Conclusion on the peer review of the pesticide risk assessment of the active substance metaldehyde 1

Transcription

1 CONCLUSION ON PESTICIDE PEER REVIEW Conclusion on the peer review of the pesticide risk assessment of the active substance metaldehyde 1 SUMMARY European Food Safety Authority 2 European Food Safety Authority (EFSA), Parma, Italy Metaldehyde is one of the 79 substances of the third stage part A of the review programme covered by Commission Regulation (EC) No 1490/2002 3, as amended by Commission Regulation (EC) No 1095/ In accordance with the Regulation, at the request of the Commission of the European Communities (hereafter referred to as the Commission ), the EFSA organised a peer review of the initial evaluation, i.e. the Draft Assessment Report (DAR), provided by Austria, being the designated rapporteur Member State (RMS). The peer review process was subsequently terminated following the applicant s decision, in accordance with Article 11e, to withdraw support for the inclusion of metaldehyde in Annex I to Council Directive 91/414/EEC. Following the Commission Decision of 5 December 2008 (2008/934/EC) 5 concerning the noninclusion of metaldehyde in Annex I to Council Directive 91/414/EEC and the withdrawal of authorisations for plant protection products containing that substance, the applicant Lonza GmbH made a resubmission application for the inclusion of metaldehyde in Annex I in accordance with the provisions laid down in Chapter III of Commission Regulation (EC) No. 33/ The resubmission dossier included further data in response to the issues identified in the DAR. In accordance with Article 18 of Commission Regulation (EC) No. 33/2008, Austria, being the designated RMS, submitted an evaluation of the additional data in the format of an Additional Report. The Additional Report was received by the EFSA on 5 January 2010 In accordance with Article 19 of Commission Regulation (EC) No. 33/2008, the EFSA distributed the Additional Report to Member States and the applicant for comments on 7 January The EFSA collated and forwarded all comments received to the Commission on 22 February 2010 In accordance with Article 20, following consideration of the Additional Report, the comments received, and where necessary the DAR, the Commission requested the EFSA to conduct a focused peer review in the areas of mammalian toxicology and ecotoxicology and to deliver its conclusions on metaldehyde. The conclusions laid down in this report were reached on the basis of the evaluation of the representative uses of metaldehyde as a molluscicide in cereals (rye, oat, wheat, barley, and triticale) 1 On request from the European Commission, Question No EFSA-Q , issued on 11 October Correspondence: praper@efsa.europa.eu 3 OJ L224, , p.25 4 OJ L 246, , p OJ L 333, , p.11 6 OJ L 15, , p.5 Suggested citation: European Food Safety Authority; Conclusion on the peer review of the pesticide risk assessment of the active substance metaldehyde.. [71 pp.]. doi: /j.efsa Available online: European Food Safety Authority,

2 and oilseed rape, as proposed by the applicant. Full details of the representative uses can be found in Appendix A. No area of concern or data gap was identified in the physical chemical properties section. No area of concern or data gap was identified in the mammalian toxicology section. For residues there are no critical areas of concern and the risk assessment is finalised. The data available on environmental fate and behaviour are sufficient to carry out the required environmental exposure assessments at the EU level, for the representative uses assessed, however it should be noted that the assessment is specific to the particular formulated product Metarex only. It is therefore inappropriate to extrapolate the environmental exposure assessment presented to any other products containing metaldehyde. The potential for groundwater exposure by metaldehyde, from the representative uses of the formulated product Metarex in cereals and spring sown oilseed rape, above the parametric drinking water limit of 0.1 µg/l was concluded to be low in geoclimatic situations that are represented by all the pertinent FOCUS groundwater scenarios (up to 9). For the representative use of Metarex on autumn sown (winter) oilseed rape, the modelling results for 5 out of the 6 FOCUS groundwater scenarios indicated a low potential for groundwater exposure above 0.1 µg/l. Under the geoclimatic conditions represented by the Piacenza scenario, contamination of groundwater by parent metaldehyde above 0.1 µg/l cannot be excluded. A high acute and long-term risk was assessed for birds and mammals. A data gap was identified to provide new acute and long-term risk assessments for birds from all routes of exposure for all representative uses. Moreover, a data gap was identified to provide a new acute and long-term risk assessment for granivorous mammals for all representative uses. The risk to other non-target organisms was assessed as low. KEY WORDS Metaldehyde, peer review, risk assessment, pesticide, molluscicide 2

3 TABLE OF CONTENTS Summary... 1 Table of contents... 3 Background... 4 The active substance and the formulated product... 6 Conclusions of the evaluation Identity, physical/chemical/technical properties and methods of analysis Mammalian toxicity Residues Environmental fate and behaviour Ecotoxicology Overview of the risk assessment of compounds listed in residue definitions triggering assessment of effects data for the environmental compartments Soil Ground water Surface water and sediment Air List of studies to be generated, still ongoing or available but not peer reviewed Particular conditions proposed to be taken into account to manage the risk(s) identified Issues that could not be finalised Critical areas of concern References Appendices Abbreviations

4 BACKGROUND Legislative framework Commission Regulation (EC) No 1490/2002 7, as amended by Commission Regulation (EC) No 1095/ lays down the detailed rules for the implementation of the third stage of the work programme referred to in Article 8(2) of Council Directive 91/414/EEC. This regulates for the European Food Safety Authority (EFSA) the procedure for organising, upon request of the Commission of the European Communities (hereafter referred to as the Commission ), a peer review of the initial evaluation, i.e. the Draft Assessment Report (DAR), provided by the designated rapporteur Member State. Commission Regulation (EC) No 33/ lays down the detailed rules for the application of Council Directive 91/414/EEC for a regular and accelerated procedure for the assessment of active substances which were part of the programme of work referred to in Article 8(2) of Council Directive 91/414/EEC but which were not included in Annex I. This regulates for the EFSA the procedure for organising the consultation of Member States and the applicant(s) for comments on the Additional Report provided by the designated RMS, and upon request of the Commission the organisation of a peer review and/or delivery of its conclusions on the active substance. Peer review conducted in accordance with Commission Regulation (EC) No 1490/2002 Metaldehyde is one of the 79 substances of the third stage part A of the review programme covered by Commission Regulation (EC) No 1490/2002, as amended by Commission Regulation (EC) No 1095/2007. In accordance with the Regulation, at the request of the Commission, the EFSA organised a peer review of the DAR provided by the designated rapporteur Member State, Austria, which was received by the EFSA on 7 February 2006 (Austria, 2006). The peer review was initiated on 1 September 2006 by dispatching the DAR to Member States and the applicant Lonza GmbH for consultation and comments. In addition, the EFSA conducted a public consultation on the DAR. The peer review process was subsequently terminated following the applicant s decision, in accordance with Article 11e, to withdraw support for the inclusion of metaldehyde in Annex I to Council Directive 91/414/EEC. Peer review conducted in accordance with Commission Regulation (EC) No 33/2008 Following the Commission Decision of 5 December 2008 (2008/934/EC) 10 concerning the noninclusion of metaldehyde in Annex I to Council Directive 91/414/EEC and the withdrawal of authorisations for plant protection products containing that substance, the applicant Lonza GmbH made a resubmission application for the inclusion of metaldehyde in Annex I in accordance with the provisions laid down in Chapter III of Commission Regulation (EC) No. 33/2008. The resubmission dossier included further data in response to the issues identified in the DAR. In accordance with Article 18, Austria, being the designated RMS, submitted an evaluation of the additional data in the format of an Additional Report. The Additional Report was received by the EFSA on 5 January 2010 (Austria, 2009). In accordance with Article 19, the EFSA distributed the Additional Report to Member States and the applicant for comments on 7 January In addition, the EFSA conducted a public consultation on the Additional Report. The EFSA collated and forwarded all comments received to the Commission on 22 February At the same time, the collated comments were forwarded to the RMS for compilation in the format of a Reporting Table. The applicant was invited to respond to the comments 7 OJ L224, , p.25 8 OJ L246, , p.19 9 OJ L 15, , p.5 10 OJ L 333, , p.11 4

5 in column 3 of the Reporting Table. The comments and the applicant s response were evaluated by the RMS in column 3. In accordance with Article 20, following consideration of the Additional Report, the comments received, and where necessary the DAR, the Commission decided to further consult the EFSA. By written request, received by the EFSA on 24 March 2010, the Commission requested the EFSA to arrange a consultation with Member State experts as appropriate and deliver its conclusions on metaldehyde within 6 months of the date of receipt of the request, subject to an extension of a maximum of 90 days where further information were required to be submitted by the applicant in accordance with Article 20(2). The scope of the peer review and the necessity for additional information, not concerning new studies, to be submitted by the applicant in accordance with Article 20(2), was considered in a telephone conference between the EFSA, the RMS, and the Commission on 7 April 2010; the applicant was also invited to give its view on the need for additional information. On the basis of the comments received, the applicant s response to the comments, and the RMS subsequent evaluation thereof, it was concluded that the EFSA should organise a consultation with Member State experts in the areas of mammalian toxicology and ecotoxicology, and that further information should be requested in the those sections. The outcome of the telephone conference, together with EFSA s further consideration of the comments is reflected in the conclusions set out in column 4 of the Reporting Table. All points that were identified as unresolved at the end of the comment evaluation phase and which required further consideration, including those issues to be considered in consultation with Member State experts, and the additional information to be submitted by the applicant, were compiled by the EFSA in the format of an Evaluation Table. The conclusions arising from the consideration by the EFSA, and as appropriate by the RMS, of the points identified in the Evaluation Table, together with the outcome of the expert discussions where these took place, were reported in the final column of the Evaluation Table. A final consultation on the conclusions arising from the peer review of the risk assessment took place with Member States via a written procedure in September This conclusion report summarises the outcome of the peer review of the risk assessment on the active substance and the representative formulation evaluated on the basis of the representative uses as a molluscicide on cereals (rye, oat, wheat, barley, and triticale) and oilseed rape, as proposed by the applicant. A list of the relevant end points for the active substance as well as the formulation is provided in Appendix A. In addition, a key supporting document to this conclusion is the Peer Review Report, which is a compilation of the documentation developed to evaluate and address all issues raised in the peer review, from the initial commenting phase to the conclusion. The Peer Review Report (EFSA, 2010) comprises the following documents: the comments received on the DAR and the Additional Report, the Reporting Tables (DAR and AR revision 1-1; 7 April 2010), the Evaluation Table (11 October 2010), the reports of the scientific consultation with Member State experts (where relevant). Given the importance of the DAR and the Additional Report including its addendum (compiled version of September 2010 containing all individually submitted addenda (Austria, 2010)) and the Peer Review Report, both documents are considered respectively as background documents A and B to this conclusion. 5

6 THE ACTIVE SUBSTANCE AND THE FORMULATED PRODUCT Metaldehyde is the common name for the chemical r-2,c-4,c-6,c-8-tetramethyl-1,3,5,7-tetroxocane or 2,4,6,8-tetramethyl-1,3,5,7-tetraoxacyclooctane (IUPAC). No ISO common name is required. The representative formulated product for the evaluation was Metarex, a ready to use bait (RB), which contains 50 g/kg metaldehyde. The representative uses evaluated are spreading (manually or with fertiliser spreader) on cereals (rye, oat, wheat, barley and triticale) and oilseed rape to control slugs and snails. Full details of the GAP can be found in the list of end points in Appendix A. CONCLUSIONS OF THE EVALUATION 1. Identity, physical/chemical/technical properties and methods of analysis The minimum purity of metaldehyde should not be less than 985 g/kg. Acetaldehyde was considered as a relevant impurity, with a maximum content of 1.5 g/kg in the manufactured active substance. There is currently no FAO specification for metaldehyde. The main data regarding the identity of metaldehyde and its physical and chemical properties are given in Appendix A. The assessment of the data package revealed no issues that need to be included as critical areas of concern with respect to the identity, physical, chemical and technical properties of metaldehyde or the respective formulation. Adequate analytical methods are available for the determination of metaldehyde in the technical material and in the representative formulation. Residues of metaldehyde in plants can be analysed by GC-MSD (enforcement method) or GC- MS/MS. In products of animal origin no analytical method for metaldehyde is necessary since there are no MRLs proposed. Soil and water are analysed for metaldehyde using also GC-MSD or GC- MS/MS and air by GC-MSD. An analytical method for body fluids and tissues is not required since metaldehyde is not classified as toxic or very toxic. 2. Mammalian toxicity Metaldehyde was discussed during the PRAPeR 79 mammalian toxicology experts meeting in July It can be considered that the batches used for the toxicological studies cover the proposed levels of impurities in the technical specification. The impurity acetaldehyde has to be considered toxicologically relevant but is not of concern at the proposed level. Harmful after a single oral dose in rats (Xn, R22 Harmful if swallowed), metaldehyde has a low acute toxicity after dermal exposure, is not irritant to the skin or eyes, and is not a skin sensitiser. After repeated administration, the target organs were the testes and the prostate in dogs, and the liver in rats and mice. Neurological signs were observed at acute toxic doses in rats, dogs and rabbit; and some deaths also occurred in dogs at 30 mg/kg bw/d, leading to the proposed classification of Xn, R48/22 Harmful: danger of serious damage to health by prolonged exposure if swallowed. The relevant shortterm NOAELs are 21 mg/kg bw/day for the rat (3-month study) and 10 mg/kg bw/day for the dog (1- year study, with also a NOAEL for acute neurological findings of 30 mg/kg bw/day). For the mouse, only a LOAEL of 19 mg/kg bw/day is identified in the 3-month range-finding study, based on histopathological findings in the liver at 54 mg/kg bw/day. Based on the available data, metaldehyde has no genotoxic or carcinogenic potential relevant to humans. The agreed long-term NOAELs are 2 mg/kg bw/day for the rat (2-year study) and 16 mg/kg bw/day for the mouse (78-week study). In the rat multigeneration study, metaldehyde did not affect the fertility or reproductive parameters. The parental NOAEL is 3.2 mg/kg bw/day, whereas the offspring NOAEL is 65 mg/kg bw/day and the reproductive NOAEL is 134 mg/kg bw/day. In the 6

7 developmental studies with rats and rabbits, no fetotoxicity or teratogenicity was observed in either species. In neurotoxicity studies with rats, the acute NOAEL is 75 mg/kg bw and the 90-day NOAEL for systemic toxicity and neurological findings (loss of hind limb function, attributed to spinal cord injury, not histopathologically investigated) is 39 mg/kg bw/day. The agreed Acceptable Daily Intake (ADI) is 0.02 mg/kg bw/day based on the 2-year rat study, the Acceptable Operator Exposure Level (AOEL) is 0.1 mg/kg bw/day based on the 52-week dog study, and the Acute Reference Dose (ARfD) is 0.3 mg/kg bw based on the acute neurological findings observed from the first week of the 52-week dog study. All reference values were derived with the use of a safety factor of 100. Considering the PHED model for granule application, including by default the use of gloves and protective clothing, the operator exposure estimates are below the AOEL for tractor-mounted equipment or hand-held equipment (belly grinder). Since the tractor-mounted equipment is broadcast application, lodging of granular bait in the foliage of oilseed rape cannot be excluded (see also section 3). The exposure of re-entry workers to these lodged granular baits has not been assessed, however it is unlikely that such an exposure would represent a concern. Due to the lack of data, the use of gloves might be considered. With regard to the bystander, the estimated systemic exposure is considered to be negligible. 3. Residues In the DAR (Austria, 2006) metabolism studies on sugar beet (root vegetables), strawberries (fruits), lettuce (leafy crops) and rice (cereals) have been evaluated. In the Additional Report metabolism studies on wheat and oilseed rape were provided to support the representative uses on cereals (rye, oat, wheat, barley and triticale) and oilseed rape in order to confirm the results of the metabolism studies already submitted. The metabolism data demonstrate that metaldehyde is extensively metabolised with natural incorporation of its carbon atoms. No significant metabolites were present. Therefore the residue definition is metaldehyde for both risk assessment and monitoring. Residues in rotational crops will not occur because the values for the degradation potential of metaldehyde in soil (DT 90 = days) and the DT 90 for the release of metaldehyde from the Metarex granular baits is days. Less than 10 % of the applied active substance remains in soil after 100 days based on the PEC (soil) values of mg/kg (day 0) and <0.001 mg/kg (day 100). Thus, no residues in edible portions of succeeding crops are expected, and confined rotational crop studies are therefore not considered necessary. The need for animal metabolism data is not triggered, however a lactating goat study was provided. The goat metabolism study revealed that radioactive residues of metaldehyde (administered even at exaggerated doses) are exhaled via CO 2 (58.9% and 58.1% of the total applied dose in the low dose and high dose animal, respectively) and that remaining radioactivity is broken down and incorporated into natural products such as fatty acids, amino acids and carbohydrates. The proposed GAP is for the EU; however, residue trials are only available for northern Europe. Therefore a data gap was identified for residue trials for southern Europe. Sixteen trials are available for wheat, residues were at the LOQ of either 0.01 mg/kg or 0.05 mg/kg. For oilseed rape there are eleven acceptable trials 7 x 0.01, 1 x 0.14, 2 x 0.06 and 1 x The positive results are from lodging of granular bait in the leaves, which in practice will be a rare occurrence for a crop like oilseed rape. The positive residues are in part a factor of the small plot size used in residue trials. Therefore in agricultural practice, with the bulk harvesting of oilseed rape, no significant residues will occur. There is also a large margin of safety to the ADI and ARfD. This cannot be considered the case for more open crops like lettuce where positive residues would be expected. In freezer storage stability studies metaldehyde was shown to be stable in wheat grain for 18 months and rape seed for 24 months. For the consumer risk assessment intakes were less than 1% of the ADI, and 0.2 % of the ARfD. 7

8 4. Environmental fate and behaviour In soil laboratory incubations under aerobic conditions in the dark, metaldehyde initially does not degrade, but after a lag phase of up to 19 days, it exhibited low persistence, forming no major (>10% applied radioactivity (AR)) metabolites 11. No metabolite accounted for >5% AR, a trigger pertinent for groundwater exposure assessment following European Commission (2003) guidance. Mineralisation of the carbon radiolabels (all carbons uniformly labelled) to carbon dioxide accounted for % AR after days (termination times of the incubations). The formation of unextractable residues (not extracted using methanol) for these radiolabels accounted for % AR after 60 days. In anaerobic soil incubations metaldehyde was essentially stable. Metaldehyde exhibited high to very high mobility in soil. There was no evidence of ph dependent adsorption. The representative product assessed, Metarex, is formulated as a granular bait. Satisfactory data on the kinetic release rate of metaldehyde from this specific product was provided and used to appropriately parameterise the FOCUS models and calculate the soil predicted environmental concentrations (PEC, as presented in Appendix A). It is important to note that these PECs in soil, surface water, sediment and groundwater are specific to the release rate characteristics of the formulated Metarex product only. Therefore, the PECs in this conclusion should not be extrapolated to other products, as these will exhibit different release kinetics. Data on release rates from each different formulated product will be required for the calculation of PECs specific for each product. In laboratory incubations in dark aerobic natural sediment water systems (four systems investigated), metaldehyde exhibited low to very high persistence. In the 2 systems where metaldehyde exhibited low persistence (where conditions were more oxidising, as indicated by the negative sediment redox potentials measured for the pertinent systems), the major metabolite acetaldehyde was formed (max. ca. 22 % AR in water and 5% in sediment). In these systems acetaldehyde exhibited moderate persistence. In the two less oxidising systems metaldehyde exhibited very high persistence and no major metabolites were formed. The unextractable sediment fraction (not extracted using methanol or dichloromethane) was a sink for the carbon radiolabels (all carbons uniformly labelled), accounting for % AR at study end ( days). Mineralisation of these radiolabels accounted for 5-8 % AR in the lower oxidation state systems and 62-69% AR under the more oxidising systems, at the end of the studies. The necessary surface water and sediment exposure assessments (PEC) were carried out for metaldehyde using the FOCUS (FOCUS, 2001) steps 1 to 3 12 approach with step 3 approaches being in accordance with EFSA, 2004b. PEC surface water and sediment were calculated for acetaldehyde by taking the maximum PEC calculated at step 3 for metaldehyde and factoring them for the maximum formation measured (% AR) in the sediment water studies. The necessary groundwater exposure assessments were appropriately carried out using FOCUS (FOCUS, 2000) scenarios and the models PEARL and PELMO for the active substance metaldehyde. The potential for groundwater exposure by metaldehyde, from the representative uses assessed on cereals and spring sown oilseed rape, above the parametric drinking water limit of 0.1 µg/l was concluded to be low in geoclimatic situations that are represented by all pertinent FOCUS groundwater scenarios (up to 9). For the representative use assessed on autumn sown (winter) oilseed rape the modelling results for 5 out of the 6 FOCUS groundwater scenarios indicated a low potential for groundwater exposure by metaldehyde above 0.1 µg/l. Under the geoclimatic conditions represented by the Piacenza scenario contamination of groundwater above 0.1 µg/l by metaldehyde cannot be excluded. The annual average groundwater recharge concentration in soil water leaving the 11 There are indications in the available data, that at higher exposure concentrations in soil (from ca. 6mg/kg and above) metaldehyde may be more persistent than indicated by the data cited here. An explanation for this might be an inhibition of microbially-mediated transformation processes. 12 At step 3, simulations correctly utilised the agreed Q10 of 2.58 (following EFSA, 2007) and Walker equation coefficient of 0.7. As the product is not sprayed, the parameterisation at step 3 also followed the EFSA (2004b) opinion. 13 Simulations complied with the EFSA (2004a) opinion and correctly utilised the agreed Q10 of 2.58 (following EFSA, 2007) and Walker equation coefficient of 0.7 8

9 top 1m soil column, calculated using the PELMO model, for the representative use on winter oilseed rape at the Piacenza scenario was µg metaldehyde/l. The PECs in soil, surface water, sediment, and groundwater covering the representative uses assessed for the specific granular bait product Metarex can be found in Appendix A. 5. Ecotoxicology Metaldehyde was discussed in the PRAPeR TC 38 ecotoxicology experts teleconference in July Birds may be exposed to metaldehyde by ingesting Metarex granular bait intentionally, by mistaking them for grit or seeds, or unintentionally during feeding in treated habitats. Exposure to the active substance may also result from the uptake of metaldehyde poisoned snails or slugs, feeding on contaminated earthworms, the ingestion of residues with plants or via drinking water from puddles in the field. The acute risk assessment for birds was based on a geomean from acute toxicity studies on Japanese quail (Coturnix japonica), mallard duck (Anas platyrhynchos) and pheasant (Phasianus colchicus). The geomean was accepted following the new guidance document (EFSA, 2009). Due to dosedependent food avoidance no reliable LC50 values could be obtained from the results of the dietary studies on Japanese quail and Peking duck (Anas platyrhynchos domestica). The short-term risk assessment was considered to be covered by the acute and long-term risk assessment. Based on the guidance document (European Commission, 2002) the acute and long-term risk to herbivorous birds was assessed as low. However, a high acute and long-term risk was identified for granivorous birds ingesting Metarex granular bait. The applicant provided a refined risk assessment including focal species, avoidance factor, PD and PT values, based on extensive field studies in Germany, France and Great Britain (bird scanning and carcass search in cereal and oilseed rape fields) and palatability studies (see below). The Member State experts considered the field study valid to identify focal bird species but they were not convinced that valid PT values could be derived from these studies (because foraging activity of the birds outside of the scanned area could not be detected, and no radio-tracking studies were available). In each of the two field studies in France (summer cereals and winter oilseed rape) a dead redstart (Phoenicurus phoenicurus) was found (residues of metaldehyde were detected in the carcass of both birds). Experts were concerned that carcass searches would only provide minimum numbers of incidents, and in particular smaller birds may have been overlooked during searches. Furthermore, concerns were raised that the carcass search areas were too small, given the low density of birds. From the field studies, the RMS identified the more relevant focal species based on occurrence and potential for high exposure (by multiplying PT, PD and FIR). The experts agreed with the principle of the approach and considered the PD data provided to be valid. Based on the revised calculation provided after the expert meeting (based on PD and FIR), the RMS had concerns that the revised list of focal species may not cover all Member States. In studies on the palatability of Metarex granular bait to house sparrow (Passer domesticus), grey partridge (Perdix perdix) and pheasant (6 hours no choice after grit and food deprivation, 3-4 days choice) there was no clear avoidance of the bait for any of the tested species. All birds however survived and did not show any symptoms of intoxication. The RMS was of the opinion that quite strong avoidance was demonstrated in the avoidance and dietary studies. Member State experts however considered that although avoidance studies did provide some reassurance that avoidance would occur, the available data were not robust enough to derive a value for avoidance. It was noted by the experts that some birds did eat bait in the avoidance study, and that their motivation to eat bait may be even higher under stressed environmental conditions. The majority of experts agreed not to use the AV factor. TER values were recalculated by the RMS after PRAPeR TC 38 for the revised focal species and without use of AV or PT values. TERs were clearly below the Annex VI trigger, indicating a high acute and long-term risk to granivorous birds for the representative uses. The risk 9

10 assessment was supported by calculation of the number of baits needed by the focal species to reach the acute LD50 and long-term NOEL, including an assessment factor. The focal species would need baits to reach LD50/10 and this number of baits would only cover % of their daily food intake rate. To reach the long-term NOEL/5 focal species would only need baits per day, equivalent to % of the daily food intake rate. The risk to birds from unintentional ingestion of bait as grit was considered to be covered by the risk assessment for granivorous birds. Slug-eating birds might ingest slugs that have fed on Metarex bait. Field data on metaldehyde residues in three different size classes of slugs were provided from two oilseed rape field sites in Germany treated with Metarex. The highest weighted mean concentration and the overall weighted mean for small and medium sized slugs was used for the acute and long-term risk assessment respectively. Decline rates in slugs were also calculated for the long-term risk assessment. Relevant focal bird species known to have slugs included in their diet 14 were identified from the extensive field studies mentioned above, and the birds most likely to be exposed were identified, based on FIR/bw since no sound species-specific PD values could be derived from literature, and Member State experts did not agree to the use of PT values (see above). A MAF was not considered relevant as slugs usually feed only once at a Metarex bait, which is only available immediately after the application. First tier TER calculations indicated a high acute and long-term risk to all slug-eating focal bird species. A refined risk assessment based on PT and PD was provided. PT refinements based on the field studies were not accepted for the same reason as mentioned above. Although a PD of 0.44 (based on literature data) was accepted as a conservative estimate for the proportion of slugs in the diet of birds in general, this was insufficient to address the long-term risk to slug-eating birds. The applicant provided a weight of evidence approach to address the risk to slug-eating birds. The field surveys did not indicate any mortality of slug-eating birds. Based on the study on residues in slugs, it was evident that metaldehyde concentration in slugs had substantially decreased within 1-2 weeks. The attractiveness of dead slugs to birds was questioned by the applicant, as literature studies with dead and desiccated insects indicated that birds had a preference for live and freshly dead insects. Furthermore, slugs dying after exposure to metaldehyde were found to have excessive slime formation, which would make them less attractive to birds. From literature data a maximum number of 19 slugs were found in the stomach of a single carrion crow (Corvus corone). The possible exposure from 19 slugs, based on the measured residue levels in slugs, was 47 times lower that the LD50 dose for a carrion crow. The number of slugs to reach LD50/10 for the focal slug-eating bird species was in the range of 2.9 to 179 slugs (correlated with weight of birds). The number of slugs would correspond to ingesting all affected slugs in 1m2 for a robin (Erithacus rubecula) to reach LD50. The rook (Corvus frugilegus) would need to ingest all affected slugs in 32m2. The number of slugs to reach the NOEL/5 was calculated to be in the range of 2.4 to 144 for the suit of relevant focal species. Member State experts were of the opinion that the evidence provided by the applicant was not sufficient to conclude on a low risk to birds from exposure to metaldehyde poisoned slugs. The concerns identified in relation to the use of the field studies to address the risk for granivorous birds also apply to the use of these same studies to address the risk to slug-eating birds (see above). Furthermore, Member State experts wondered if there may be exposure via other relevant feeding guilds for birds (e.g. arthropods exposed to metaldehyde) considering both the estimated high number of slugs needed to reach the LD50 for birds and the finding of 2 dead redstarts in the field. Consequently a data gap was identified for the applicant to provide a new risk assessment for birds that should consider acute and long-term risks. All relevant feeding guilds should be considered in order to explain the circumstances under which the death of birds observed in the field may have occurred. However, the RMS remained of the opinion that considering the large amount of field data 14 Literature data (see references in Additional Report) 10

11 available, and taking into account the current methodologies for higher tier risk assessments, new data would not significantly change the risk profile for metaldehyde. The risk to earthworm-eating birds was assessed as low, as was the risk to birds from the consumption of contaminated drinking water. In a first tier risk assessment for small herbivorous mammals the risk was assessed as low for all representative uses. However for granivorous mammals the acute and long-term TER values were significantly below the Annex VI trigger. Refinement of the risk assessment was based on two avoidance studies (bank vole and wood mouse; 4h food deprivation; no choice first day and choice between bait and seed during 3 days) and field effect studies on mammals by trapping and radiotracking in winter oilseed rape and winter cereal fields in Germany. Wood mouse (Apodemus sylvaticus) was considered a relevant focal species for all representative uses. Member State experts supported the selection of wood mouse as focal species and the use of a mean PD values derived from literature for the long-term risk assessment. However, the experts considered it inappropriate to refine the acute risk assessment based on PD or PT data. Moreover, the experts considered that mammals in the field might not have a choice between several food types (as in the avoidance test), in particular on large areas of bare soil where the appearance of food items was expected to be rare. For this reason an AV factor should not be used in the TER calculation. Member State experts had concerns regarding the PT values derived from the field studies. The type of radio-tracking was not considered adequate to obtain sound data on foraging activity (i.e. no continuous tracking, just fixes). Consequently the experts agreed not to use the PT, because no data on foraging activity inside and outside the crop are available. Field trapping studies indicated some mortality, but the data were considered to be inconclusive regarding population effects on mammals, and the studies were not representative for uses in South Europe. The Member State experts concluded that the evidence provided from the field studies was not sufficient to conclude that the risk to mammals would be low. The risk to slug-eating mammals was assessed as low, since such species were not considered likely to enter bare fields, e.g. shrews (Sorex spec.) and hedgehogs (Erinaceus europaeus). Furthermore, studies indicated that hedgehogs could consume 200 contaminated slugs (exact exposure level unknown) without showing adverse effects. Member State experts concluded that wood mouse was considered to be a more relevant focal species in the bare field, although it has never been reported that wood mice eat slugs. Therefore it is assumed that the risk via secondary poisoning was low. The risk to earthworm-eating mammals was assessed as low, as was the risk to mammals from the consumption of contaminated drinking water. Overall, based on the data available a high acute and long-term risk was assessed for granivorous mammals, and a data gap was identified for further data to be provided. Exposure from other feeding guilds should be considered, if there would be an indication from the risk assessment on birds that such feeding guilds may pose a risk. Metaldehyde was assessed as harmful to aquatic organisms (including gastropods) based on the data available. No toxicity studies on the formulation were provided as direct exposure to the aquatic environment was not expected. Based on FOCUSsw step 3 PEC values the risk to aquatic organisms was assessed as low for all scenarios for all representative uses. The risk from the metabolite acetaldehyde was additionally assessed as low. The potential for bioaccumulation was identified as low. The risk to bees, non-target arthropods, earthworms, non-target micro- and macro-organisms, biological methods of sewage treatment and non-target terrestrial plants was assessed as low for all representative uses. 11

12 6. Overview of the risk assessment of compounds listed in residue definitions triggering assessment of effects data for the environmental compartments 6.1. Soil Compound (name and/or code) Metaldehyde Persistence Following an initial lag phase of up to 19 days where degradation is negligible, the substance has low persistence biphasic with negligible initial decline DT to 22 days (20 C, pf2 soil moisture) Ecotoxicology The risk to soil-living organisms was assessed as low 6.2. Ground water Compound (name and/or code) Mobility in soil >0.1 μg/l 1m depth for the representative uses (at least one FOCUS scenario or relevant lysimeter) Pesticidal activity Toxicological relevance Ecotoxicological activity Metaldehyde high to very high mobility K Foc ml/g Yes at 1 out of 9 FOCUS scenarios at µg/L. Yes Yes Yes 6.3. Surface water and sediment Compound (name and/or code) Metaldehyde Acetaldehyde Ecotoxicology Metaldehyde is harmful to aquatic organisms. The risk from all representative uses was assessed as low. The risk from all representative uses was assessed as low. 12

13 6.4. Air Compound (name and/or code) Metaldehyde Toxicology No valid data available. No data required in view of the representative use and the physico-chemical properties. 13

14 LIST OF STUDIES TO BE GENERATED, STILL ONGOING OR AVAILABLE BUT NOT PEER REVIEWED Residue trials to support the representative uses in southern Europe (relevant for the all representative uses in southern Europe; submission date proposed by the applicant: unknown; see section 3). A new risk assessment for birds that should consider acute and long-term risks. All relevant feeding guilds should be considered in order to explain the circumstances under which the death of birds observed in the field may have occurred (relevant for all representative uses evaluated; submission date proposed by the applicant: none; see section 5). A new risk assessment for granivorous mammals that should consider acute and long-term risks. Exposure from other feeding guilds should be considered (e.g. omnivorous mammals), if there would be an indication from the risk assessment for birds that such guilds may pose a risk (relevant for all representative uses evaluated; submission date proposed by the applicant: none; see section 5). PARTICULAR CONDITIONS PROPOSED TO BE TAKEN INTO ACCOUNT TO MANAGE THE RISK(S) IDENTIFIED The use of PPE (gloves and coverall) is included by default in the operator exposure model used for the application of Metarex. The use of gloves might be considered for workers in view of possible exposure to bait lodged in the foliage of oilseed rape. ISSUES THAT COULD NOT BE FINALISED The consumer risk assessment cannot be finalised for the representative uses in southern Europe. CRITICAL AREAS OF CONCERN A high acute and long-term risk was identified for birds and mammals. 14

15 REFERENCES Austria, Draft Assessment Report (DAR) on the active substance metaldehyde prepared by the rapporteur Member State Austria in the framework of Directive 91/414/EEC, January Austria, Additional Report to the Draft Assessment Report on the active substance metaldehyde prepared by the rapporteur Member State Austria in the framework of Commission Regulation (EC) No 33/2008, December Austria, Final Addendum to the Additional Report on metaldehyde, compiled by EFSA, September EFSA (European Food Safety Authority), Peer Review Report to the conclusion regarding the peer review of the pesticide risk assessment of the active substance metaldehyde. Guidance documents 15 : European Commission, Guidance document on assessment of the relevance of metabolites in groundwater of substances regulated under council directive 91/414/EEC. SANCO/221/2000-rev 10-final, 25 February European Commission, Guidance Document on Risk Assessment for Birds and Mammals Under Council Directive 91/414/EEC. SANCO/4145/2000. EFSA (2007). Scientific Opinion of the Panel on Plant Protection Products and their Residues on a request from EFSA related to the default Q10 value used to describe the temperature effect on transformation rates of pesticides in soil. The EFSA Journal (2007) 622, EFSA (2004a). Opinion of the Scientific Panel on Plant Health, Plant Protection Products and their Residues on a request of EFSA related to FOCUS groundwater models comparability and the consistency of this risk assessment of groundwater contamination. The EFSA Journal (2004) 93, EFSA (2004b). Opinion of the Scientific Panel on Plant Health, Plant Protection Products and their Residues on a request from EFSA on the appropriateness of using the current FOCUS surface water for estimating exposure for risk assessment of aquatic ecotoxicology in the context of Council Directive 91/414/EEC. The EFSA Journal (2004) 145, EFSA (European Food Safety Authority), Guidance Document on Risk Assessment for Birds and Mammals on request of EFSA. EFSA Journal 2009; 7(12):1438. FOCUS (2001). FOCUS Surface Water Scenarios in the EU Evaluation Process under 91/414/EEC. Report of the FOCUS Working Group on Surface Water Scenarios, EC Document Reference SANCO/4802/2001-rev pp. FOCUS (2000). FOCUS Groundwater Scenarios in the EU review of active substances. Report of the FOCUS Groundwater Scenarios Workgroup, EC Document Reference SANCO/321/2000- rev pp, as updated by the Generic Guidance for FOCUS groundwater scenarios, version 1.1 dated April For further guidance documents see (EC) or (OECD) 15

16 APPENDICES APPENDIX A LIST OF END POINTS FOR THE ACTIVE SUBSTANCE AND THE REPRESENTATIVE FORMULATION List of Endpoints Identity, Physical and Chemical Properties, Details of Uses, Further Information Active substance (ISO Common Name) Function (e.g. fungicide) Metaldehyde (no ISO common name required) Molluscicide Rapporteur Member State Austria Co-rapporteur Member State -- Identity (Annex IIA, point 1) Chemical name (IUPAC) r-2,c-4,c-6,c-8-tetramethyl-1,3,5,7-tetroxocane 2,4,6,8-tetramethyl-1,3,5,7-tetraoxacyclooctane Chemical name (CA) 2,4,6,8-tetramethyl-1,3,5,7-tetraoxacyclooctane CIPAC No 62 CAS No (tetramer) (homopolymer) EC No (EINECS or ELINCS) FAO Specification (including year of publication) Minimum purity of the active substance as manufactured No specification is available at the moment of evaluation 985 g/kg Identity of relevant impurities (of toxicological, ecotoxicological and/or environmental concern) in the active substance as manufactured acetaldehyde max. 1.5 g/kg Molecular formula Molecular mass C 8 H 16 O 4 (tetramer) g/mol (tetramer) 16

17 Structural formula H 3 C O CH 3 O O H 3 C O CH 3 17

18 Physical and chemical properties (Annex IIA, point 2) Melting point (state purity) (99.5% (w/w)) metaldehyde starts to sublime at 191 C Boiling point (state purity) not applicable Temperature of decomposition (state purity) (99.5% (w/w)) metaldehyde starts to sublime at 191 C Appearance (state purity) Purified product (99.5% (w/w)) White crystalline powder Technical product (99.3% (w/w) White powder Vapour pressure (state temperature, state purity) 6.6 ± 0.3 Pa at 25 C (99.3% (w/w)) 4.4 ± 0.2 Pa at 20 C Henry s law constant 3.5 Pa.m³.mol -1 at 20 C values used for calculation: water solubility: g/l at 20 C vapour pressure: 4.4 Pa at 20 C Solubility in water (state temperature, state purity and ph) at C (99.3% (w/w)) g/l at ph 6.5 (unbuffered) at 20.0 ± 0.2 C (99.3% (w/w)) g/l at ph g/l at ph g/l at ph 9 Solubility in organic solvents (state temperature, state purity) Solubility all in g/l (99.5% (w/w)) at C hexane 52.1 x 10-3 methanol 1.73 toluene 0.53 tetrahydrofurane 1.56 at 20.0 ± 0.5 C ethyl acetoacetate at 20.0 C 1,2-dichloroethane 3.08 acetone

19 Surface tension (state concentration and temperature, state purity) Partition co-efficient (state temperature, ph and purity) at 19.5 ± 0.5 C (99.5% (w/w)) = 71.9 mn/m (0.204 g/l aqueous unbuffered solution) at C log P O/W = 0.12 at ph 6.7 (99.3% (w/w)) Effect of ph (4 to 10) not required, because metaldehyde is neither an acid nor a base Dissociation constant (state purity) UV/VIS absorption (max.) incl. (state purity, ph) metaldehyde does not dissociate in water c = 1.02 x 10-3 mol/l (0.18 g/l) (99.1% (w/w)) No significant absorption in neutral, acidic and alkaline medium occurs at any wavelength. Flammability (state purity) Highly flammable TGAI (99.5% (w/w)) Autoflammability No self ignition up to 400 C TGAI (99.5% (w/w)) Explosive properties (state purity) No explosive properties TGAI (99.5% (w/w)) St(H)2: strong dust explosion, indicator 2 Oxidising properties (state purity) No oxidizing properties Statement 19

20 Summary of representative uses evaluated (Metaldehyde)* Crop and/ or situation Membe r State or Countr y Produc t name F G or I Pests or Group of pests controlle d Preparation Application Application rate per treatment PHI (days ) Remarks: (a) (b ) (c) Type (d-f) Conc. of as (i) method kind (f-h) growth stage season (j) & numb er min/ max (k) interval between applicatio ns (min) kg as/hl (l) min max water L/ha min max kg as/ha (l) min max (m) Cereals (rye, oat, wheat, barley and triticale) EU Metare x F Slugs, Snails RB 50 g/kg Spreadi ng (manual ly or fertilise r spreade r) max 2 min 14 d not appli cable not appl icab le 0.35 n.a. [1] [2] Oilseed rape EU Metare x F Slugs, Snails RB 50 g/kg Spreadi ng (manual ly or max 2 min 14 d not appli cable not appl icab 0.35 n.a. [1] [2] 20

21 Crop and/ or situation Membe r State or Countr y Produc t name F G or I Pests or Group of pests controlle d Preparation Application Application rate per treatment PHI (days ) Remarks: (a) (b ) (c) Type (d-f) Conc. of as (i) method kind (f-h) growth stage season (j) & numb er min/ max (k) interval between applicatio ns (min) kg as/hl (l) min max water L/ha min max kg as/ha (l) min max (m) fertilise r spreade r) le [1] A high risk was identified for birds and mammals [2] The consumer risk assessment cannot be finalised for the representative uses in the South of Europe 21

22 Crop and/ or situation Membe r State or Countr y Produc t name F G or I Pests or Group of pests controlle d Preparation Application Application rate per treatment PHI (days ) Remarks: (a) (b ) (c) Type (d-f) Conc. of as (i) method kind (f-h) growth stage season (j) & numb er min/ max (k) interval between applicatio ns (min) kg as/hl (l) min max water L/ha min max kg as/ha (l) min max (m) (a) For crops, the EU and Codex classifications (both) should be taken into account; where relevant, the use situation should be described (e.g. fumigation of a structure) (b) Outdoor or field use (F), greenhouse application (G) or indoor application (I) (c) (d) (GR) e.g. biting and suckling insects, soil born insects, foliar fungi, weeds e.g. wettable powder (WP), emulsifiable concentrate (EC), granule (e) GCPF Codes - GIFAP Technical Monograph No 2, 1989 (f) All abbreviations used must be explained (i) g/kg or g/l. Normally the rate should be given for the active substance (according to ISO) and not for the variant in order to compare the rate for same active substances used in different variants (e.g. fluoroxypyr). certain cases, where only one variant is synthesised, it is more appropriate to give the rate for the variant (e.g. benthiavalicarb-isopropyl). (j) Growth stage at last treatment (BBCH Monograph, Growth Stages of Plants, 1997, Blackwell, ISBN ), including where relevant, information on season at time of application (k) Indicate the minimum and maximum number of application possible under practical conditions of use (l) The values should be given in g or kg whatever gives the more manageable number (e.g. 200 kg/ha instead of g/ha or 12.5 g/ha 22