Sulfoxaflor

In 2019, EPA registered new uses for the insecticide sulfoxaflor and restored previously registered uses. This decision is backed by substantial data and ensures that, when used according to the label, sulfoxaflor poses no significant risk to human health and lower risk to non-target wildlife, including pollinators, than registered alternatives. Sulfoxaflor is an effective tool for growers that has a lower environmental impact because it disappears from the environment faster than widely used alternatives like neonicotinoids. Growers may have seen substantial losses (up to 50 percent for certain crops) due to pests that can now be treated with sulfoxaflor.

Read the registration decision for sulfoxaflor.

Learn more about sulfoxaflor:

Basic information on uses
2019 registration decision
Human and ecological health
Endangered Species Act assessments
Pollinator protection
EPA actions and regulatory history

Basic Information on Uses

Sulfoxaflor is a sulfoximine, a newer insecticide class that was first registered by EPA in 2013. It is effective against pests that are becoming resistant to carbamate, neonicotinoid, organophosphate and pyrethroid insecticides.

Sulfoxaflor is an important and highly effective tool for growers that targets difficult pests such as aphids and tarnished plant bugs (lygus). These pests can cause significant economic loss, leading several states to request emergency exemptions in recent years. There are few viable alternatives for sulfoxaflor. In many cases, alternative insecticides may be effective only if applied repeatedly, whereas sulfoxaflor typically requires fewer applications resulting in less risk to non-target pests and plants.

2019 Registration Decision

EPA’s 2019 registration decision for sulfoxaflor adds the following new uses: alfalfa, corn, cacao, grains (e.g., millet, oats), pineapple, sorghum, teff, teosinte, and tree plantations. This action also restores citrus, cotton, cucurbits, soybeans and strawberries to the labels.

This decision also removes the following application restrictions originally put in place by the 2016 registration decision. Widely used alternatives do not have these restrictions and may pose higher risk to non-target wildlife than sulfoxaflor.

EPA removed the prohibition of use on crops grown for seed because pollinator protection restrictions, including low use rates, will be in place regardless of whether the crop is grown for seed or for commodity harvest.
EPA removed the restriction to post-bloom application for bee-attractive crops only when there is low risk or limited potential for exposure to bees.
The 12-foot buffer requirement was lifted because EPA believes the spray drift mitigation requirements on labels are adequate to limit drift.
EPA removed the 2016 restriction against tank mixing because data show that there is no additional risk when sulfoxaflor is tank mixed with other compounds.

Human and Ecological Health

Under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), EPA must determine that the use will not cause unreasonable adverse effects on human health or the environment.

After reviewing the data, EPA has determined that, when used according to the label requirements, sulfoxaflor does not pose a risk of concern for people, including infants, children and agricultural workers and that, overall, sulfoxaflor presents a low risk to birds, mammals, fish, and other aquatic animals and plants. To reduce the risk to pollinators, the label will include instructions for pollinator protection and crop-specific restrictions. See the following section for more information on measures to protect pollinators.

Endangered Species Act Assessments

The U.S. Environmental Protection Agency (EPA) has released its final biological evaluation (BE) and its response to comments received on the draft BE. Sulfoxaflor is an insecticide used on a variety of crops to target difficult pests such as aphids and tarnished plant bugs (lygus). As an alternative to older insecticides including carbamates, neonicotinoids, organophosphates, and pyrethroids—sulfoxaflor typically requires fewer applications resulting in less exposure to non-target pests and plants.

In the BE, EPA evaluated sulfoxaflor to determine the potential effects on federally listed endangered and threatened (listed) species and their designated critical habitats, along with predictions of whether sulfoxaflor is likely to jeopardize endangered and threatened (listed) species or adversely modify designated critical habitats. The BE is part of EPA’s efforts to meet its obligations under the Endangered Species Act (ESA). This work furthers the goals outlined in EPA’s April 2022 ESA Workplan to provide practical protections from pesticides for listed species.

EPA carefully considered the comments on the draft biological evaluation received during the public comment period in 2022. Additionally, since the draft BE was issued, the registrant provided comments and submitted revised proposed labels that EPA incorporated in the analysis for the final BE. The revised proposed labels, once approved, would decrease exposure (e.g., reducing aerial application rates for certain use patterns, prohibiting aerial application for certain uses) which resulted in a reduction of the “likely to adversely affect” determinations and jeopardy/adverse modification predictions in the final BE.

In the final BE, and taking into account the new mitigations in the revised proposed labels, EPA evaluated the effects of sulfoxaflor on more than 1,700 listed species and more than 800 designated critical habitats in the United States, determining that sulfoxaflor:

Will cause no effect to 47 percent of listed species and 54 percent of critical habitats (as compared to 36 percent and 52 percent, respectively from the draft BE, which did not include the mitigations in the revised proposed labels);
May affect but is not likely to adversely affect 22 percent of listed species and 37 percent of critical habitats (as compared to 30 percent and 35 percent, respectively, from the draft BE, which did not include the mitigations in the revised proposed labels);
Is likely to adversely affect but EPA predicts the likelihood that use will not cause jeopardy to 27 percent of listed species or adversely modify 6 percent of critical habitats (as compared to 27 percent and 9 percent, respectively from the draft BE which did not include the mitigations in the revised proposed labels); and
Is likely to adversely affect and EPA predicts the likelihood that use may cause jeopardy to 4 percent of listed species and adversely modify 3 percent of critical habitats (as compared to 7 percent and 4 percent, respectively from the draft BE which did not include the mitigations in the revised proposed labels).

Since EPA determined that sulfoxaflor is likely to adversely affect certain listed species and/or critical habitats, the Agency has initiated formal consultation with the U.S. Fish and Wildlife Service and National Marine Fisheries Service (collectively “the Services”). EPA will also continue discussions with the registrant to determine what additional mitigation measures could be implemented to further protect listed species and critical habitats while the consultation is ongoing.

During formal consultation, the Services use EPA’s effects determinations to inform their biological opinions, which will include their final determinations of whether a pesticide jeopardizes each relevant listed species and/or adversely modifies designated critical habitats. The Agency intends to work with the sulfoxaflor registrant, as well as the Services and other stakeholders, during the formal consultation process to identify additional mitigation measures to protect listed species and/or designated critical habitats.

The final BE and the response to comments are available in docket EPA-HQ-OPP-2010-0889 on regulations.gov

Pollinator Protection

To ensure that sulfoxaflor can be used by growers while still maintaining protection for pollinators, EPA reviewed additional studies provided to the Agency on sulfoxaflor’s effect on bee colonies and over a dozen studies on the potential for bees to be exposed post-application.

To minimize potential exposure to bees near treated areas, the following statements/requirements are required on end-use product labels:

Environmental Hazards Statement:
“This product is highly toxic to bees and other pollinating insects exposed to direct treatment or to residues in/on blooming crops or weeds. Protect pollinating insects by following label directions intended to minimize drift and reduce pesticide risk to these organisms.”

The RT₂₅ (how long foliar residues of sulfoxaflor exhibit toxicity to honey bees):
“The RT₂₅ for this product is less than or equal to 3 hours.”

Directions for Use:
“Notifying known beekeepers within 1 mile of the treatment area 48 hours before the product is applied will allow them to take additional steps to protect their bees. Also, limiting application to times when managed bees and native pollinators are least active, e.g., 2 hours prior to sunset or when the temperature is below 50°F at the site of application will minimize risk to bees.”

To further protect pollinators from potential exposure, EPA requires the following crop specific restrictions:

Citrus: Only one application is allowed between 3 days before bloom and until after petal fall per year.
Ornamentals: Do not make more than one application during bloom. The single application during bloom must not exceed a rate of 0.071 lb ai/acre.
Pome Fruit, Stone Fruit, Tree Nuts and Pistachio: Do not apply this product any time between 3 days prior to bloom and until after petal fall.
Small Fruit Vine Climbing & Low Growing Berry, Tree Plantations: Do not apply this product any time between 3 days prior to bloom and until after petal fall.

EPA Actions and Regulatory History

In May 2013, EPA registered sulfoxaflor; however, that registration was canceled by the Ninth Circuit Court of Appeals after the court decided that the registration did not have enough data on the effects on bees.

After the court's decision, EPA issued a cancellation order to address the use of existing stocks. Although the product registrations were vacated, the tolerances for sulfoxaflor residues on treated commodities that were established under the Federal Food, Drug and Cosmetic Act remain in place.

In 2016, EPA reevaluated the data and approved registrations for crops that do not attract bees and for crops where sulfoxaflor would be applied when bees would not be present. These changes reduced the risk to bees below EPA's level of concern such that no additional data requirements were triggered.

In support of the current registration, the registrant submitted additional data on the potential for long-term effects on bees with which EPA conducted a new comprehensive risk assessment. Based on this assessment, EPA restored the remainder of the previously approved uses, added new uses and removed some of the application restrictions from the 2016 registration.