This document discusses the EU Commission's request for EFSA to provide a scientific opinion and guidance on risk assessment of plant protection products (pesticides) on bees. It outlines the composition of the working group, terms of reference, and proposed chapters to cover introduction, protection goals, exposure assessment, chronic toxicity from low doses, test methods, cumulative/synergistic effects, and risk assessment methodology for honeybees, bumblebees and solitary bees. It provides details on the key sections including identifying the most exposed bee categories and life stages, major exposure routes, and proposing a new method to assess cumulative toxicity from long-term low exposures.

1. Request of the EU Commission
for an Opinion on the science behind the development
of a risk assessment of PPPs on bees (Apis mellifera
Bombus spp. and solitary bees)
and to prepare an EFSA Guidance on the risk
assessment of PPPs on bees.
ECPA-IBMA workshop – EFSA evaluation of PPPs
26 April 2012 1

2. Bee mandate M-2011-0185
• EFSA-Q-2011-00417: Scientific Opinion on the science behind the
development of a Risk Assessment of Plant Protection Products on
bees (Apis mellifera, Bombus spp. and solitary bees).
• EFSA-Q-2011-00418: Guidance Document on the Risk Assessment
of Plant Protection Products on bees (including Apis mellifera,
Bombus spp. and solitary bees).
• EFSA-Q-2011-00794: Public consultation on the draft Guidance
Document on the Risk Assessment of Plant Protection Products on
bees (including Apis mellifera, Bombus spp. and solitary bees).
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3. Bee mandate M-2011-0185
Composition of the working group:
• 4 members of PPR Panel (expertise in pesticide risk assessment,
uncertainty analysis, fate and behaviour of pesticides, probabilistic risk
asessment)
• 4 experts in honeybee biology (one beekeeper) (expertise in all aspects
of honeybee biology, test methods, exposure, monitoring)
• 2 experts in bumblebee and solitary bee biology (expertise in all aspects
of non-Apis bee biology, monitoring, test methods)
• 1 hearing expert from Industry (only invited to give information to the
group but no active involvement)
• 4 EFSA staff members (expertise in pesticide risk assessment, bee
biology/behaviour, toxicology)
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4. Bee mandate M-2011-0185
Terms of reference:
• The Guidance Document should address the risk to Apis mellifera,
Bombus spp and to solitary bees.
• The assessment of the acute and chronic effects of Plant Protection
Products on bees, including the colony survival and development.
• The estimation of the long term effects due to exposure to low
concentrations.
• The development of a methodology to take into account cumulative and
synergistic effects.
• The evaluation of the existing validated test protocols and the possible
need to develop new protocols, especially to take into account the
exposure of bees to pesticides through nectar and pollen.
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5. Bee mandate M-2011-0185
Chapters of the opinion:
1. Introduction
2. Specific protection goals
3. Exposure
4. Chronic toxicity of pesticides in bees after continuous
exposure at low (sub-lethal) doses
5. The evaluation of the existing test protocols for honeybees,
social non-Apis (bumblebees) and solitary bees
(laboratory/semi-field/field)
6. How to take into account cumulative and synergistic effects
7. Risk assessment for honeybees, bumblebees and solitary
bees
8. Conclusions and recommendations 5

6. Bee mandate M-2011-0185
Chapter 2: Specific protection goals (SPG)
Follows the approach outlined in the Scientific Opinion of EFSA (2010) on
the definition of specific protection goals.
Ecosystem services to protect:
1. Pollination
2. Food production (hive products)
3. Genetic resources and cultural services (education, aesthetic, recreation)
Ecological entity:
Apis mellifera: colony for all SPGs, foragers for pollination
Non-Apis – population (colonies for bumblebees)
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7. Bee mandate M-2011-0185
Chapter 2: Specific protection goals (SPGs)
Attributes to protect:
EU regulation (EC) No 1107/2009 lists acute and chronic effects on the
survival and development of colonies and effects on larvae and honey bee
behaviour as attributes to protect. It is suggested to include also
abundance/biomass and reproduction because they are important for long-term
survival of the colony.
Magnitude of effects:
Small effects on foragers in field (in the range of days), negligible effects off-
field, negligible effects on colonies (at the field edge).
Exposure assessment goals:
The overall level of protection includes also the exposure assessment goal.
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8. WG Bee risk assessment
Chapter 2: Specific protection goals (SPGs)
Exposure assessment goals:
Consider each of the regulatory zones as the total area for all SPGs.
Focus on the field scale to avoid “dilution” of the spatial population with a large
fraction of e.g. unexposed hives.
95th percentile of the spatio-temporal concentration distribution is used as a
working hypothesis (90th percentiles were accepted in the past but may not be
conservative enough).
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9. WG Bee risk assessment
Chapter 2: Specific protection goals (SPGs)
Exposure assessment goals:
Current risk assessment relies on HQ approach and semi-field and field tests.
Difficult to ascertain that a specific exposure percentile is achieved. Flow chart
for checking whether exposure in semi-field or field study was higher than the
corresponding 95th percentile. These main factors could include:
• Crop and development stage in study in relation to agricultural reality
• Dosage in study and in reality
• Measures taken in the study to ensure exposure
• Location and weather conditions in the study compared to zone for which the
risk assessment is carried out
• Generation of guttation water in the study compared to reality
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10. Bee mandate M-2011-0185
Chapter 3: Exposure
Major exposure routes (oral, contact, inhalation) were identified for honeybees,
bumblebees and solitary bees for sprayed, non-sprayed (systemic and non-
systemic) substances and for soil fumigants.
Information was collected on consumption of nectar, pollen, water,
interception of droplets of different life stages of honeybees (foragers, wax
producing bees, nurse bees, winter bees, drones queens, swarms, larvae),
bumblebees (workers, drones, queens, larvae) and solitary bees (adult male, adult
female, larvae).
Information was collected on residues in nectar, pollen, water, honey, bee
bread, nesting material (wax, propolis, resins), soil and plant surfaces.
Based on the information retrieved and expert judgement the most exposed
categories of bees were identified by expert judgement.
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11. Bee mandate M-2011-0185
Chapter 3: Exposure
Honeybees:
Foraging bees, winter bees and larvae were most exposed via the oral route.
Larvae were most exposed to residues in wax and foragers, drones, queens and
swarms were most exposed to interception of droplets and vapour (contact and
inhalation exposure).
Bumblebees:
Workers, queens and larvae were most exposed via oral route and also via
contact and inhalation (nest in soil).
Solitary bees:
Adult females and larvae were most exposed via oral route. Adult and larvae
show maximum exposure to soil and foliar residues (nesting material).
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12. Bee mandate M-2011-0185
Chapter 3: Exposure
Water consumption was unknown and therefore it was not possible to give an
estimate on the relative importance of exposure to residues in water.
A potential high exposure to guttation droplets was highlighted for certain
crops (e.g. maize). The potential risk to bees depends on the distance between
the colony and the crop and the availability of alternative sources of water and
the frequency (e.g. the risk could be high if a crop is treated with a highly bee
toxic compound, the crop shows guttation activity frequently and the colony is
close to the crop).
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13. Bee mandate M-2011-0185
Chapter 3: Exposure
Dust drift can lead to relevant exposure during sowing of treated seeds or
application of granular formulations due to deposition of dust particles on the
soil in the field, soil and plants outside the field, on puddles in the field,
interception of particles by flying bees, particles entering the hive via air
exchange.
The level of exposure of bees is extremely variable and depends on the quality
of the seed dressing (abrasion), machinery used, number of seeds per ha, time of
sowing, size of the sown area, the vegetation in the margin of the field and on the
meteorological conditions.
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14. Bee mandate M-2011-0185
Chapter 4: Chronic toxicity of pesticides in bees after
continuous exposure at low (sub-lethal) doses
Concerns were raised that biologically persistent toxins will have cumulative
effects that are disproportionate to their short-term manifestations.
The conventional regulatory tests are likely to be unsuited to assess the risks of
long-term exposures because they are short-term (48-96 h), which means that
they could fail to detect the true potential for harm.
A new method is proposed to detect cumulative toxicity based on Haber`s
law.
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15. Bee mandate M-2011-0185
Chapter 4: Chronic toxicity of pesticides in bees after
continuous exposure at low (sub-lethal) doses
Overview on the available studies on low doses and long-term effects of
pesticides on bees highlighted gaps in knowledge and future research needs.
For honeybees, more studies are required on a wider range of pesticides, on
larvae, on both low-doses and long-term effects (most studies deal with low
dose only), on exposure through contact and inhalation (most studies deal with
oral exposure), in field conditions (most studies are conducted under laboratory
conditions) and more studies are needed on endpoints such as biochemical and
neurophysiological effects, fecundity and longevity.
For non-Apis bees, few studies are available in literature and they involved only
few species. The use of micro-colonies in bumblebees appears to be well-suited
to measure lethal and sublethal effects of pesticides with low doses and long-
term effects. 15

16. Bee mandate M-2011-0185
Chapter 5: The evaluation of the existing test protocols
Laboratory tests
Oral and contact exposure of adult bees following OECD 213 and 214 guidelines.
Intermittent and prolonged exposure of adults and larvae testing is not included.
It is recommended in the first tier to include chronic testing of adult bees, a
laboratory test on larval toxicity test and precise observations of sublethal
effects (to be included in future risk assessment).
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17. Bee mandate M-2011-0185
Chapter 5: The evaluation of the existing test protocols
Semi-field tests
Semi-field testing follows the test guidelines of EPPO 170(4), OECD 75 (bee
brood) and Oomen et al. (1992) test (bee brood).
Several weaknesses were identified for each of the guidelines, e.g. the limited
size of crop area, limited duration of the studies (one brood cycle), difficult to
extrapolate results to larger colony sizes.
It is recommended to include a more detailed assessment of behavioural
effects, investigation of sublethal and delayed effects and to develop methods
to investigate in particular systemic compounds including exposure to dust and
guttation droplets. Results should be analysed with appropriate statistical
methods.
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18. Bee mandate M-2011-0185
Chapter 5: The evaluation of the existing test protocols
Field tests for honeybees
Field testing follows the guidelines of EPPO 170.
Several weaknesses were identified such as the small distance between the hives
and the treated fields, the low surface of the test field, uncertainties with regard to
the real exposure of honeybees. Not enough replicates to conduct a statistical
analysis.
It is recommended to develop guidelines adapted to the specific application of
a substance (e.g. also covering all important exposure routes for seed treatments)
and to investigate different effects e.g. homing flight, orientation, foraging
behaviour. The health status of the colonies needs to be assessed, increased
distance between controls and test fields, test design should allow statistical
analysis.
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19. Bee mandate M-2011-0185
Chapter 6: How to take into account of cumulative and
synergistic effects
This chapter aims to review the evidence of cumulative and synergistic effects of
pesticide mixtures in bees and to develop recommendations for risk assessment
purposes.
At low levels of exposure concentration addition has been observed more often
than synergistic or antagonistic effects for mixtures of pesticides with a common
mode of action.
Independent action (response addition) has been observed for compounds with a
different mode of action.
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20. Bee mandate M-2011-0185
Chapter 6: How to take into account of cumulative and
synergistic effects
The mechanism of synergistic effects involve inhibition or induction of either
detoxification enzymes (cytochrome P-450) or transporters which then
enhancing the toxicity of the mixture.
From available literature there is an indication that deviations from
concentration addition, such as synergy is rarely more than a factor of 2 to 3.
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21. Bee mandate M-2011-0185
Chapter 7: How to take into account of cumulative and
synergistic effects
In the case of synergism which can be predicted based on the mode of action of
the chemicals involved (e.g. EBI fungicides and insecticides) and in the absence
of data on the toxicity of the mixture it is recommended to design full dose-
response studies in adult bees and larvae for these mixtures of potential
synergists to provide a basis to derive benchmark doses and their limit as
suggested by EFSA`s scientific committee.
There is growing evidence that there are interactions between bee diseases and
pesticide effects. Further work is required to identify the molecular basis of
interactions between environmentally realistic exposure to pesticides and the
range of honeybee diseases to determine whether and how these may be included
in the risk assessment.
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22. Bee mandate M-2011-0185
Chapter 7: Risk assessment for honeybees, bumblebees and
solitary bees
Two new risk assessment schemes are proposed, one for honeybees and one for
bumblebees and solitary bees.
The most important exposure routes are covered:
Exposure of foragers by spray or dust by contact or oral intake, exposure of
all adult bees and larvae from exposure to residues in pollen, nectar or
guttation droplets.
Toxicity testing over longer exposure period for adult bees and larvae is
included in the first tier.
Investigation of cumulative effects.
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23. Bee mandate M-2011-0185
Chapter 7: Risk assessment for honeybees, bumblebees and
solitary bees
A 7 day laboratory larvae test (Aupinel) is always required. The Oomen test is
required if the LD50 for adult bees is below 100 µg/bee or the laboratory larvae
test gives an indication of cumulative toxicity. The Oomen test integrates brood
care behaviour of adult bees. The lower endpoint of both tests should be used in
the scheme.
The scheme for bumblebees and solitary bees is based on less well defined
steps and toxicity tests. The scheme uses data for honey bees as a surrogate
input. The development of standardized contact and oral toxicity test, semi field
and field tests for bumblebees and solitary bees has yet to be completed and ring
tested.
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24. Bee mandate M-2011-0185
Timelines:
Opinion to be issued by April 2012
Guidance Document to be issued by December 2012
Public consultation on draft GD:
July 2012 – September 2012
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25. Bee mandate M-2011-0185
Thank you for your attention!
Questions
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