Document ID: EPA-HQ-OPP-2008-0331-0180
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2021-01-04T05:00Z

Participants: Participants
Appleyard, Moana (Meeting Organizer)
Paul Hendley (Accepted in Outlook)
David W Haughey (Accepted in Outlook)
Britton, Cathryn
Biscoe, Melanie (Accepted in Outlook)
Nguyen, Khue (Accepted in Outlook)
Costello, Kevin
Sappington, Keith (Accepted in Outlook)
Sankula, Sujatha (Accepted in Outlook)
Orrick, Greg
Housenger, Justin
Garber, Kristina (Tentative in Outlook)
Steeger, Thomas
Summers, Holly
Stebbins, Katherine
Kiernan, Brian
Jill Holihan (Accepted in Outlook)
Charles Levey (Declined in Outlook)
Thomas, Samantha (Accepted in Outlook)
Tim Formella (Accepted in Outlook)
Schlekau, Julie
Steve Ditto
Anderson, Brian
Jan Brill
Mroz, Ryan
Jennifer Collins

Background: Members of EPA's pyrethroids team from the Environmental Fate and Effects Division (EFED) and the Pesticide Re-evaluation Division (PRD) met with representatives from the Pyrethroid Working Group (PWG) to discuss their proposal to bridge the honeybee data, required in the pyrethroids Interim Decisions (IDs). The Data Call-Ins (DCIs) will be issued for pyrethroids with foliar agricultural uses in 2021. 

The PWG presented their proposal to bridge the pollinator data (attachment).

Agency concerns/comments on the PWG proposal:

 Tier 1 Data.  The Agency is concerned that the PWG proposal appears to assume sufficient Tier 1 data on the pyrethroids is available and that additional tier 1 data would not be necessary because results the 2016 Tier 1 risk assessment indicate acute risk concerns for all 9 pyrethroids/pyrethrins assessed.  This approach is problematic and inconsistent with the Agency risk assessment method established for other taxa where acute and chronic risk are assessed regardless of the outcome of acute risk assessment.  Currently, the Agency does not know the extent of chronic risk to bees and we have data which indicate certain pyrethroids are found in relevant hive matrices.  Chronic effects to larvae are expected based on information for some pesticides.  In addition, these data are needed to better understand effects that may occur within a hive, and possibly inform higher tier (colony-level study designs) and/or colony simulation models.  EPA would likely use the acute to chronic ratio method, and determine if there are patterns in the data.  In the 2016 assessment, acute RQs vary by a factor of 100 across multiple compounds--for chronic data, EPA would expect to see similar variance.  The chronic tier I data would also help inform ESA assessments and risk to non-apis bees. 
 PWG chemicals vs the other Pyrethroids.  The Agency is concerned that the PWG proposal appears to only pertain to the PWG pyrethroids. It is likely that other non-PWG pyrethroids would also have bee exposure concerns. The Agency will work with non-PWG companies to discuss potential bridging and solicit data that might be useful in an over-arching bridging strategy, because EPA believes a bridging proposal should ultimately encompass all registered pyrethroids where significant exposure of bees is expected.
 Off-Field Risk. It appears that the PWG equates "no applications during bloom" as "no bee exposure." Furthermore, the label language being cited by the PWG (e.g., "do not apply to blooming crops when bees are visiting.") is taken from the environmental hazards section of the label, and is interpreted as advisory by state lead agencies because of its location on the label. For foliar applications, off-field exposure from spray drift is expected.  The Agency believes that Tier 1 data may be needed to evaluate off-field risk, particularly in situations where risks are high and present a large spatial footprint (e.g., for major bee-attractive crops like soybean). 
 RT25.  The PWG proposal identifies the RT25 study as a `key part' of the pyrethroid pollinator data call in.  The Agency is concerned with this approach, given the uncertainty associated with generating RT25 values and their limitations for use in risk assessment. One issue with this data is the process proposed by the PWG is heavily reliant on a viable protocol for developing an RT25.  The Agency has not yet refined the existing protocol for this data and more refined methods may be needed to fully address the greatest contributor to variability, i.e., environmental weathering.  Also, based on available data, the RT25 appears to be dependent on formulation which would mean that for each active ingredient of particular concern, tests would have to be available on specific formulated end-use products.  Since the RT25 protocol is still in development, it could be a number of years before a robust protocol can be validated.  EPA is concerned about the timeframe.  EPA encouraged the PWG to think about developing tier 1 studies first, then based on results of tier 1 testing can further discuss with EPA the need for tier 2/3 testing and RT25 testing.  
 Higher Tier Residue Data. Given the tier 1 risks already identified, the incident reports and potential for on field exposure from applications made at bloom, pollen and nectar residue data will likely be needed for some pyrethroid uses. The PWG proposal does not provide details on what crops and pyrethroid active ingredients may be tested and how data may be bridged among chemicals.