Review of the existing maximum residue levels for spirotetramat according to Article 12 of Regulation (EC) No 396/2005
2020; Wiley; Volume: 18; Issue: 1 Linguagem: Inglês
10.2903/j.efsa.2020.5960
ISSN1831-4732
AutoresMaria Anastassiadou, Giovanni Bernasconi, Alba Brancato, Luis Carrasco Cabrera, Luna Greco, Samira Jarrah, Aija Kazocina, Renata Leuschner, José Oriol Magrans, Ileana Miron, Stéfanie Nave, Ragnor Pedersen, Hermine Reich, Alejandro Rojas, Angela Sacchi, Miguel Santos, Alois Stanek, Anne Theobald, Bénédicte Vagenende, Alessia Verani,
Tópico(s)Pharmaceutical Economics and Policy
ResumoEFSA JournalVolume 18, Issue 1 e05960 Reasoned OpinionOpen Access Review of the existing maximum residue levels for spirotetramat according to Article 12 of Regulation (EC) No 396/2005 European Food Safety Authority (EFSA), Corresponding Author European Food Safety Authority (EFSA) pesticides.mrl@efsa.europa.eu Correspondence: pesticides.mrl@efsa.europa.euSearch for more papers by this authorMaria Anastassiadou, Maria AnastassiadouSearch for more papers by this authorGiovanni Bernasconi, Giovanni BernasconiSearch for more papers by this authorAlba Brancato, Alba BrancatoSearch for more papers by this authorLuis Carrasco Cabrera, Luis Carrasco CabreraSearch for more papers by this authorLuna Greco, Luna GrecoSearch for more papers by this authorSamira Jarrah, Samira JarrahSearch for more papers by this authorAija Kazocina, Aija KazocinaSearch for more papers by this authorRenata Leuschner, Renata LeuschnerSearch for more papers by this authorJose Oriol Magrans, Jose Oriol MagransSearch for more papers by this authorIleana Miron, Ileana MironSearch for more papers by this authorStefanie Nave, Stefanie NaveSearch for more papers by this authorRagnor Pedersen, Ragnor PedersenSearch for more papers by this authorHermine Reich, Hermine ReichSearch for more papers by this authorAlejandro Rojas, Alejandro RojasSearch for more papers by this authorAngela Sacchi, Angela SacchiSearch for more papers by this authorMiguel Santos, Miguel SantosSearch for more papers by this authorAlois Stanek, Alois StanekSearch for more papers by this authorAnne Theobald, Anne TheobaldSearch for more papers by this authorBenedicte Vagenende, Benedicte VagenendeSearch for more papers by this authorAlessia Verani, Alessia VeraniSearch for more papers by this author European Food Safety Authority (EFSA), Corresponding Author European Food Safety Authority (EFSA) pesticides.mrl@efsa.europa.eu Correspondence: pesticides.mrl@efsa.europa.euSearch for more papers by this authorMaria Anastassiadou, Maria AnastassiadouSearch for more papers by this authorGiovanni Bernasconi, Giovanni BernasconiSearch for more papers by this authorAlba Brancato, Alba BrancatoSearch for more papers by this authorLuis Carrasco Cabrera, Luis Carrasco CabreraSearch for more papers by this authorLuna Greco, Luna GrecoSearch for more papers by this authorSamira Jarrah, Samira JarrahSearch for more papers by this authorAija Kazocina, Aija KazocinaSearch for more papers by this authorRenata Leuschner, Renata LeuschnerSearch for more papers by this authorJose Oriol Magrans, Jose Oriol MagransSearch for more papers by this authorIleana Miron, Ileana MironSearch for more papers by this authorStefanie Nave, Stefanie NaveSearch for more papers by this authorRagnor Pedersen, Ragnor PedersenSearch for more papers by this authorHermine Reich, Hermine ReichSearch for more papers by this authorAlejandro Rojas, Alejandro RojasSearch for more papers by this authorAngela Sacchi, Angela SacchiSearch for more papers by this authorMiguel Santos, Miguel SantosSearch for more papers by this authorAlois Stanek, Alois StanekSearch for more papers by this authorAnne Theobald, Anne TheobaldSearch for more papers by this authorBenedicte Vagenende, Benedicte VagenendeSearch for more papers by this authorAlessia Verani, Alessia VeraniSearch for more papers by this author First published: 23 January 2020 https://doi.org/10.2903/j.efsa.2020.5960Citations: 2 Requestor: European Commission Question number: EFSA-Q-2013-00911 Acknowledgement: EFSA wishes to thank the rapporteur Member State Austria for the preparatory work and Silvia Ruocco, Laszlo Bura, Georgios Chatzisotiriou, and Viktor Toth for the support provided to this scientific output. Approved: 3 December 2019 AboutSectionsPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract According to Article 12 of Regulation (EC) No 396/2005, EFSA has reviewed the maximum residue levels (MRLs) currently established at European level for the pesticide active substance spirotetramat. To assess the occurrence of spirotetramat residues in plants, processed commodities, rotational crops and livestock, EFSA considered the conclusions derived in the framework of Directive 91/414/EEC, Regulation (EC) No 1107/2009 and Commission Regulation (EU) No 188/2011, the MRLs established by the Codex Alimentarius Commission as well as the import tolerances and European authorisations reported by Member States (including the supporting residue data). Based on the assessment of the available data, MRL proposals were derived and a consumer risk assessment was carried out. Although no apparent risk to consumers was identified, some information required by the regulatory framework was missing. Hence, the consumer risk assessment is considered indicative only and some MRL proposals derived by EFSA still require further consideration by risk managers. Summary Spirotetramat was approved on 1 May 2014 by means of Commission Regulation No 1177/2013 of 20 November 2013, in the framework of Regulation (EC) No 1107/2009. As the active substance was approved after the entry into force of Regulation (EC) No 396/2005 on 2 September 2008, the European Food Safety Authority (EFSA) is required to provide a reasoned opinion on the review of the existing maximum residue levels (MRLs) for that active substance in compliance with Article 12(1) of the aforementioned regulation. As the basis for the MRL review, on 12 July 2018 EFSA initiated the collection of data for this active substance. In a first step, Member States were invited to submit by 10 August 2018 their national Good Agricultural Practices (GAPs) in a standardised way, in the format of specific GAP forms, allowing the designated rapporteur Member State (RMS) Austria (AT) to identify the critical GAPs in the format of a specific GAP overview file. Subsequently, Member States were requested to provide residue data supporting the critical GAPs, within a period of 1 month, by 15 November 2018. On the basis of all the data submitted by Member States and by the EU Reference Laboratories for Pesticides Residues (EURL), EFSA asked the RMS to complete the Pesticide Residues Overview File (PROFile) and to prepare a supporting evaluation report. The PROFile and evaluation report, together with an updated GAP overview file were provided by the RMS to EFSA on 5 March 2019. Subsequently, EFSA performed the completeness check of these documents with the RMS. The outcome of this exercise including the clarifications provided by the RMS, if any, was compiled in the completeness check report. Based on the information provided by the RMS, Member States and the EURL, and taking into account the conclusions derived by EFSA in the framework of Commission Regulation (EU) No 188/2011 and the MRLs established by the Codex Alimentarius Commission, EFSA prepared in October 2019 a draft reasoned opinion, which was circulated to Member States for consultation via a written procedure. Comments received by 16 November 2019 were considered during the finalisation of this reasoned opinion. The following conclusions are derived. The metabolism of spirotetramat in plant was investigated in primary and rotational crops. According to the results of the metabolism studies, the residue definition can be proposed as sum of spirotetramat and spirotetramat-enol, expressed as spirotetramat for enforcement and as sum of spirotetramat, spirotetramat-enol, spirotetramat-enol-glucoside(Glc), spirotetramat-ketohydroxy and spirotetramat-monohydroxy, expressed as spirotetramat for risk assessment. These residue definitions are also applicable to processed commodities and rotational crops. Fully validated analytical methods are available for the enforcement of the proposed residue definition in high water, high acid, high oil and dry commodities at the combined limit of quantification (LOQ) of 0.02 mg/kg and in difficult matrices (hops) at the combined LOQ of 0.2 mg/kg. According to the EURLs, the LOQ of 0.02 mg/kg is achievable in the four main matrices by using the QuEChERS method in routine analyses. Available residue trials data were considered sufficient to derive MRL proposals as well as risk assessment values for all commodities under evaluation, except for apricots, sweet corn, Brussels sprouts, head cabbage, kale, Chinese cabbage and kohlrabi, where tentative MRLs are derived. For leeks, kumquats, peas without pods, dry lentils and herbal infusion from flowers, an MRL proposal could not be derived due to insufficient residue trials. Spirotetramat is authorised for use on crops that might be fed to livestock. Livestock dietary burden calculations were therefore performed for different groups of livestock according to OECD guidance. The dietary burdens calculated for all groups of livestock were found to exceed the trigger value of 0.1 mg/kg dry matter (DM). Behaviour of residues was therefore assessed in all commodities of animal origin. The metabolism of spirotetramat residues in livestock was investigated in lactating goats and laying hens at dose rate covering the maximum dietary burdens calculated in this review. According to the results of these studies, the residue definitions in livestock commodities for enforcement was proposed as spirotetramat-enol only, expressed as spirotetramat and risk assessment as spirotetramat-enol and spirotetramat-enol-GA expressed as spirotetramat. An analytical method for the enforcement of the proposed residue definition at the LOQ of 0.005 mg/kg in milk and 0.01 mg/kg in fat, liver, kidney, muscle, and egg, is available. According to the EURLs screening detection limits (SDLs) of 0.005 mg/kg in egg, 0.01 mg/kg in milk and 0.02 mg/kg in muscle is achievable by using the QuEChERS method in routine analyses. A livestock feeding study on dairy cows and the metabolism study on laying hens were used to derive MRL and risk assessment values in milk, eggs, and tissues of ruminants and poultry. Since extrapolation from ruminants to pigs is acceptable, results of the livestock feeding study on ruminants were relied upon to derive the MRL and risk assessment values for swine. Chronic and acute consumer exposure resulting from the authorised uses reported in the framework of this review was calculated using revision 3 of the EFSA PRIMo. For those commodities where data were insufficient to derive a MRL, EFSA considered the existing EU MRL for an indicative calculation. The highest chronic exposure represented 20% of the acceptable daily intake (ADI) (NL toddler) and the highest acute exposure amounted to 17% of the acute reference dose (ARfD) (peaches). Apart from the MRLs evaluated in the framework of this review, internationally recommended CXLs have also been established for spirotetramat. Additional calculations of the consumer exposure, considering these CXLs, were therefore carried out. The highest chronic exposure represented 25% of the ADI (NL toddler) and the highest acute exposure amounted to 29% of the ARfD (kales). EFSA emphasises that the above assessment does not consider the possible impact of plant and livestock metabolism on the isomer ratio of spirotetramat and further investigation on this matter would in principle be required. EFSA notes that in view of the large margin of safety in the exposure calculations, the potential change of isomer ratios in the final residues is not expected to be of concern for the authorised use reported in the framework of this review. In case future uses of active substance would lead to a higher consumer exposure, further information regarding the impact of plant and/or livestock metabolism on the isomer ratio might be required. Background Regulation (EC) No 396/20051 (hereinafter referred to as 'the Regulation') establishes the rules governing the setting and the review of pesticide maximum residue levels (MRLs) at European level. Article 12(1) of that Regulation stipulates that the European Food Safety Authority (EFSA) shall provide within 12 months from the date of the inclusion or non-inclusion of an active substance in Annex I to Directive 91/414/EEC2 a reasoned opinion on the review of the existing MRLs for that active substance. Spirotetramat was included in Annex I to Council Directive 91/414/EEC on 01 May 2014 by means of Commission Regulation No 1177/20133 which has been deemed to be approved under Regulation (EC) No 1107/20094, in accordance with Commission Implementing Regulation (EU) No 540/20115, as amended by Commission Implementing Regulation (EU) No 541/20116. Therefore, EFSA initiated the review of all existing MRLs for that active substance. By way of background information, in the framework of Commission Regulation (EU) No 188/20117, spirotetramat was evaluated by Austria, designated as rapporteur Member State (RMS). Subsequently, a peer review on the initial evaluation of the RMS was conducted by EFSA, leading to the conclusions as set out in the EFSA scientific output (EFSA, 2013a). According to the legal provisions, EFSA shall base its reasoned opinion in particular on the relevant assessment report prepared under Directive 91/414/EEC repealed by Regulation (EC) No 1107/2009. It should be noted, however, that, in the framework of Regulation (EC) No 1107/2009, only a few representative uses are evaluated (citrus, lettuce), whereas MRLs set out in Regulation (EC) No 396/2005 should accommodate all uses authorised within the European Union (EU), and uses authorised in third countries that have a significant impact on international trade. The information included in the assessment report prepared under Regulation (EC) No 1107/2009 is therefore insufficient for the assessment of all existing MRLs for a given active substance. To gain an overview of the pesticide residues data that have been considered for the setting of the existing MRLs, EFSA developed the Pesticide Residues Overview File (PROFile). The PROFile is an inventory of all pesticide residues data relevant to the risk assessment and MRL setting for a given active substance. This includes data on: the nature and magnitude of residues in primary crops; the nature and magnitude of residues in processed commodities; the nature and magnitude of residues in rotational crops; the nature and magnitude of residues in livestock commodities; the analytical methods for enforcement of the proposed MRLs. As the basis for the MRL review, on 12 July 2018, EFSA initiated the collection of data for this active substance. In a first step, Member States were invited to submit by 10 August 2018 their Good Agricultural Practices (GAPs) that are authorised nationally, in a standardised way, in the format of specific GAP forms. In the framework of this consultation, 21 Member States provided feedback on their national authorisations of spirotetramat. Based on the GAP data submitted, the designated RMS Austria was asked to identify the critical GAPs to be further considered in the assessment, in the format of (a) specific GAP overview file(s). Subsequently, in a second step, Member States were requested to provide residue data supporting the critical GAPs by 15 November 2018. On the basis of all the data submitted by Member States and the EU Reference Laboratories for Pesticides Residues (EURL), EFSA asked Austria to complete the PROFile and to prepare a supporting evaluation report. The PROFile and the supporting evaluation report, together with an updated GAP overview file were provided by the RMS to EFSA on 5 March 2019. Subsequently, EFSA performed the completeness check of these documents with the RMS. The outcome of this exercise including the clarifications provided by the RMS, if any, was compiled in the completeness check report. Considering all the available information, and taking into account the MRLs established by the Codex Alimentarius Commission (CAC) (i.e. codex maximum residue limits (CXLs)), EFSA prepared in September-October 2019 a draft reasoned opinion, which was circulated to Member States for commenting via a written procedure. All comments received by 16 November 2019 were considered by EFSA during the finalisation of the reasoned opinion. The evaluation report submitted by the RMS (Austria, 2019), taking into account also the information provided by Member States during the collection of data, and the EURL report on analytical methods (EURL, 2018) are considered as main supporting documents to this reasoned opinion and, thus, made publicly available. In addition, further supporting documents to this reasoned opinion are the completeness check report (EFSA, 2019c) and the Member States consultation report (EFSA, 2019d). These reports are developed to address all issues raised in the course of the review, from the initial completeness check to the reasoned opinion. Furthermore, the exposure calculations for all crops reported in the framework of this review performed using the EFSA Pesticide Residues Intake Model (PRIMo) and the PROFile as well as the GAP overview file listing all authorised uses and import tolerances are key supporting documents and made publicly available as background documents to this reasoned opinion. A screenshot of the report sheet of the PRIMo is presented in Appendix C. Terms of Reference According to Article 12 of Regulation (EC) No 396/2005, EFSA shall provide a reasoned opinion on: the inclusion of the active substance in Annex IV to the Regulation, when appropriate; the necessity of setting new MRLs for the active substance or deleting/modifying existing MRLs set out in Annex II or III of the Regulation; the inclusion of the recommended MRLs in Annex II or III to the Regulation; the setting of specific processing factors as referred to in Article 20(2) of the Regulation. The active substance and its use pattern Spirotetramat is the ISO common name for ethyl cis-8-methoxy-2-oxo-3-(2,5-xylyl)-1-azaspiro[4.5]dec-3-en-4-yl carbonate (IUPAC). The chemical structure of the active substance and its main metabolite are reported in Appendix F. The EU MRLs for spirotetramat are established in Annexes IIIA of Regulation (EC) No 396/2005. CXLs for spirotetramat were also established by the CAC. An overview of the MRL changes that occurred since the entry into force of the Regulation mentioned above is provided below (Table 1). Table 1. Overview of the MRL changes since the entry into force of Regulation (EC) No 396/2005 Procedure Legal implementation Remarks MRL application Not yet voted and legally implemented Reasoned opinion on the modification of the existing maximum residue levels for spirotetramat in small fruits and berries (EFSA, 2019b). This RO was not considered in this assessment MRL application Regulation (EC) No 2019/1015 Reasoned opinion on the modification of the existing maximum residue levels for spirotetramat in various crops (EFSA, 2019a) MRL application Regulation (EC) No 2017/1016 Reasoned opinion on the setting of maximum residue levels for spirotetramat in pomegranates and various vegetables (EFSA, 2017) MRL application Regulation (EC) No 2017/626 Reasoned opinion on the modification of the existing maximum residue levels for spirotetramat in various crops (EFSA, 2016) MRL application Regulation (EC) No 2015/399 Reasoned opinion on the modification of the existing MRLs for spirotetramat in olives for oil production (EFSA, 2014c) MRL application Regulation (EC) No 364/2014 Reasoned opinion on the modification of the existing MRLs for spirotetramat in strawberries, bananas, table olives, pineapples and shallots (EFSA, 2013b) MRL application Regulation (EC) No 978/2011 Reasoned opinion of EFSA: Modification of the existing MRLs for spirotetramat in herbs (EFSA, 2011) MRL application Regulation (EC) No 508/2011 Reasoned opinion of EFSA prepared by the Pesticides Unit (PRAPeR) on the modification of existing MRL for spirotetramat in various crops (EFSA, 2010b) MRL application Regulation (EC) No 765/2010 Reasoned opinion of EFSA prepared by the Pesticides Unit (PRAPeR) on the modification of existing MRL for spirotetramat in onions and the setting of new MRLs in kidney (EFSA, 2010a) MRL application Regulation (EC) No 459/2010 Reasoned opinion of EFSA prepared by the Pesticides Unit (PRAPeR) on the modification of existing MRL for spirotetramat in plums and cherries (EFSA, 2009b) MRL application Regulation (EC) No 822/2009 Reasoned opinion of EFSA prepared by the Pesticides Unit (PRAPeR) on the modification of the existing MRLs for spirotetramat in various fruit crops (EFSA, 2009a) Implementation of CAC 2009 Regulation (EC) No 459/2010 CXLs implemented for stone fruits, potatoes, okra, head cabbage, leafy brassicas, lettuces and salad plants, spinaches and similar, water cresses, celery, hops, animal commodities Implementation of CAC 2010 Regulation (EC) No 812/2011 CXLs implemented for tree nuts Implementation of CAC 2012 Regulation (EC) No 293/2013 Scientific report of EFSA. Scientific and technical support for preparing a EU position in the 44th Session of the Codex Committee on Pesticide Residues (CCPR) (EFSA, 2012) CXLs implemented for mangoes, onions, fresh legume vegetables, pulses, soya bean, cotton seed, muscle, mammalian liver, kidney and offals (a lower value of 0.7 mg/kg was legally implemented as a reservation was raised regarding the advanced CXL of 1 mg/kg) Implementation of CAC 2014 Regulation (EC) No 2015/845 Scientific report of EFSA. Scientific and technical support for preparing an EU position in the 46th Session of the Codex Committee on Pesticide Residues (CCPR) (EFSA, 2014b). CXLs implemented for cranberries and globe artichokes. Reservation raised for the CXLs on bush berries MRL: maximum residue level; CXL: codex maximum residue limit. For the purpose of this MRL review, all the uses of spirotetramat currently authorised within the EU and in third countries as submitted by the Member States during the GAP collection, have been reported by the RMS in the GAP overview file. The critical GAPs identified in the GAP overview file were then summarised in the PROFile and considered in the assessment. The details of the authorised critical GAPs for spirotetramat are given in Appendix A. Assessment EFSA has based its assessment on the following documents: the PROFile submitted by the RMS; the evaluation report accompanying the PROFile (Austria, 2019); the draft assessment report (DAR) and its addenda prepared under Council Directive 91/414/EEC (Austria, 2008, 2013b); the conclusion on the peer review of the pesticide risk assessment of the active substance spirotetramat (EFSA, 2013a); the Joint Meeting on Pesticide residues (JMPR) Evaluation report (FAO, 2008, 2011, 2012, 2015); the previous reasoned opinions on spirotetramat (EFSA, 2009a,b, 2010a,b, 2011, 2013b, 2014c, 2016, 2017, 2019a). The assessment is performed in accordance with the legal provisions of the uniform principles for evaluation and authorisation of plant protection products as set out in Commission Regulation (EU) No 546/20118 and the currently applicable guidance documents relevant for the consumer risk assessment of pesticide residues (European Commission, 1997a b, c, d, e, f–g, 2000 2010a, b 2017; OECD, 2011, 2013). More detailed information on the available data and on the conclusions derived by EFSA can be retrieved from the list of end points reported in Appendix B. 1 Residues in plants 1.1 Nature of residues and methods of analysis in plants 1.1.1 Nature of residues in primary crops The metabolism of spirotetramat was investigated after foliar treatment in fruits (apples), leafy (lettuce), roots (potatoes) and pulses/oilseeds (cotton) and assessed in the framework of the peer-review (Austria, 2008; EFSA, 2013a). In all studies, spirotetramat was radiolabelled in the azaspirodecenyl moiety of the molecule. After two foliar applications (BBCH 69/71) of 576 g a.s./ha on apples (fruits) at 63 days after last application (DALA), the major component identified in the fruits was spirotetramat representing 51.3% of the total radioactive residues (TRR) while spirotetramat-monohydroxy was present at 15.6% TRR, spirotetramat-ketohydroxy at 7.7%, spirotetramat-enol-glycoside at 5.1% TRR and spirotetramat-enol at 2.1% TRR. Residue levels of spirotetramat and spirotetramat-monohydroxy in the whole fruit were 0.3 and 0.095 mg eq/kg, respectively (EFSA, 2013a). Spirotetramat-ketohydroxy, spirotetramat-enol-glycoside and spirotetramat-enol were found at 0.047, 0.031 and 0.013 mg eq/kg in fruits (EFSA, 2013a). After three foliar applications (BBCH 75/85/93) of 96 g a.s./ha on potatoes (root crops) at 14 DALA, the parent compound was not detected in tubers but found in tops at 49% TRR. The major component identified in the tubers was spirotetramat-enol, representing 66% of the TRR. Spirotetramat-ketohydroxy was present below 10% TRR (6.8%) in tubers but at 24.8% TRR in tops. Residue levels of spirotetramat-enol were 0.17 mg eq/kg in tubers and 0.86 mg eq/kg in tops (EFSA, 2013a). After two foliar applications (BBCH 41/45) of 72 g a.s./ha on lettuce (leafy crops) at 7 DALA, the major component identified in the leaves was spirotetramat, representing 55.9% TRR, while spirotetramat-enol and its glycoside were present at 17.8 and 11.4% TRR, respectively. Residue levels of spirotetramat, spirotetramat-enol and its glycoside were 1.75, 0.56 and 0.36 mg eq/kg. Spirotetramat-ketohydroxy although representing only 6.2% TRR was present at significant absolute amounts (up to 0.19 mg eq/kg) (EFSA, 2013a). After two foliar applications (BBCH 15/85) of 92 and 172 g a.s./ha on cotton (pulses and oilseeds), at 39 DALA, the parent compound was not detected. The major component identified in undelinted seed was spirotetramat-enol representing 39.8% TRR. Parent compound was present in the whole plant (at 19 days after 1st treatment), gin trash and lint representing 46.9, 19.8 and 32.3% TRR. In gin trash, spirotetramat-enol and spirotetramat-ketohydroxy were also present at 12.1% and 29.7%TRR, respectively. In lint, spirotetramat-ketohydroxy and spirotetramat-mandelic acid amide were present at 10.5 and 11.9% TRR. Residue levels of spirotetramat, spirotetramat-enol, spirotetramat-ketohydroxy and spirotetramat-desmethyl-enol-glucoside were < 0.001, 0.047, 0.011 and 0.004 mg eq/kg in undelinted seed. Parent compound levels in the whole plant (at 19 days after 1st treatment), gin trash and lint were 1.1, 0.32, 0.35 mg eq/kg. In gin trash, levels of spirotetramat-enol, spirotetramat-ketohydroxy, its glycose conjugate and spirotetramat-olefine were 0.2, 0.48, 0.061 and 0.061 mg eq/kg, respectively (EFSA, 2013a). The metabolic pathway of spirotetramat was similar in all crop groups investigated. The major metabolic reactions involved first the hydrolytic cleavage of the ethyl carbonate group to form the metabolite spirotetramat-enol, which is further degraded by oxidation or reduction to form the metabolites spirotetramat-ketohydroxy and spirotetramat-monohydroxy. Additional hydroxylation, oxidation, demethylation and glucoside conjugations result in several supplementary minor metabolites (EFSA, 2013a). 1.1.2 Nature of residues in rotational crops Spirotetramat is authorised on crops that may be grown in rotation. According to the soil degradation field studies assessed during the peer review, the maximum DT90 value for spirotetramat accounts for 3.5 days. The DT90 value for the sum of spirotetramat-enol and spirotetramat-ketohydroxy was calculated to be 105 days; for the sum of spirotetramat, spirotetramat-enol, spirotetramat-ketohydroxy and spirotetramat-MA amide a DT90 of 77.8 days was reported (EFSA, 2013a). Thus, the trigger value of 100 days is slightly exceeded for the sum of spirotetramat-enol and spirotetramat- ketohydroxy and therefore the occurrence of spirotetramat residues in rotational crops was further investigated. One confined rotational crop study with [azaspirodecenyl-3-14C]-spirotetramat was available for this review (Austria, 2008; EFSA, 2013a). Spirotetramat was applied at a rate of 406 g a.s./ha onto bare soil. Spring wheat, swiss chard and turnips were planted at nominal plant-back intervals (PBI) of 30, 135 and 260 days after treatment (DAT). Parent spirotetramat was not observed in any of the samples and spirotetramat-enol was only detected in wheat grain (3% TRR). In all rotated crops, residues were mainly composed of the ketohydroxy, desmethyl-ketohydroxy and desmethyl-dihydroxy metabolites and their conjugates, accounting respectively for up to 31% of TRR (wheat forage), 32% of TRR (wheat forage) and 18% of TRR (wheat forage and hay). Based on this study, the peer review concluded that the metabolism and distribution of spirotetramat in rotational crops is similar to the metabolic pathway observed in primary crops (EFSA, 2013a). This conclusion is still supported in the framework of this review. 1.1.3 Nature of residues in processed commodities Studies investigating the nature of residues in processed commodities were assessed during the peer review (EFSA, 2013a). Studies were conducted with spirotetramat, spirotetramat-enol, spirotetramat-enol-glucoside, spirotetramat-monohydroxy and spirotetramat-ketohydroxy radiolabelled on the azaspirodecenyl-ring simulating representative hydrolytic conditions for pasteurisation (20 min at 90°C, pH 4)
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