Franz Streissl - Bee risk assessment


Published on

Published in: Technology
1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Franz Streissl - Bee risk assessment

  1. 1. Request of the EU Commissionfor 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. 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 and solitary bees).• EFSA-Q-2011-00794: Public consultation on the draft Guidance Document on the Risk Assessment of Plant Protection Products on bees (including Apis mellifera, Bombus spp.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). 2
  3. 3. Bee mandate M-2011-0185Composition 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) 3
  4. 4. Bee mandate M-2011-0185Terms 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. 4
  5. 5. Bee mandate M-2011-0185Chapters of the opinion:1. Introduction2. Specific protection goals3. Exposure4. Chronic toxicity of pesticides in bees after continuous exposure at low (sub-lethal) doses5. 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 effects7. Risk assessment for honeybees, bumblebees and solitary bees8. Conclusions and recommendations 5
  6. 6. Bee mandate M-2011-0185Chapter 2: Specific protection goals (SPG)Follows the approach outlined in the Scientific Opinion of EFSA (2010) onthe definition of specific protection goals.Ecosystem services to protect:1. Pollination2. Food production (hive products)3. Genetic resources and cultural services (education, aesthetic, recreation)Ecological entity:Apis mellifera: colony for all SPGs, foragers for pollinationNon-Apis – population (colonies for bumblebees) 6
  7. 7. Bee mandate M-2011-0185Chapter 2: Specific protection goals (SPGs)Attributes to protect:EU regulation (EC) No 1107/2009 lists acute and chronic effects on thesurvival and development of colonies and effects on larvae and honey beebehaviour as attributes to protect. It is suggested to include alsoabundance/biomass and reproduction because they are important for long-termsurvival 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. 7
  8. 8. WG Bee risk assessmentChapter 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 largefraction of e.g. unexposed hives.95th percentile of the spatio-temporal concentration distribution is used as aworking hypothesis (90th percentiles were accepted in the past but may not beconservative enough). 8
  9. 9. WG Bee risk assessmentChapter 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 chartfor checking whether exposure in semi-field or field study was higher than thecorresponding 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 therisk assessment is carried out• Generation of guttation water in the study compared to reality 9
  10. 10. Bee mandate M-2011-0185Chapter 3: ExposureMajor 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, waxproducing bees, nurse bees, winter bees, drones queens, swarms, larvae),bumblebees (workers, drones, queens, larvae) and solitary bees (adult male, adultfemale, larvae).Information was collected on residues in nectar, pollen, water, honey, beebread, nesting material (wax, propolis, resins), soil and plant surfaces.Based on the information retrieved and expert judgement the most exposedcategories of bees were identified by expert judgement. 10
  11. 11. Bee mandate M-2011-0185Chapter 3: ExposureHoneybees: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 andswarms were most exposed to interception of droplets and vapour (contact andinhalation exposure).Bumblebees:Workers, queens and larvae were most exposed via oral route and also viacontact and inhalation (nest in soil).Solitary bees:Adult females and larvae were most exposed via oral route. Adult and larvaeshow maximum exposure to soil and foliar residues (nesting material). 11
  12. 12. Bee mandate M-2011-0185Chapter 3: ExposureWater consumption was unknown and therefore it was not possible to give anestimate on the relative importance of exposure to residues in water.A potential high exposure to guttation droplets was highlighted for certaincrops (e.g. maize). The potential risk to bees depends on the distance betweenthe colony and the crop and the availability of alternative sources of water andthe frequency (e.g. the risk could be high if a crop is treated with a highly beetoxic compound, the crop shows guttation activity frequently and the colony isclose to the crop). 12
  13. 13. Bee mandate M-2011-0185Chapter 3: ExposureDust drift can lead to relevant exposure during sowing of treated seeds orapplication of granular formulations due to deposition of dust particles on thesoil 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 airexchange.The level of exposure of bees is extremely variable and depends on the qualityof the seed dressing (abrasion), machinery used, number of seeds per ha, time ofsowing, size of the sown area, the vegetation in the margin of the field and on themeteorological conditions. 13
  14. 14. Bee mandate M-2011-0185Chapter 4: Chronic toxicity of pesticides in bees aftercontinuous exposure at low (sub-lethal) dosesConcerns were raised that biologically persistent toxins will have cumulativeeffects that are disproportionate to their short-term manifestations.The conventional regulatory tests are likely to be unsuited to assess the risks oflong-term exposures because they are short-term (48-96 h), which means thatthey could fail to detect the true potential for harm.A new method is proposed to detect cumulative toxicity based on Haber`slaw. 14
  15. 15. Bee mandate M-2011-0185Chapter 4: Chronic toxicity of pesticides in bees aftercontinuous exposure at low (sub-lethal) dosesOverview on the available studies on low doses and long-term effects ofpesticides on bees highlighted gaps in knowledge and future research needs.For honeybees, more studies are required on a wider range of pesticides, onlarvae, on both low-doses and long-term effects (most studies deal with lowdose only), on exposure through contact and inhalation (most studies deal withoral exposure), in field conditions (most studies are conducted under laboratoryconditions) and more studies are needed on endpoints such as biochemical andneurophysiological effects, fecundity and longevity.For non-Apis bees, few studies are available in literature and they involved onlyfew species. The use of micro-colonies in bumblebees appears to be well-suitedto measure lethal and sublethal effects of pesticides with low doses and long-term effects. 15
  16. 16. Bee mandate M-2011-0185Chapter 5: The evaluation of the existing test protocolsLaboratory testsOral 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, alaboratory test on larval toxicity test and precise observations of sublethaleffects (to be included in future risk assessment). 16
  17. 17. Bee mandate M-2011-0185Chapter 5: The evaluation of the existing test protocolsSemi-field testsSemi-field testing follows the test guidelines of EPPO 170(4), OECD 75 (beebrood) and Oomen et al. (1992) test (bee brood).Several weaknesses were identified for each of the guidelines, e.g. the limitedsize of crop area, limited duration of the studies (one brood cycle), difficult toextrapolate results to larger colony sizes.It is recommended to include a more detailed assessment of behaviouraleffects, investigation of sublethal and delayed effects and to develop methodsto investigate in particular systemic compounds including exposure to dust andguttation droplets. Results should be analysed with appropriate statisticalmethods. 17
  18. 18. Bee mandate M-2011-0185Chapter 5: The evaluation of the existing test protocolsField tests for honeybeesField testing follows the guidelines of EPPO 170.Several weaknesses were identified such as the small distance between the hivesand the treated fields, the low surface of the test field, uncertainties with regard tothe real exposure of honeybees. Not enough replicates to conduct a statisticalanalysis.It is recommended to develop guidelines adapted to the specific application ofa substance (e.g. also covering all important exposure routes for seed treatments)and to investigate different effects e.g. homing flight, orientation, foragingbehaviour. The health status of the colonies needs to be assessed, increaseddistance between controls and test fields, test design should allow statisticalanalysis. 18
  19. 19. Bee mandate M-2011-0185Chapter 6: How to take into account of cumulative andsynergistic effectsThis chapter aims to review the evidence of cumulative and synergistic effects ofpesticide mixtures in bees and to develop recommendations for risk assessmentpurposes.At low levels of exposure concentration addition has been observed more oftenthan synergistic or antagonistic effects for mixtures of pesticides with a commonmode of action.Independent action (response addition) has been observed for compounds with adifferent mode of action. 19
  20. 20. Bee mandate M-2011-0185Chapter 6: How to take into account of cumulative andsynergistic effectsThe mechanism of synergistic effects involve inhibition or induction of eitherdetoxification enzymes (cytochrome P-450) or transporters which thenenhancing the toxicity of the mixture.From available literature there is an indication that deviations fromconcentration addition, such as synergy is rarely more than a factor of 2 to 3. 20
  21. 21. Bee mandate M-2011-0185Chapter 7: How to take into account of cumulative andsynergistic effectsIn the case of synergism which can be predicted based on the mode of action ofthe chemicals involved (e.g. EBI fungicides and insecticides) and in the absenceof 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 potentialsynergists to provide a basis to derive benchmark doses and their limit assuggested by EFSA`s scientific committee.There is growing evidence that there are interactions between bee diseases andpesticide effects. Further work is required to identify the molecular basis ofinteractions between environmentally realistic exposure to pesticides and therange of honeybee diseases to determine whether and how these may be includedin the risk assessment. 21
  22. 22. Bee mandate M-2011-0185Chapter 7: Risk assessment for honeybees, bumblebees andsolitary beesTwo new risk assessment schemes are proposed, one for honeybees and one forbumblebees and solitary bees.The most important exposure routes are covered:Exposure of foragers by spray or dust by contact or oral intake, exposure ofall adult bees and larvae from exposure to residues in pollen, nectar orguttation droplets.Toxicity testing over longer exposure period for adult bees and larvae isincluded in the first tier.Investigation of cumulative effects. 22
  23. 23. Bee mandate M-2011-0185Chapter 7: Risk assessment for honeybees, bumblebees andsolitary beesA 7 day laboratory larvae test (Aupinel) is always required. The Oomen test isrequired if the LD50 for adult bees is below 100 µg/bee or the laboratory larvaetest gives an indication of cumulative toxicity. The Oomen test integrates broodcare behaviour of adult bees. The lower endpoint of both tests should be used inthe scheme.The scheme for bumblebees and solitary bees is based on less well definedsteps and toxicity tests. The scheme uses data for honey bees as a surrogateinput. The development of standardized contact and oral toxicity test, semi fieldand field tests for bumblebees and solitary bees has yet to be completed and ringtested. 23
  24. 24. Bee mandate M-2011-0185Timelines:Opinion to be issued by April 2012Guidance Document to be issued by December 2012Public consultation on draft GD:July 2012 – September 2012 24
  25. 25. Bee mandate M-2011-0185Thank you for your attention! Questions 25