Bee Testing Requirements Going Forward

Transcription

1 Bee Testing Requirements Going Forward Fred Rice Lange Research and Consulting January 20, 2017 Acknowledgements Max Feken and Jay Overmyer Environmental Safety Syngenta Crop Protection

2 EPA Guidance Document Changed data requirements for all pesticides

3 Pollinator Data Requirements Pre-guidance focus on neonicotinoids Tier 2 Exposure Dietary exposure systemic properties Pollen and nectar residue studies Tier 2 Effects - Sublethal Effects Hive feeding studies Post-guidance focus on all pesticides Tier 1 Exposure Based on conservative exposure estimates Possibility of nectar/pollen data to refine exposure Tier 1 Effects New Tier 1 data requirements adult chronic, acute and chronic larval studies Possibility of higher tier data requirements depending on results from Tier 1 studies (e.g., semi-field and/or feeding studies)

4 Future Present EPA Pollinator Protection Plan Neonicotinoid schedule 2016: Initial set of risk assessments for imidacloprid for public comment (crops with submitted pollen/nectar residue data from application-specific use patterns, and additional open literature data) 2017: Preliminary risk assessments for clothianidin, dinotefuran, and thiamethoxam for public comment 2018: Remainder of final ecological risk assessments for imidacloprid, clothianidin, dinotefuran, and thiamethoxam New harmonized risk assessment guidance for pollinators (June 2014) Implementation of Tier 1 data requirements for all active ingredients (5-6 studies). Prioritizing (i.e., Data Call-In notices) for testing those pesticides with the highest likelihood of both exposure and toxicity.

5 Protection Goals

6 Tiered Approach Separate decision trees for foliar, soil, seed treatments and tree trunk applications Exposure to adults and brood considered Tier I Acute and chronic toxicity values Estimated exposure estimates Tier II Semi-field (tunnel) studies Feeding studies Residue studies Tier III Full field studies

7 Data for Informing EPA's Pesticide Risk Assessment Process for Bees

8 Tier I Effects Testing Adult Bee Acute contact (EPA ) LD50 Acute oral (OECD 213) LD50 10-d chronic feeding (Draft OECD) NOEC/NOED Foliar Residue (EPA ) RT25 (needed if contact LD 50 is <11 ug/bee) Photos provided by Smithers Viscient

9 Tier I Effects Testing Day 1 Day 3 Day 7 Day 15 Larval Bee - Acute 7 or 8-day (OECD 237) LD50 - Chronic 22-day (Draft OECD) NOEC/NOED Day 19 Day 22 Photos provided by Smithers Viscient

10 Tier 1 Risk Assessment Requires Tier 1 Effects Data Uses Conservative Estimated Environmental Concentrations (EECs) PPM concentrations for pollen and nectar foliar applications Possible Tier 2 Scenarios Acutely toxic pesticides (e.g., insecticides) already fail Tier 1 Tier 2 data will likely be required Semi-field studies conducted for some AI s in EU may not be relevant to NA or SA Pollen and nectar residue studies for refinement Other pesticides may fail Tier 1 based on results from larval studies Conduct pollen/nectar residue studies? Conduct Tier 2 effects studies (semi-field and/or colony feeding studies)

11 Tier 2 Exposure Refinement Dietary exposure Measure residues in nectar and pollen for foliar applications prior to or during bloom Assume that residues will be less than Tier 1 EEC? But how much lower will they need to be? Residue data from foliar applications during bloom (at t=0) could be compiled and used for all pesticides applied to that crop (not pesticide specific).

12 Tier I Exposure Estimated based on models, literature or conservative values (all equations are part of BeeRex which is available to the public) Foliar applications Dietary T-REX tall grass upper bound value = 110 mg/kg per 1 lb ai/a Contact Koch and Weisser (1997) = 2.7 µg ai/bee per 1 lb ai/a Soil applications Briggs model Seed treatments Default value of 1 mg/kg (EPPO tier I screening value)

13 Tier I Dose Calculations Foliar Applications Dietary Adults: 110 mg ai/kg food X 292 mg food/bee = 32 µg ai/bee Larvae: 110 mg ai/kg food X 120 mg food/bee = 13.2 µg ai/bee Contact Maximum residue level on honey bees = 2.7 µg ai/bee Soil Applications Dietary Adults: Briggs model EEC X 292 mg/food/bee Larvae: Briggs model EEC X 120 mg food/bee Seed Treatment Dietary Adults: 1 mg ai/kg food X 292 mg food/bee = 0.29 µg ai/bee Larvae: 1 mg ai/kg food X 120 mg food/bee = 0.12 µg ai/bee

14 Tier I Risk Quotients (Acute) Foliar applied Dietary Adults: 32 µg ai/bee x App. rate / oral LD50 Larva: 13.2 µg ai/bee x App. rate / LD50 Contact Adults: 2.7 µg ai/bee x App. rate / contact LD50 App. Rate = lbs ai/a Assessment Criteria LOC = 0.4 RQ < 0.4 (Pass) RQ 0.4 (Fail) Soil applied Dietary Adults: EEC from Briggs model x 292 mg food bee -1 day -1 / oral LD50 Larvae: EEC from Briggs model x 120 mg food bee -1 day -1 / LD50 Seed treatment Dietary Adults: 0.29 µg ai/bee / oral LD50 Larvae: 0.12 µg ai/bee / LD50

15 Tier I Risk Quotients (Chronic) Foliar applied Dietary Adults: 32 µg ai/bee x App. rate / 10-d NOEL Larva: 13.2 µg ai/bee x App. rate / NOEL Contact No chronic assessment App. Rate = lbs ai/a Assessment Criteria LOC = 1.0 RQ < 1.0 (Pass) RQ 1.0 (Fail) Soil applied Dietary Adults: EEC from Briggs model x 292 mg food bee -1 day -1 / 10-d NOEL Larvae: EEC from Briggs model x 120 mg food bee -1 day -1 / NOEL Seed treatment Dietary Adults: 0.29 µg ai/bee / 10-d NOEL Larvae: 0.12 µg ai/bee / NOEL

16 Tier I Example: Foliar use of Example AI on cucumbers Assessment Criteria Acute LOC = 0.4 Chronic LOC = 1.0 Acute Dietary Adults: 32 µg ai/bee per 1 lb/a x lb/a /0.005 µg ai/bee = 550 Larva: 13.2 µg ai/bee per 1 lb/a x /13.56 µg ai/bee = PASS Acute Contact Adults: 2.7 µg ai/bee per 1 lb/a x lb/a /0.026 µg ai/bee = 8.93 Chronic Dietary Adults: 32 µg ai/bee per 1 lb/a x lb/a / µg ai/bee = 306 Larva: 13.6 µg ai/bee per 1 lb/a x /0.12 µg ai/bee = 9.75

17 Tier I Example: Foliar use of Example AI on cucumbers Acute refinement using maximum pollen and nectar values 343 ppb (nectar) 1431 ppb (pollen) Acute Dietary Adults: (292 mg/d x 343 ppb) + (0.041 mg/d x 1431 ppb)/0.005 µg ai/bee = 20 Larva: (117 mg/d x 343 ppb + (2.7 mg/d x 1431 ppb) /13.56 µg ai/bee = Assessment Criteria Acute LOC = 0.4 Chronic LOC = 1.0 PASS Acute Contact NA Chronic refinement using maximum daily average pollen and nectar values 170 ppb (nectar) 607 ppb (pollen) Chronic Dietary Adults:(292 mg/d x 170 ppb) + (0.041 mg/d x 607 ppb)/ µg ai/bee = 5.5 Larva: (117 mg/d x 170 ppb + (2.7 mg/d x 607 ppb) /0.12 µg ai/bee = 0.19

18 Tiered Approach Separate decision trees for foliar, soil, seed treatments and tree trunk applications Exposure to adults and brood considered Tier I Acute and chronic toxicity values Estimated exposure estimates Tier II Semi-field (tunnel) studies Feeding studies Residue studies Tier III Full field studies

19 Tier 2 Effects Studies Semi Field Tunnel Studies Hive in tunnel Bee attractive plants Foliar application at bloom Effects observations performed Useful to determine if effects on larvae in laboratory (direct exposure) are evident in the field or result in colony level effects

20 Experimental Design New bee colonies started with package bees with new foundation and hive boxes Bee attractive plants such as buckwheat and canola planted and grown in study area Tunnels set up over crop areas before bloom 5 tunnels for each treatment (UTC and TRT)(one UTC and TRT tunnel used for residue samples), 4 tunnels for bee toxic reference product Hives placed in tunnels 3 days before application of test substance and reference product for acclimation period Test substance and reference product foliar applied at bloom exposure phase (7 days after application) Observe bee mortality, forage, activity and behavior Hives are moved to a monitoring location for colony condition assessments (CCA) and brood mapping assessments for at least two brood cycles (42 days) post exposure Collection of bees, flowers, leaves, and pollen and nectar from hives and possibly plants for analysis

21 Tiered Approach Separate decision trees for foliar, soil, seed treatments and tree trunk applications Exposure to adults and brood considered Tier I Acute and chronic toxicity values Estimated exposure estimates Tier II Semi-field (tunnel) studies Feeding studies Residue studies Tier III Full field studies

22 Tier 2 Effects Studies Feeding studies Spiked sugar solution (nectar) Spiked pollen patties Useful to determine if effects on larvae in laboratory (direct exposure) are evident in the field or result in colony level effects

23 Experimental Design New colonies started with package bees with new foundation and hive boxes Colonies assigned to apiaries based on colony strength but assigned to treatments randomly Honey bee colonies exposed to test substance via sugar solution placed in a feeder inside the hive (top box) Multiple exposure levels (for example 12.5, 25, 50, 75, 100 ppb) Spiked sugar solution added to each hive twice a week for six weeks during nectar dearth Dedicated monitoring hives were used to collect pollen and nectar from combs and pollen from traps for residue analysis and pollen identification Colony condition assessments (CCA) conducted 8 times prior to winter and twice in spring This is an example design Cadillac version simpler designs may be acceptable or use of the Oomen study design

24 Apiary Setup, Locations, and Land use 50 ppb Monitoring 37.5 ppb

25 Conclusions Pollinator data requirements for neonicotinoids are to be completed in While the current focus is on nectar/pollen residue studies to refine the exposure assessment for systemic neonicotinoids, focus of future residue studies will likely shift from seed treatments and soil treatments to foliar applications (including during bloom for fungicides) with data that may be compiled for future risk assessments (e.g., Kenega data). Tier 1 laboratory effects data (chronic adult bee and acute/chronic larval studies) requirements will be the primary focus of pollinator testing. Results of these Tier 1 studies will likely result in additional Tier 2 effects testing (tunnel and/or hive feeding studies) and possibly need for pollen and nectar residue data.

26 6645 Bonus!