Conclusion on the peer review of the pesticide risk assessment of the active substance bifenthrin

Bifenthrin is one of the 79 substances of the third stage Part A of the review programme covered by Commission Regulation (EC) No 1490/20023 as amended by Commission Regulation (EC) No 1095/20074. This Regulation requires the European Food Safety Authority (EFSA) to organise upon request of the European Commission a peer review of the initial evaluation, i.e. the Draft Assessment Report (DAR), provided by the designated rapporteur Member State and to provide within six months a conclusion on the risk assessment to the European Commission. France being the designated rapporteur Member State submitted the DAR on bifenthrin in accordance with the provisions of Article 10(1) of the Regulation (EC) No 1490/2002, which was received by the EFSA on 15 December 2005. The peer review was initiated on 1 June 2006 by dispatching the DAR for consultation of the Member States and on 12 May 2006 to the sole applicant FMC Chemicals. Subsequently, the comments received on the DAR were examined and responded by the rapporteur Member State in the reporting table. This table was evaluated by EFSA to identify the remaining issues which were agreed during a written procedure in February 2008. The identified issues as well as further information made available by the applicant upon request were evaluated in a series of scientific meetings with Member State experts in June -July 2008. A final discussion of the outcome of the consultation of experts took place during a written procedure with the Member States in September 2008 leading to the conclusions set out in the EFSA Conclusion finalised on 30 September 2008 (EFSA Scientific Report (2008) 186). Following the Commission Decision of 30 November 2009 (2009/887/EC) 5 concerning the noninclusion of bifenthrin in Annex I to Council Directive 91/414/EEC and the withdrawal of authorisations for plant protection products containing that substance, the applicant FMC Chemicals made a resubmission application for the inclusion of bifenthrin in Annex I in accordance with the provisions laid down in Chapter III of Commission Regulation (EC) No. 33/20086. The resubmission dossier included further data in response to the issues identified in the conclusions leading to the Decision on non-inclusion, as set out in the Review Report (SANCO/125/08) as follows: The fate and behaviour in soil and water, due to the possible presence of major soil metabolites, the relevance of which must be determined and, if necessary, further assessed. As a consequence, the risk to groundwater, could not be finalised; The risk to aquatic organisms which, with the exception of invertebrates and algae, does not generate an acceptable use; The risk to several species of mammals, non-target arthropods, non-target plants and nontarget soil macro-organisms. and concerns were identified with regard to: The risk to consumers, which may be underestimated, given the data gaps identified in the residue section, and the possible impact of the different isomers constituting bifenthrin; The potential for contamination of groundwater by the major soil metabolite TFP acid;. The unacceptable high risk to aquatic vertebrates; The long term risk to mammals; The risk from secondary poisoning of earthworm-eating mammals; The risk from bioaccumulation through the aquatic food chain which is not finalised; The risk to non-target arthropods (in-field), non-target plants and non-target soil macroorganisms which remains inconclusive. In accordance with Article 18 of Commission Regulation (EC) No. 33/2008, France, 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 6 August 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 10 August 2010. The EFSA collated and forwarded all comments received to the European Commission on 23 September 2010. In accordance with Article 20, following consideration of the Additional Report and the comments received, the European Commission requested the EFSA to deliver its conclusions on bifenthrin. The conclusion of the original review was reached on the basis of the evaluation of the representative uses as an insecticide, which comprise of foliar spraying in cereals, grape and pome fruit for the control of a broad range of foliar pests, sucking and biting insects, mites, aphids. Full details of the GAP can be found in Appendix A. The conclusions laid down in this report were reached on the basis of the evaluation of the representative uses of bifenthrin as an insecticide on cereals, ornamentals and head cabbage, as proposed by the applicant. Full details of the representative uses can be found in Appendix A to this report. The representative formulated product for the evaluation was 'Talstar 8 SC', a suspension concentrate (SC) containing 80 g/l bifenthrin. Sufficient analytical methods as well as methods and data relating to physical, chemical and technical properties are available to ensure that quality control measurements of the plant protection product are possible. Adequate methods are available to monitor bifenthrin residues in food/feed of plant and animal origin, in the environmental matrices and in body fluids and tissues. As for mammalian toxicity, bifenthrin is Toxic if swallowed (R25), it is toxic by inhalation (R23 Toxic by inhalation proposed). Bifenthrin is a skin sensitiser (R43 May cause skin sensitisation by skin contact proposed). It is not a skin or eye irritant. The main effect observed for repeated exposures is tremor and/or neurotoxic effects. The relevant short-term toxicity NOAEL is 2.5 mg/kg bw/day in dogs whereas for long-term exposures the NOAELs is 4.7 mg/kg bw/day in rats. Bifenthrin did not show any genotoxic potential. Due to the occurrence of bladder leiomyosarcomas/hemangiopericytomas in mice and as their relevance to humans could not be excluded, and the historical control data were not conclusive, R40 (Carc. Cat. 3) was proposed. In multigeneration studies the relevant maternal NOAEL is 3.0 mg/kg bw/day and the reproductive NOAEL is 5 mg/kg bw/day, based on the occurrence of tremors and marginally lower body weight in the P and F1 generation females during gestation and lactation. Bifenthrin did not show any teratogenic potential (maternal NOAEL> 7.4 mg/kg bw/day and developmental NOAEL >2 mg/kg bw/day). Bifenthrin did not show developmental neurotoxicity potential. The ADI is 0.015 mg/kg bw/day based on the 1-year dog study with a SF of 100, supported by the developmental study in rats. The ARfD is 0.03 mg/kg bw based on the 90-day neurotoxicity study with a SF of 100. The AOEL is 0.0075 mg/kg bw/day (SF 100 and correction factor of 50% for limited oral absorption). The operator, worker and bystander exposure showed levels below the AOEL. In the metabolism studies on apples (fruit crops), cotton seed (pulses and oilseeds) and maize plants (cereals) bifenthrin was found to be the predominant compound of the total residues. No significant cis-trans isomerisation and translocation of residues through the plant were observed. The proposed global residue definition for monitoring and risk assessment in plant commodities is bifenthrin (sum of isomers). Complete residue database were provided to support the representative uses on cereals (wheat, triticale, rye, barley and oat) for both Northern and Southern Europe and to propose MRLs while 4 additional residue trials are required on head cabbage (Northern Europe). The nature of the residues in processed commodities was sufficiently addressed for pasteurisation and baking, brewing and boiling but not for sterilisation. A data gap was identified to require a new hydrolysis study simulating the conditions of sterilisation to determine the nature of the residues in processed commodities. Based on the metabolism studies in ruminants and poultry, the proposed residue definition for monitoring for animal commodities is bifenthrin (sum of isomers). For risk assessment, the residue definition proposals are as follows: -ruminant liver and kidney: sum of bifenthrin (sum of isomers) and BP-acid, expressed as bifenthrin (conversion factor of 2 for monitoring to risk assessment); -eggs, poultry liver: sum of bifenthrin (sum of isomers) and hydroxyl-methyl bifenthrin and its fatty acid conjugates, expressed as bifenthrin (conversion factor of 2 for monitoring to risk assessment); -for milk and all other animal products: bifenthrin (sum of isomers). The storage time interval of the samples from the residue trials on cereals and head cabbage and of the animal tissues from the feeding studies can be considered as covered by the available storage stability data. Under normal agricultural practices, bifenthrin residue levels in the edible parts of the rotational crops intended for human consumption and as feed items are expected to be below 0.01 and 0.05 mg/kg, respectively. No chronic and acute intake concerns were identified according to EFSA PRIMo rev. 2A model. The consumer risk assessment should be regarded as provisional pending the submission of the additional residue trials on head cabbage. The potential for a different degradation of bifenthrin enantiomers in plant and animal commodities was considered as sufficiently addressed since the S/R enantiomeric ratio of the parent bifenthrin was shown to remain unchanged (S/R ratio: 1/1) both in cereals and head cabbage samples from the residue trials and in fat samples from the rat. Based on the available residue datasets an MRL of 0.05 mg/kg is proposed for wheat, triticale and rye grain and a MRL of 0.1 mg/kg is set for barley and oat grain. A provisional MRL of 0.3 mg/kg is proposed for head cabbage. MRLs were also defined for animal matrices. In soil under aerobic conditions bifenthrin exhibits moderate to high persistence forming the major soil metabolite TFP acid (accounting for up to 11.6% of applied radioactivity (AR)) which exhibits low to moderate persistence and the minor non-transient metabolite 4'-OH bifenthrin (accounting for up to 8.3% AR) which exhibits moderate persistence. Mineralisation of both the cyclopropyl and phenyl rings to carbon dioxide accounted for 30-39% AR after 90 days. The formation of unextractable residues was a sink that accounted for 14-18 % AR after 90 days. Bifenthrin is immobile in soil, 4'-OH bifenthrin is expected to be immobile in soil though there was a data gap identified to confirm this. Metabolite TFP acid exhibited very high to medium mobility. There was no indication that adsorption of either bifenthrin or 4'-OH bifenthrin was pH dependent, whereas TFP acid exhibited pH dependent adsorption. In dark natural sediment water systems bifenthrin degraded exhibiting high persistence in sediment to the metabolite 4'-OH bifenthrin in sediment (max. 11.1% AR). The terminal metabolite, CO2, was a sink in the material balance from both the cyclopropyl and phenyl radiolabels accounting for a maximum of 3-27 % AR at 99 days (study end). Unextracted sediment residues accounted for 6-14 % AR at study end. The necessary surface water and sediment exposure assessments were appropriately carried out using the agreed FOCUS scenarios approach for bifenthrin at steps 1-4, with spray drift and run-off mitigation being applied at step 4 for the applied for representative uses on cereals and head cabbage. For the metabolite TFP acid and additionally for the 4'-OH bifenthrin, appropriate FOCUS step 2 calculations were carried out. These values are the basis for the risk assessment discussed in this conclusion. Regarding the outdoor uses on ornamentals, a data gap was identified for exposure estimations for surface water and sediment. The potential for groundwater exposure from the representative uses on cereals and head cabbage by bifenthrin, TFP acid and 4'-OH bifenthrin above the parametric drinking water limit of 0.1 mu g/L, was concluded to be low in geoclimatic situations that are represented by the relevant FOCUS groundwater scenarios. The potential for groundwater exposure from the uses on ornamentals was accepted to be covered by the estimations available for cereals. Since bifenthrin and its two metabolites relevant for the environment consist of 2 enantiomers and because only limited information on the behaviour of the enantiomers of bifenthrin in the environment was available, a data gap regarding this issue remained. Low acute, short-term and long-term risks were indicated with the first-tier risk assessment for birds and a low acute risk was indicated for mammals for the outdoor representative uses. A potential high long-term risk to mammals was identified with the first tier for outdoor representative uses; however, the risk was assessed as low with a subsequent assessment based on the Guidance Document on Birds and Mammals (EFSA, 2009). The risk of bifenthrin to earthworm-eating birds and mammals was assessed as low for the outdoor representative uses, based on PECsoil plateau of 0.027 mg/kg. The risk to fish-eating birds and mammals was considered to be low based on the BCF value for fish of 1709. Since bifenthrin has a potential for biomagnification i.e. potential for accumulation observed in a metabolism study on rat and estimated biomagnification factor (BAF)>1, a food chain modelling has been carried out. However, the experts at the PRAPeR 87 experts' meeting identified several uncertainties in the model assumptions and parameterization and therefore they concluded that a high risk from biomagnification in the terrestrial food chain cannot be excluded. Therefore the experts agreed to identify a data gap for the applicant to further address this risk. The risk to birds and mammals for the indoor representative use in ornamentals is low since no exposure is expected. The first tier risk assessment indicated a potential high acute and long-term risk to fish and aquatic invertebrates. The estimated TER values, based on the FOCUS PECsw step 4 (20-25 m no-spray buffer zones and run-off reduction) and higher tier toxicity end points, were above the Annex VI trigger values indicating a low risk. To fulfil the data gap identified during the PRAPeR 53 to further address the risk from bioaccumulation through the food chain, a biomagnification modelling has been carried out and provided in the Additional Report. This modelling has been discussed at the PRAPeR 87. The experts agreed that a high risk from bioaccumulation through the food chain for aquatic organisms could not be excluded on the basis of the available data. Therefore, a data gap was identified to further address the risk from biomagnification in the aquatic food chain and to address the uncertainties raised. The experts concluded that a high risk was identified for bifenthrin to bees for all the outdoor representative uses. Risk mitigation measures should be applied to avoid the exposure of bees and effects from residual toxicity (by considering an appropriate interval between the last application and flowering). It could be concluded from the available information that there is a high risk to non-target arthropods for in-field and off-field areas within the treated area from the outdoor representative uses. Risk mitigation measures are required to reduce the exposure of non-target arthropods in the off-field areas. A data gap was identified for the applicant to provide further data to address the residual toxicity of bifenthrin to non-target arthropods and the potential for recovery/recolonisation. The acute and long-term risk of bifenthrin and TFP acid to earthworms was assessed as low. The risk to soil macro-organisms, micro-organisms, non-target plants and biological methods of sewage treatment was assessed as low for all the representative uses evaluated.