# Exposure of Honey Bees t o Pe st icides and the Re la tive Import ance of the Iden tified Exposure Ro ut es **1** U.S. Environmental Pr otection Agency


### Chris tina We ndel, M.S. Environmental F ate and E ffects Division Office of P es ticide Pr ogr ams

# Outline
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### Discussion of the potential e xposur e r outes/pathwa ys by application type and age of the bee (adult work er vs. lar va e) • Foliar Applications • Soil Applications & Seed Tre at ments U.S. Environmental Pr otection Agency **2**

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### Exposur e pathwa ys consider ed and included in the Tier I ex posur e assessmen t
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### Exposur e pathwa ys consider ed but not included in the Tier I ex posur e assessmen t

# Po te nt ial Exposure Ro ut es fo r Honey Bees
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### Con ta ct • Dir ect spr ay

, contaminated foliage and soil, dus t, comb w ax, pr opolis , and/ or pollen
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### Or al U.S. Environmental Pr otection Agency **3**

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### Or al • Dietary • Po llen, nect ar

, honey , bee br ead, r oyal jelly

, and/ or br ood food • Drinking wate r • Po nds, puddles, dew

, and/ or gut tation fluid • 

### Inhalation • Spr ayd ro plets, and/ or v olatiliz ed chemical

# Fo liar Spray

A pplic at ions – Exposure Ro ut es U.S. Environmental Pr otection Agency **4 Con**  **ta ct:**  Dir ect spr ay **Or al:**  Collection

and c onsumption 

## Adult Fo ra ger Bees **Inhala tion:**  Spr ay dr oplets or **Con ta**  **ct:** With c on ta minated

fo liag e, soil, c omb w ax, pr opolis and/ or pollen **Or al:**  Collection and c onsumption of c on ta minated pollen, nect ar

, and/ or drinking water dr oplets or ga seous phase of chemic al

# Fo liar Spray

A pplic at ions – Exposure Ro ut es U.S. Environmental Pr otection Agency **5**
**Or al:**  Pr ocessing and c onsumption 

## Hive Bees (Adults and Larv ae) **Inhala tion:**  **Con ta**  **ct:** With c on ta minated

co mb wax, pr opolis and/ or pollen **Or al:**  Pr ocessing and c onsumption of c on ta minated pollen, nect ar

, and/ or drinking water **Inhala tion:**  Gaseous phase of chemic al

# Soil and Seed Trea tmen t Applic at ions – Exposure Ro ut es U.S. Environmental Pr otection Agency **6**
**Or al:**  Collecting, pr ocessing, and 

## Fo ra ger bees and in hiv e bees (adults and larv ae) **Inhala tion:**  **Con ta**  **ct:** With c on ta minated

dust, comb wax, pr opolis and/ or pollen **Or al:**  Collecting, pr ocessing, and co nsumption of co nta minated pollen, nect ar

, and/ or drinking water **Inhala tion:**  Gaseous phase of chemic al

# Exposure Pa thw ays in the Tier I Screen • 

### Con **ta ct with**  • **Dir ect spr** **ay**, • **Contaminated fo**  **liag e, soil, comb w**  **ax ,**  **pr opolis**  **, and/** **or pollen** • **Dust** • 

### Or**al** U.S. Environmental Pr otection Agency **7**

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### Or**al** • **Dietary** • **Po llen,**  **nect ar**  • **Hone y,**  **b ee br**  **ead, r oy** **al jelly , and/** **or br ood**  **fo od**  • **Drinking w ate**  **r** • **Po nds,**  **puddles, dew**

**, and/ or guttation**  **fluid** • 

### Inhalation • **Spr ay** **dr oplets, and/** **or g aseous phase of a vola**  **tiliz ed chemical** 

# Con ta ct Exposure - Dust
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### Po te nt ial major r oute of e xposur e for some pes ticides and application scenarios
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### Inciden ts of bee mortality re lated to dust exposur e U.S. Environmental Pr otection Agency **8**

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### Ra tionale of not including this e xposur e r oute into Tier I scr een fo r all pes ticides • Ef fe ctiv e quantitative scr eening t ool is not curr ently a va ilable • St ewardship Pr ogr ams • Management of e xposur e thr ough mitig at ion • BMP ’s • Seed coating t echnologies • Alt ernative lubricating agents to talc and/ or gr aphit e

# Oral Exposure – Drinking Wa te r
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### Compar ed potential doses r eceiv ed thr ough contact (dir ect spr ay ) and or al (dietary) ve rs us contaminated drinking water
• Po nds and Puddles • Discountable relative to contact and dietary r out es of e xposur e U.S. Environmental Pr otection Agency **9**

• Discountable relative to contact and dietary r out es of e xposur e • Dew and Gut tation fluid • Po tentially significant based on conser vat iv e assumptions • In ve st ig ated further

# Dew and Guttat ion Fluid Exposur es ar e not e xpect ed to be as significant when compar ed to diet because of two primary r easons 1. Time of da y when a va ilable vs. for aging times for bees U.S. Environmental Pr otection Agency **10**

2. Consumption r ates fr om w ater vs. food

### Estimat**ed amoun** **ts of**  **wate r consumed fr**  **om fo**  **od fo**  **r adult bees Wo**  **rk er**  **Ta sk**  **Honey Nect**  **ar Pe**  **rc ent daily water flux**  **consumed with f** **ood Pe**  **rc ent daily water flux**  **consumed with f** **ood Cell cleaning and capping**  8% 84% **Br ood and queen t**  **ending** U.S. Environmental Pr otection Agency **11**

**Br ood and queen t**  **ending (nurse bees)**  22% 234% **Comb building , cleaning**  **and f ood**  **handling** 8% 84% **For aging (pollen)**  7% 73% **For aging (nect**  **ar)** 38% 409%

# Inhala tion Exposure
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### Highly volatile pesticides • i.e., fumig ants • 

### Fo liar and Soil applications • Not relevant for seed tr eatment applications U.S. Environmental Pr otection Agency **12**

• Not relevant for seed tr eatment applications
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### Hiv es in close pr ox imity to tr ea te d site
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### Curr en tly ev aluating the inhalation e xposur e pathwa y. Pr eliminary re sults sugg es t that e xposur e fr om inhalation is substantially lower than the dietary or contact e xposur e.

# Summary of P at hw aysC onsidered
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### Fo cused on r outes that cr ea te the most substantial exposur es
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### Primary (major) ro utes of e xposur e: • **Contact -**  **via dir ect spr** **ay**, contact with contaminated dust – on a case by case basis U.S. Environmental Pr otection Agency **13**

• **Or al**  **- via P**  **ollen and Nectar** (assumed t o be pr otectiv e of honey , bee br ead, r oyal jelly

, br ood food) • 

### Other r outes of e xposur e: • Contact via contact with contaminated foliage, soil, comb w ax, pr opolis , and/ or pollen • Or al via consumption of contaminated drinking w ater • Inhala tion