Pyrethroid Pollinator Risk Assessment Proposal Overview

The Pyrethroid Working Group conducted a comprehensive investigation into existing pyrethroid study data to address EPA's request for a pollinator risk assessment. The proposal aims to bridge pollinator datasets across pyrethroids efficiently, avoiding duplicate data submissions. Key factors impacting pollinator risk were identified, and summaries of available pollinator studies were shared anonymously. The process suggestions outlined focus on ensuring robust decision-making and predictability while understanding uncertainties in bridging data.

• Pyrethroid
• Pollinator Risk Assessment
• EPA Request
• Proposal Overview

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1. Proposal for Pyrethroid Pollinator Risk Assessment in Response to EPA Request. Pyrethroid Working Group 0930 October 28th, 2020. Online discussion 10/28/2020 PWG Pollinator Assessment Process Suggestions 1

2. Agenda for Telecon Introductions Background Outline of proposal Discussion 10/28/2020 PWG Pollinator Assessment Process Suggestions 2

3. Background Pyrethroids are very effective insecticides and consequently many uses typically fail Tier 1 in the pollinator risk assessment scheme see EPA Sept 30, 2016 Tier 1 review. For good and well-argued reasons, EPA regulated most pyrethroids as a class for aquatic ecological risk. This reflected the fact that pyrethroid AIs share the same MoA and, although having different intrinsic activities against pests, are applied at differential rates that ensure equivalent pest control for all AIs. Moreover, their environmental fate behavior is largely similar across AIs. Because pyrethroids behave very similarly within their class, EPA has requested proposals from registrants which might support bridging pollinator datasets across pyrethroids and avoid duplicative data submissions to avoid requiring unnecessary data in order to most efficiently use available resources. EPA have also requested that proposals are able to ensure robust decision making by ensuring associated predictability and uncertainty for any bridging is understood. 10/28/2020 PWG Pollinator Assessment Process Suggestions 3

4. There are at least six key factors that may impact risk to pollinators. * Bee matrix is a term encompassing nectar, flowers, pollen, bee bread, royal jelly Formulation impact on AI residue persistence and bee matrix* distribution AI relative pollinator potency AI Environmental Fate Characteristics Bee behavior timing and target Product usage rate applied and timing. Target Crop 10/28/2020 PWG Pollinator Assessment Process Suggestions 4

5. PWG has investigated existing pyrethroid study data PWG companies have examined these factors and shared available pollinator studies anonymously via a contractor to produce summaries. Studies examined: Tier 1 see Figure 56 studies covering many combination of AI and study type. 25 12 Number of studies per test Number Ais with Data No. studies No. AIs 10 20 8 15 6 RT25 studies (7 studies, 6 AIs) covering a wide range of older protocols 1977 2019. type 10 4 5 2 0 0 Adult Acute Contact Adult Acute Oral 5-Pack Test type (total of 56 studies) Acute Larval Adult Chronic Larval Chronic Semi-field and field studies (67 studies on 6 AIs) All but one from EU Conducted at EU application rates which are generally lower than US rates 1980 s to 2018 extremely wide range of study objectives, designs and measured endpoints The majority of these studies have not been submitted to EPA. PWG has examined US pyrethroid product labels and these anonymous summaries for general principles Note that, for confidentiality and anti-trust reasons, these data summaries cannot share individual AI identities. 10/28/2020 PWG Pollinator Assessment Process Suggestions 5

6. Pyrethroids have similar pollinator effective toxicities It is not meaningful to compare pyrethroid pollinator toxicity directly since these AIs have differing intrinsic toxicities to both pollinators and target pests However, field application rates for different AIs also reflect those different activities. Consequently, PWG constructed a table of maximum use rates on three pollinator relevant field crops cotton, almond and peppers. These were then normalized to express a relative potency to one AI. The resulting effective toxicity column provides factors that are applied as follows Estimated rates (kg/ha) Code Name Relative toxicity Cotton 0.112 0.112 0.022 0.045 0.056 0.056 0.224* 0.034 0.028 0.056 0.028 0.336 Almond 0.112* 0.112* 0.022 0.045 0.056 0.112 0.448* 0.037 0.028 0.049 0.025 0.448 Pepper 0.112 0.112* 0.017 0.034 0.056 0.056 0.224* 0.031 0.028 0.049 0.025 0.224 Compound 1A Compound 2A Compound 3A Compound 4A Compound 5A Compound 6A Compound 7A Compound 8A Compound 9A Compound 10A Compound 11A Compound 12A 7.826 7.826 1.400 2.842 3.913 5.101 20.404 2.357 1.957 3.572 1.811 22.779 0.XXX* indicates an inferred or adapted value ???????? ???????? ???????? ???????? ?????? ???????? ?????????? ???????? = The resulting adjusted pollinator endpoints ARE directly comparable 10/28/2020 PWG Pollinator Assessment Process Suggestions 6

7. Pyrethroid AI Pollinator Tier 1 (5-pack) toxicity comparison Adult acute contact ( g a.i./bee) Adult acute oral ( g a.i./bee) Larval Acute ( g a.i./larva) Adult Chronic ( g a.i./bee/day) Larval Chronic ( g a.i./larva) AI Tech. 0.0025 0.0017, 0.0029 Form. Outlier Tech. 0.0089 0.0332, 0.0220 Form. Outlier Tech. 0.0192 Form. Outlier Tech. 0.0358 Form. Outlier Tech. 0.0043 Form. Outlier 1 2 0.0112 0.0132 0.0160 0.0035, 0.0084, 0.0031 0.0049, 0.0345 0.8993 (form) 3 0.0036 0.0008 0.1175, 0.1700 0.0123, 0.0690 0.069 0.1157 4 0.0134 0.0605 0.0109 0.0195 0.0094 0.2931 5 6 0.0038 0.0088 0.0012, 0.0078, 0.0025 0.0153 0.1431 0.0166 0.0043 0.0051 0.0038 0.0080, 0.0093 7 0.0078 0.0554 8 9 0.0467 0.0806 0.1257 0.0153 0.0036, 0.0104 0.0639 0.0033 0.0073, 0.0064 10 0.014 Data show fair agreement between adjusted toxicities Outlier study data reflect lower toxicities than bulk of data. Show little difference between formulation and technical toxicity data. Confirms that these pyrethroids (and, by analogy, others) do not pass screening level RA Indicates that further laboratory studies for PWG AIs will not change pyrethroid pollinator risk assessments and therefore that additional Tier 1 (5-pack) testing on remaining PWG pyrethroid formulations/technical material is not necessary. 10/28/2020 PWG Pollinator Assessment Process Suggestions 7

8. Pyrethroid semi-field/field study findings summary General observations Semi-field/Field studies are inherently variable and protocol/methodological differences make specific comparisons difficult. Bee matrix residues were highest on Day 1 and thereafter showed sharp declines as expected due to the non-systemic behavior of pyrethroids. Only applications associated with blooming periods generated any impacts and those were rate dependent and transient Any effects were at the individual level rather than on the colony. Any effects on individuals, if seen, were clearly transient and reduced with time after application. As expected, effects were reduced in field studies relative to tunnel studies. Effects were reduced considerably when applications were made in the evening after bee flight has ceased. All AIs exhibited some form of repellency (e.g. reduced flight intensity and reduction in foraging) even at relatively low (EU) application rates 10/28/2020 PWG Pollinator Assessment Process Suggestions 8

9. Differentiation based on use pattern Only those use patterns where chemical is applied to bee-attractive crops during bloom are likely to result in exposure Consequently, use patterns that avoid these combinations are not relevant for risk assessment beyond Tier 1 Bloom-associated uses on bee-attractive crops may need to be considered at higher tier 10/28/2020 PWG Pollinator Assessment Process Suggestions 9

10. Where use patterns may be relevant, residual toxicity becomes relevant Pyrethroids share many environmental fate characteristics across the class; however, because of differences in photolytic and catalyzed hydrolytic dissipation rates as well as the design of slow- and fast-release formulations, their persistence on treated crops, pollen, nectar and bee-products can vary more widely. These factors are integrated in the RT25 study designed to measure the rate at which effective pollinator toxicity declines with time. HOWEVER, current RT25 study is acknowledged to be highly variable due (inter alia) to the lack of a standardized protocol or a robust positive control to confirm exposure/assay performance. The Pollinator Research TF (PRTF) are working with EPA to design a reliable and consistent RT25 protocol Because pyrethroid AIs all share the same MoA, are applied at potency-equivalent rates and exhibit highly equivalent pollinator toxicities, PWG believes that, if reliable and comparable RT25data can be obtained for pollinator relevant uses , this can serve as the basis for pollinator risk assessment refinement as a class. For example: If a product* has an RT25 <6 hrs with only late evening applications to blooming crops, then no further higher tier risk assessment is needed If RT25 is >6 hrs then RT25 studies can be used to select REPRESENTATIVE PYRETHROID PRODUCTS as class surrogates for blooming crop use-patterns where field or semi-field studies might be needed e.g. one example each for a medium RT25 and longer RT25 product * Note that since the same AI can have formulations with greatly different RT25 behaviors, we use the term product here to refer to specific formulations or formulation types. 10/28/2020 PWG Pollinator Assessment Process Suggestions 10

11. Reminder: Revised Pyrethroid pollinator label statements for risk mitigation to pollinators This product is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift onto blooming crops or weeds if bees are visiting the treatment area. Protect pollinating insects by following label directions intended to minimize drift and to reduce risk to these organisms. Following best management practices can help reduce risk to terrestrial pollinators. Examples of best management practices include applying pesticides in the evening and at night when pollinators are not foraging and checking to confirm hive locations before spraying. For additional resources on pollinator best management practices, https://www.epa.gov/pollinator-protection/find-best- management-practices-protect-pollinators. Managed pollinator protection plans are developed by states/tribes to promote communication between growers, landowners, farmers, beekeepers, pesticide users, and other pest management professionals to reduce exposure of bees to pesticides. If available, visit state plans for additional information on how to protect pollinators. How to Report Bee Kills -To report bee kills due to pesticide application, please contact the U.S. Environmental Protection Agency at: beekill@epa.gov. 10/28/2020 PWG Pollinator Assessment Process Suggestions 11

12. Summary of PWGs proposal All PWG pyrethroids fail current screening level risk assessments to some degree and their pollinator toxicities are relatively similar when adjusted for their relative field application rates; therefore, additional Tier 1 (5-pack) studies on remaining PWG pyrethroids are not necessary (neither for technical material nor formulations) Only those uses that lead to potential pollinator exposure (i.e. blooming bee-attractive crops) need to be considered for potential higher tier risk assessments RT25 data will be key to a class-based risk assessment process. Therefore a reliable and consistent RT25 protocol for pyrethroids is needed. PWG offer to conduct some representative RT25 studies next bee season using the new protocol to confirm the reproducibility of this potentially critical element of the tiered process will link with PRTF/EPA exercise Assuming OK, then PWG will conduct RT25 studies (to new EPA-approved protocol) on all PWG pyrethroid products with labels for application at bloom to bee-attractive crops For products with RT25 <6 hr, no further higher tier assessments would be needed Note that we agree with the EPA suggested <6 hr RT25 cutoff value. Where RT25 >6 hr, conduct higher tier assessments and, where necessary for use patterns involving applications at bloom, conduct field or semi-field studies using representative PWG products (e.g. select representative long and medium RT25 products) 10/28/2020 PWG Pollinator Assessment Process Suggestions 12

13. This proposal for the pyrethroid class is pragmatic and efficient because: Pyrethroids area very important tool for growers and have been used very extensively across a very wide range of crops for several decades and there have been relatively few pollinator incidents even given historic labeling. Pyrethroids are well known to be non-systemic. This means that blooms, pollen and nectar residues will decline after topical application with no further chemical being delivered via internal plant transport. Pyrethroids have been shown to exhibit repellency to pollinators, cockroaches, mosquitos, ants, termites etc. Field and semi-field studies at EU application rates support these findings suggesting that pyrethroids benefit from repellency as an additional factor tending to minimize potential exposures. Any effects seen in higher tier studies were transient and not at the colony level Applications made in the evening when pollinators are not visiting blooms show reduced effects Along with new 2020/21 pollinator label statements, this proposal makes stewardship sense and does not require EPA to extrapolate from foreign studies at different rates A realistic number of higher studies may be conducted to agreed protocols on use-patterns/products if needed Using products selected to represent the class, the EPA workload is reduced while the risk assessments can be completed using the same pyrethroids-as-a-class approach as for aquatic risk 10/28/2020 PWG Pollinator Assessment Process Suggestions 13

14. Discussion 10/28/2020 PWG Pollinator Assessment Process Suggestions 14