitraz. The next step in the FIFRA registration review process is the interim decision, which imposes risk mitigation measures necessary to protect human health and the environment.

Background on Pesticide Uses

Pyrethrins are a mix of six compounds used as insecticides to target a wide range of pests in agricultural and non-agricultural settings. Pyrethrins are also registered for use in residential pet products, such as pet shampoos, pet spot-ons, and pet dusts.

MGK-264 and PBO are insecticide synergists used in combination with a variety of insecticides such as the pyrethrins and pyrethroids. Synergists are chemicals that, while lacking pesticidal properties of their own, enhance the pesticidal properties of other active ingredients. The use patterns for PBO are similar to the pyrethrins. MGK-264 has similar indoor commercial and indoor residential uses, but has no agricultural crop uses. Outdoor uses of MGK-264 are limited to building surface treatments. Both MGK-264 and PBO are registered for use in residential pet products, such as pet shampoos, pet spot-ons, and pet dusts.

Amitraz is an insecticide/acaricide currently registered for use in pet collars for control of ticks on dogs and in impregnated strips for control of Varroa mites in beehives.

EPA Finalizes New, Stronger Safety Measures for Pesticide Paraquat

This original announcement was published by the EPA on August 2, 2021. Click here for more information.


The U.S. Environmental Protection Agency (EPA) is releasing the interim decision (ID) for the pesticide paraquat dichloride (paraquat) finalizing new, stronger safety measures to reduce exposure. The Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) requires the agency to periodically re-evaluate pesticides through registration review to ensure that risk assessments and pesticide decisions reflect the best available science. The ID is part of the legally required registration review process to identify risks as well as actions that can mitigate risks.

Paraquat is an herbicide applied annually to control invasive weeds and grasses in crops including cotton, corn, and soybeans. No direct one-to-one alternatives to paraquat are available. All paraquat products are Restricted Use Products and may only be used by certified pesticide applicators.

The agency has taken proactive steps to ensure paraquat is used in a manner that will not cause unreasonable adverse effects to human health or the environment and is consistent with the label directions. EPA’s 2016 Paraquat Human Health Mitigation Decision included a safety awareness campaign, targeted training for paraquat applicators, and changes to labels and product packaging to help prevent illness, injury, or death resulting from improper use.

The ID released today builds upon this previous work and includes the following enforceable mitigation measures that specify parameters for application and institute restrictions to further protect individuals from exposure. EPA has determined that these mitigation measures are necessary to address the risks identified from paraquat exposure while allowing for the continued use of this important agricultural tool.

  • Limiting aerial applications and requiring residential buffers.
  • Prohibiting pressurized handgun and backpack sprayer applications.
  • Requiring enclosed cabs or respirators for groundboom applications.
  • Increasing the Restricted Entry Interval (REI) for several crops.

Additionally, EPA evaluated hundreds of studies, including published toxicity and epidemiology literature on paraquat exposure and adverse health outcomes, including Parkinson’s Disease. There are many studies on paraquat and Parkinson’s Disease that range in quality and provide conflicting results. Following EPA’s 2019 literature review, an updated study of the Agricultural Health Study cohort was published in 2020 that reported no association between paraquat exposure and Parkinson’s Disease. Notably, this updated study did not replicate earlier 2011 findings from AHS that were considered by EPA and suggested a potential association may exist. After a thorough review of the best available science, as required under FIFRA, EPA has not found a clear link between paraquat exposure from labeled uses and adverse health outcomes such as Parkinson’s disease and cancer.

The new safety measures announced today will significantly reduce potential human health risks and are protective of all potential human health outcomes, including Parkinson’s disease.

More information about paraquat and the interim decision is available on EPA’s website.

EPA Proposes Registration of New Nematicide Active Ingredient

This original announcement was published on July 23, 2021. Click here for more information.


The U.S. Environmental Protection Agency (EPA) is taking comments on its proposal to register the new pesticide active ingredient fluazaindolizine for agricultural use.

Fluazaindolizine is a sulfonamide nematicide that EPA expects will play a role in resistance management and integrated pest management programs to help delay the further development of nematicide resistance.

Proposed uses of fluazaindolizine include carrots and cucurbit vegetables and certain fruiting, tuberous, and corm vegetables. Other use sites include certain other crops that will not bear fruit within a year of nematicide application: citrus fruit, stone fruit, tree nuts, and small vine-climbing fruit (except fuzzy kiwi).

The human health and ecological hazard profiles for fluazaindolizine indicate that it is a reduced-risk alternative for all its proposed uses when compared to registered alternatives.

After conducting robust scientific assessments, EPA concluded that there are no risk concerns for humans. The ecological risk assessment showed no risk concerns for non-listed (i.e., not endangered or threatened) fish, aquatic invertebrates, plants, and birds. Risks have been identified for mammals and honey bees near use sites. These risks are mitigated with label instructions requiring soil incorporation and mandatory spray drift restrictions for broadcast applications.

EPA is committed to making progress on protecting endangered species, including conducting analyses and putting mitigations in place earlier in the registration process. For listed (i.e., endangered or threatened) species, EPA has made no-effect determinations for fish, aquatic invertebrates, and aquatic plants that do not rely on terrestrial organisms for habitat, prey, or pollination services.

Although EPA has not made effects determinations for listed birds (including reptiles and amphibians), mammals, terrestrial invertebrates, and terrestrial plants, or aquatic listed species that rely on terrestrial organisms, the agency has added mitigation to reduce potential exposure to terrestrial species. EPA expects that this mitigation may also reduce potential risks to groups that rely on terrestrial organisms for habitat, prey, or pollination services. Proposed mitigation includes mandatory spray drift language, prohibition of overhead chemigation, application of fluazaindolizine to the ground under the plant canopy, and mandatory incorporation into the soil by mechanical means or water.

EPA is accepting public comments on this proposal through docket EPA-HQ-OPP-2020-0065 at for 15 days.

EPA Offers Virtual Training for Pesticide Applicators in Indian Country

This original message was published by the EPA on July 16, 2021. Click here for more information. 


The Environmental Protection Agency (EPA) is offering a free, two-day training webinar on August 11-12, 2021, to certify participants as private applicators of restricted-use pesticides (RUPs) in Indian country under the EPA Plan for the Federal Certification of Applicators of Restricted Use Pesticides within Indian Country (EPA Plan). 

RUPs require special care to avoid harming human health and the environment. In accordance with the requirements in 40 CFR § 171, RUPs can only be sold to or used by pesticide applicators who are specially certified, or to persons under the direct supervision of a certified applicator. RUPs can only be used in areas where EPA has explicitly approved or implemented an applicator certification plan for that state, tribe or federal agency.

Any person who uses RUPs within Indian country under the EPA Plan needs a federal certification from EPA. Additionally, some tribes may choose to further restrict or prohibit the use of RUPs in their areas through the implementation of tribal codes, laws, regulations or other applicable requirements. The EPA Plan does not supersede such tribal requirements. Applicators of RUPs in Indian country should take steps to determine if there are additional tribal requirements they must follow.

Applicators interested in attending the two-day, 12-hour course should express interest by emailing by August 9, 2021. EPA plans to hold another training on November 17-18, 2021.

Comment Period Extended for Draft Risk Assessments and Proposed Mitigation Measures for Sulfuryl Fluoride

This original announcement was published by the EPA on July 15, 2021. Click here for more information.


EPA has extended the public comment period for the draft risk assessments and proposed mitigation measures for sulfuryl flouride. Comments are now due by September 23, 2021 and should be submitted to docket EPA-HQ-OPP-2009-0136 at

For the registration review of sulfuryl fluoride, which includes all the uses of the pesticide, EPA released sulfuryl fluoride draft risk assessments (DRAs), including the combined ecological draft risk assessment and drinking water assessment, and the occupational and residential risk assessment for public comment in May 2021.

The DRAs are part of a multi-step process to identify risks as well as actions that can mitigate risks. After considering public comments, EPA will proceed with registration review by issuing the proposed interim decision, which will propose measures to reduce human health and ecological risks.

The Sulfuryl Fluoride Draft Interim Re-entry Mitigation Measures Memorandum also released in May 2021 outlines the new safety measures EPA is proposing for fumigation uses and is in response to the EPA Office of Inspector General’s December 2016 Report No. 17-P-0053 that was conducted to assess which additional safety measures could be taken to prevent serious injuries from use of this pesticide during residential fumigation.

After a thorough review of public comments, EPA will issue the Final Interim Re-entry Mitigation Measures Memorandum, including the label requirements for sulfuryl fluoride products.

Additional information on sulfuryl fluoride can be found on EPA’s website.