EFSA Guidance Document on the Risk Assessment of Plant Protection Products on bees (Apis mellifera, Bombus spp. and solitary bees)

Transcription

1 EFSA Guidance Document on the Risk Assessment of Plant Protection Products on bees (Apis mellifera, Bombus spp. and solitary bees) Csaba Szentes, EFSA 16/10/2013, SETAC, SESSS08

2 Bee mandate M Scientific Opinion on the science behind the development of a GD was issued in May Public consultation on draft GD: October-November 2012 and February-March Guidance Document was issued in July

3 Members of the working group Gérard Arnold, National Centre of Scientific Research, France Jos Boesten, Alterra, The Netherlands Mark Clook, CRD, United Kingdom Robert Luttik (chair), independent environmental scientist, formerly RIVM, NL, Member of the Scientific Committee of the EFSA Fabio Sgolastra, University of Bologna, Italy Jacoba Wassenberg, CTGB, The Netherlands Hearing expert: Jens Pistorius, Julius Kühn Institute, Germany Franz Streissl, EFSA, Pesticide Unit, Secretariat of working group Csaba Szentes, EFSA, Pesticide Unit Maria Arena, EFSA, Seconded national expert Agnes Rortais, EFSA, Scientific Committee and Emerging Risks Unit Olaf Mosbach-Schulz, EFSA, Scientific Assessment Support Unit 3

4 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. 4

5 Specific Protection Goal (SPG) Ecosystem services to protect: 1. Pollination 2. Food production (hive products) 3. Genetic resources and cultural services (education, aesthetic, recreation) 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. 5

6 Specific Protection Goal (SPG) The viability of each colony, the pollination services it provides, and its yield of hive products all depend on the colony s strength. Therefore special focus on impacts on colony strength. The magnitude of impact on colony sizes was defined as: Effect Magnitude (reduction in colony size) Large >35% Medium 15 % to 35% Small 7% to 15% Negligible 3.5 % to 7% 6

7 Specific Protection Goal (SPG) The model of Khoury et al. (2011) was used to translate effects on colony size into forager mortality. Multiple of background mortality of forager bees Negligible effect Reduction of colony size by 7% Small effect Reduction of colony size by 15% Medium effect Reduction of colony size by 35% Viable after 50 days? 1.5 (m = 0.231) 6 days 13 days 40 days Yes 2 (m = 0.308) 3 days 7 days 18 days Yes 3 (m = 0.462) 2 days 4 days 10 days No 7

8 Specific Protection Goal (SPG) It was agreed in the SCoFCAH to base the specific protection goal on a negligible effect on colonies. The exposure assessment goal was defined as 90 th percentile worst-case considering colonies at edges of treated fields in area of use of the substance. The risk assessment scheme and associated trigger values enable an assessment that, if met, would ensure that exposure does not exceed a value that could lead to effects which are more than negligible in 90 % of sites (i.e. treated fields) where honey bee colonies are situated on the edge of treated fields. 8

9 Toxicity endpoints needed Acute oral toxicity to adults, expressed as µg/bee (LD50) Acute contact toxicity to adults, expressed as µg/bee (LD50) Chronic oral toxicity to adults (including an assessment of the effects on the hypophanygeal gland), expressed as µg/bee/day (at LC50 or NOEC level for HPG) Toxicity to larvae, expressed as µg/larvae/development period (at NOEC) Consideration of potential accumulative effects 9

10 Routes of exposure Exposure via contact either from spray deposits (i.e. overspray or spray drift) or from dust particles Consumption of pollen Consumption of nectar Consumption of water (i.e. guttation fluid, surface water and puddles) Risk from metabolites (pollen & nectar) but the exposure routes to honeydew and soil are not addressed 10

11 Routes of exposure Bees can be exposed differently by visiting different plants in the agricultural landscape. The assessment is focused on the following plant categories: treated crop (overspray/dust; root uptake) weeds in the field (overspray/dust) plants in field margins (spray drift/dust drift) adjacent crop (spray drift/dust drift) succeeding crop (root uptake) 11

12 Contact exposure assessment Spray applications Linked with the mass of substance to which forager bees are exposed when over-sprayed (data from field measurements) photo by Dick Belgers 0.85 cm 2 1 cm Solid formulations No measured data for dust (on bees) were available, therefore data from spray were used with a safety factor contact with of 3 (dust is longer available and 12 may stick to hairs of foragers) pollen: also dust may stick to bees

13 Oral exposure assessment Linked with the residues in nectar and pollen entering the hive spray applications seed treatments granule applications Three different exposure characterisation for different application techniques Exposure flow charts for each plant category some flow charts are identical for sprays, seed treatments and granules: e.g. for succeeding annual crops 13

14 The risk assessment schemes There are three separate RA schemes (contact & oral): Honey bee sprays solids (seed treatments, granules) Bumble bee Solitary bee sprays solids (seed treatments, granules) sprays solids (seed treatments, granules) Additional separate schemes for water consumption and for the metabolites 14

15 The risk assessment schemes The following values for risk characterisation will be calculated: HQ (Hazard Quotient) for contact risk ETR (Exposure Toxicity Ratio) for oral risk The equations are: Exposure HQ = AR x fdep/ld50 ETR = AR x Ef x SV x twa/tox.endpoint Where: Hazard AR = application rate fdep = deposition factor Ef = exposure factor SV = shortcut value twa = time weighted average 15

16 Trigger values The trigger values for the adults (acute and chronic scenarios) were mathematically derived considering the natural background mortality (e.g. 5.3% daily mortality for honey bees) and the still acceptable mortality (maximum increment above background level) caused by the pesticide application as defined by the specific protection goal (as discussed earlier). Larval toxicity and effects on hypopharyngeal glands could not be quantitatively linked to the protection goals. Therefore it was decided to use NOECs as endpoints assuming that no effects are to be expected at colony level. 16

17 Trigger values In order to account for potential differences in subspecies and lab. to field extrapolation, an assessment factor of 5 was added to the trigger for larvae. Also, a factor of 5 was added to the triggers for bumble bees and solitary bees in order to account for the higher susceptibility to forager loss (for BB) and the potential differences in sensitivity between species. When honey bee endpoints are used for bumble bees and solitary bees an assessment factor of 10 was proposed. Andrena erythronii Apis cerana Apis florea Bombus agrorum Bombus lapidarius Bombus lucorum Bombus terrestris Bombus terricola Megachile rotundata Melipona beecheii Melipona scutellaris Nannotrigona perilampoides Nomia melanderi Osmia lignaria Scaptotrigona postica Trigona irridipenis Trigona nigra Trigona spinipes 4.8% Ratio 17

18 Trigger values Endpoint Honey bees Bumble bees Solitary bees Acute contact LD50 downward spray upward/sideward spray HQ <42 HQ <85 HQ <7 HQ <14 HQ <8 HQ <16 Acute oral LD50 ETR <0.2 ETR <0.036 ETR <0.04 Chronic oral LC50 ETR <0.03 ETR < ETR < Larval toxicity NOEC ETR <0.2 ETR <0.2 ETR <0.2 Development hypopharyngeal glands ETR <

19 Trigger values Future refinements of first tier trigger values will be possible once more information becomes available on: Background mortality rates of foragers Larvae mortality and effects on colony size Effects on development of HPG and colony size Specie sensitivity distribution for bumble bees and solitary bees Calibration of trigger values with field studies 19

20 Higher tier options When lower tiers fail: Risk mitigation Classical elements e.g. do not spray when New elements like: use special spray nozzles or use deflector when sowing Exposure refinement A large set of elements can be refined e.g.: Residue levels Dust deposition Sugar content Etc. Effect refinement Field studies Semi-field studies 20

21 Field studies If field studies are conducted then the following key issues need to be considered: appropriate exposure; so residue measurements from bees (from bee surface or honey sack/pollen load) are needed and compared with measurements from pre-studies appropriate design/replication so that it can be determined that the specific protection goal is met

22 Analysis of uncertainty Working example: Source of uncertainty Potential to make true risk lower Explanation Potential to make true risk higher Explanation Exposure studies +++ All studies conducted according to the Guidance Document, i.e. an appropriate range of soil/climate conditions. Studies submitted to determine dilution factor are acceptable. Exposure in field studies Effects in field studies Overall assessment +++ Exposure in field studies were in line with that determined to occur as a result of residue studies. In-field measurements of foraging and pollen identification indicate adequate exposure as well. +++ Demonstration that bees were exposed to at least a 90 th percentile, colonies were healthy and monitored throughout. - True exposure is unlikely to be worst. True risk is unlikely to be worst than this as in reality dilution due to adjacent crops and flowering weeds will occur. - Only potential issue is that different strains of bees may react differently from those selected. Underlying studies are in line with those recommended and as a result uncertainties minimal and would indicate that the true risk is lower than that assessed. 22

23 Thank you for your attention! 23

24 Summary of the overall pass rates (EFSA s impact analysis) Overall pass rates of standard lower tier assessments 24 insecticidal uses, 16 fungicidal uses and 21 herbicidal uses Insecticides Fungicides Herbicides Acute contact 37.5 % 100 % 100 % Acute oral 37.5 % 100 % 100 % Chronic oral 29.2 % 56.2 % 23.8 %

25 Summary of the overall pass rates (EFSA s impact analysis) Overall pass rates of standard lower tier assessments without weeds in field scenario 24 insecticidal uses, 16 fungicidal uses and 21 herbicidal uses Insecticides Fungicides Herbicides Acute contact 37.5 % 100 % 100 % Acute oral 37.5 % 100 % 100 % Chronic oral 29.2 % 56.2 % 66.6 %