Modification of the existing maximum residue levels for bentazone in soyabeans and poppy seeds
2019; Wiley; Volume: 17; Issue: 8 Linguagem: Inglês
10.2903/j.efsa.2019.5798
ISSN1831-4732
AutoresMaria Anastassiadou, Alba Brancato, Luis Carrasco Cabrera, Lucien Ferreira, Luna Greco, Samira Jarrah, Aija Kazocina, Renata Leuschner, José Oriol Magrans, Ileana Miron, Stéfanie Nave, Ragnor Pedersen, Hermine Reich, Angela Sacchi, Miguel Santos, Alois Stanek, Anne Theobald, Bénédicte Vagenende, Alessia Verani,
Tópico(s)Vitamin K Research Studies
ResumoEFSA JournalVolume 17, Issue 8 e05798 Reasoned OpinionOpen Access Modification of the existing maximum residue levels for bentazone in soyabeans and poppy seeds European Food Safety Authority (EFSA), European Food Safety Authority (EFSA)Search for more papers by this authorMaria Anastassiadou, Maria AnastassiadouSearch 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 authorLucien Ferreira, Lucien FerreiraSearch 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 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), European Food Safety Authority (EFSA)Search for more papers by this authorMaria Anastassiadou, Maria AnastassiadouSearch 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 authorLucien Ferreira, Lucien FerreiraSearch 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 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: 02 August 2019 https://doi.org/10.2903/j.efsa.2019.5798Citations: 1 Correspondence: pesticides.mrl@efsa.europa.eu Requestor: European Commission Question number: EFSA-Q-2018-00734 Approved: 8 July 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 In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant BASF SE submitted an application to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for bentazone in soyabeans and poppy seeds. The data submitted in support of the request were found to be sufficient to derive MRL proposals for both commodities. Adequate analytical methods for enforcement are available to control the residues of bentazone and its metabolites in plant matrices under consideration. The studies requested by EFSA in the framework of the peer review to address the toxicological properties of metabolite 6-hydroxy-bentazone were only partially provided. Instead of studies investigating the general toxicity of this metabolite, the applicant provided an argumentation to justify read-across from the available information on parent bentazone and 8-hydroxy-bentazone. EFSA did not agree with the provided reasoning for read-across. Therefore, the EMS asked EFSA to continue the assessment despite the data gap. EFSA performed an indicative short-term and long-term dietary risk assessment; the calculated dietary exposure was well below the toxicological reference values. The risk assessment however is affected by additional, non-standard uncertainties resulting from data gap related to the toxicological properties for 6-hydroxy-bentazone. Summary In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant BASF SE submitted an application to the competent national authority in the Netherlands (evaluating Member State, EMS) to set maximum residue levels (MRLs) for bentazone in poppy seeds and soyabeans on the basis of intended European uses. The EMS drafted an evaluation report in accordance with Article 8 of Regulation (EC) No 396/2005, which was submitted to the European Commission and forwarded to the European Food Safety Authority (EFSA) on 25 September 2018. The EMS proposed to set an MRL for bentazone in soyabeans and poppy seeds at the level of 0.2 mg/kg. EFSA assessed the application and the evaluation report as required by Article 10 of the MRL regulation. EFSA identified data gaps and points which needed further clarification, which were requested from the EMS. On 10 May 2019, the EMS submitted a revised evaluation report, which replaced the previously submitted evaluation report. According to EFSA, the data gap related to the toxicological profile of 6-hydroxy-bentazone was not fully addressed. The EMS, who did not agree with EFSA's views, asked EFSA to continue the assessment despite the data gap, and to outline the divergent views on 6-hydroxy-bentazone and the related impact on the risk assessment. Based on the conclusions derived by EFSA in the framework of Regulation (EC) 1107/2009, the data evaluated under previous MRL assessments and the additional data provided by the EMS in the framework of this application, the following conclusions are derived. The metabolism of bentazone following foliar treatment was investigated in the framework of the renewal of the approval of bentazone in crops belonging to the groups of root crops (potatoes), cereals/grass (rice, wheat, maize) and pulses and oilseeds (soyabean). The nature of bentazone in rotational crops (radish, lettuce and wheat) was investigated following soil treatment and indicated a similar metabolic pathway as in primary crops. In the framework of the peer review, an additional study with wheat treated as primary crop and grown in rotation with treated potatoes was assessed. The study represents a worst-case agriculture practice. For this study, the peer review set a data gap regarding an unidentified metabolite fraction M3 in wheat straw. New information on the identity of fraction M3 has not been provided to EFSA. The lack of this information is not expected to affect the current assessment as the forages of soyabeans and poppy seeds are not used as livestock feed in Europe. Based on the metabolic pattern identified in metabolism studies and the toxicological significance of metabolites, the peer review on the renewal of the approval proposed 'bentazone' as the relevant residue for enforcement. For the risk assessment, a residue definition was proposed as 'sum of bentazone, 6-hydroxy-bentazone and its conjugates, expressed as bentazone'. This residue definition is provisional, pending the clarification of the identity of metabolite fraction M3 in the wheat metabolism study and lacking the full toxicological information on 6-hydroxy-bentazone to conclude whether separate toxicological reference values are necessary for this metabolite. As the residue definitions derived by the peer review are not yet enforced, EFSA derived MRL proposals for the enforcement residue definition established in the Regulation (EC) No 396/2005 (sum of bentazone, its salts, 6-hydroxy-bentazone (free and conjugated) and 8-hydroxy-bentazone (free and conjugated), expressed as bentazone) as well as for the proposed new, provisional residue definition. The risk assessment was performed for the current residue definition that comprises also 8-hydroxy-bentazone (free and conjugated), which is considered to give a more conservative result. Studies investigating the effect of processing on the nature of bentazone (standard hydrolysis studies) are not available and are not currently required, considering the low consumer exposure to bentazone residues related to the crops under assessment. Sufficiently validated analytical methods are available to quantify residues in the crops assessed in this application according to the enforcement residue definition. The available residue trials are sufficient to derive an MRL proposal of 0.2 mg/kg for bentazone (sum of bentazone, its salts, 6-hydroxy-bentazone (free and conjugated) and 8-hydroxy-bentazone (free and conjugated), expressed as bentazone) in soyabeans and poppy seeds in support of a more critical northern Europe (NEU) use. The same MRL proposal is appropriate for the proposed new residue definition that covers only parent bentazone. Since by-products of soyabeans can be fed to livestock, the potential carry-over of residues into food of animal origin was assessed. The livestock dietary burden was calculated according to the OECD methodology. Comparing the results with the results of the dietary burden calculated recently in the framework of the assessment of the Article 12 confirmatory data, where the calculations were performed using the EU methodology, a slightly lower exposure for cattle and sheep and a higher exposure for swine and poultry was estimated. The difference was caused by the different calculation methodology. The contribution of bentazone residues in soyabeans to the livestock exposure is insignificant. EFSA derived MRL proposals following the OECD methodology. While the MRL proposals derived in the assessment of Article 12 confirmatory data were confirmed for some animal products, such as meat and fat of swine, cattle, sheep, goat and equine, lower MRLs would be sufficient for liver and kidney of swine, cattle and sheep and for milk of cattle. In poultry commodities, no residues above the limit of quantification (LOQ) are expected to occur. The toxicological profile of bentazone, 6-hydroxy-bentazone and 8-hydroxy bentazone was assessed during the renewal of the approval process of bentazone. New toxicological reference values were derived for bentazone as an acceptable daily intake (ADI) of 0.09 mg/kg body weight (bw) per day and an acute reference dose (ARfD) of 1 mg/kg bw, which are applicable also to the metabolite 8-hydroxy-bentazone. Regarding the metabolite 6-hydroxy-bentazone, no conclusion could be reached. While in the present application, the genotoxicity potential of this metabolite has been clarified with a QSAR analysis and read across, EFSA is of the opinion that the general toxicity of the metabolite could not be concluded on the basis of the information provided. EFSA performed an indicative consumer risk assessment with revision 3.1 of the EFSA Pesticide Residues Intake Model (PRIMo), considering the currently applicable risk assessment residue definitions for plant and animal commodities. The input values for the chronic exposure calculation for soyabeans and poppy seeds were the STMR values as derived from the residue trials submitted for the current assessment. For the remaining plant and animal origin commodities, the input values were those considered in the recent EFSA opinion on the evaluation of confirmatory data following the Article 12 MRL review for bentazone. The acute exposure assessment was performed only for soyabeans and poppy seeds, considering the STMR values as derived from the residue trials submitted for the current assessment. The risk assessment is indicative because of the data gap on the general toxicity for 6-hydroxy-bentazone. No long-term consumer intake concerns were identified for the intended and the authorised uses of bentazone, as the estimated maximum long-term dietary intake accounted for 3% of the ADI (NL toddler diet). The maximum short-term exposure to oilseeds under consideration was insignificant (< 0.01% of the ARfD for soyabeans and poppy seeds, respectively). According to the exposure assessment, it is unlikely that the proposed use of bentazone on soyabeans and poppy seeds will result in a consumer exposure exceeding the toxicological reference values. However, the risk assessment is affected by additional, non-standard uncertainties. The assessment of the confirmatory data following the peer review of the active substance is not yet finalised and therefore the conclusions reported in this reasoned opinion might need to be reconsidered in the light of the outcome of that assessment. The conclusions of the assessment are summarised in the table below. Full details of all end points and the consumer risk assessment can be found in Appendices B, B, B–D. Codea Commodity Existing MRL Proposed MRL Conclusion/recommendation Existing enforcement residue definition: Bentazone (sum of bentazone, its salts, 6-hydroxy-bentazone (free and conjugated) and 8-hydroxy-bentazone (free and conjugated), expressed as bentazone) Proposed new residue definition (not yet implemented): Bentazone 0401030 Poppy seeds 0.03* 0.2/0.2 Further risk management considerations required The submitted residue data are sufficient to derive an MRL proposal for the intended NEU use. According to the indicative dietary risk assessment, no consumer intake concerns were identified. Further risk management considerations required, considering that the general toxicity of 6-hydroxy-bentazone is not fully characterised 0401070 Soyabeans 0.03* 0.2/0.2 Further risk management considerations required The submitted residue data are sufficient to derive an MRL proposal for the new intended NEU/SEU uses. The MRL reflects the more critical NEU use. According to the indicative dietary risk assessment, no consumer intake concerns were identified. Further risk management considerations required, considering that the general toxicity of 6-hydroxy-bentazone is not fully characterised Existing enforcement residue definition: Sum of bentazone, its salts and 6-hydroxy-bentazone (free and conjugated), expressed as bentazone 1011040 Swine kidney 0.05/0.03b 0.02 Further risk management considerations required The MRL proposals were derived based on the revised dietary burden calculation according to the OECD methodology including the new use on soyabeans. The MRLs for other animal products derived in the recently published EFSA reasoned opinion on the evaluation of the Article 12 confirmatory data for bentazone were confirmed. According to the indicative dietary risk assessment, no consumer intake concerns identified. Further risk management considerations required, considering that the general toxicity of 6-hydroxy-bentazone is not fully characterised 1012030 1013030 1014030 1015030 Liver: Bovine Sheep Goat Equine 0.02*/0.05b 0.03 (cattle) 0.04 (sheep) Further risk management considerations required 1012040 1013040 1014040 1015040 Kidney: Bovine Sheep Goat Equine 0.3/0.3b 0.15 Further risk management considerations required 1020000 Milk 0.02*/0.03b 0.02*(cattle) 0.03 (sheep) Further risk management considerations required MRL: maximum residue level; NEU: northern Europe; SEU: southern Europe; OECD: Organisation for Economic Co-operation and Development. * Indicates that the MRL is set at the limit of analytical quantification (LOQ). a Commodity code number according to Annex I of Regulation (EC) No 396/2005. b The MRL proposals derived in the EFSA reasoned opinion on the evaluation of the Article 12 confirmatory data for bentazone (EFSA, 2019b). Assessment The detailed description of the intended Good Agricultural Practices (GAPs) of bentazone on poppy seeds and soyabeans, which are the basis for the current maximum residue level (MRL) application, is reported in Appendix A. Bentazone is the ISO common name for 3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide (IUPAC). The chemical structures of the active substance and its main metabolites are reported in Appendix E. Bentazone was first evaluated in the framework of Directive 91/414/EEC1 with Germany designated as rapporteur Member State (RMS) for the representative uses as outdoor foliar spraying against annual dicotyledonous weeds in various crops. In 2018, the approval for bentazone has been renewed,2 following the peer review process in the framework Reg. (EC) No 1107/20093 with the Netherlands as the new RMS (Netherlands, 2013; EFSA, 2015). The review of existing MRLs for the active substance bentazone according to Article 12 of Regulation (EC) No 396/20054 (MRL review) has been performed in 2012 prior the renewal of the approval of bentazone (EFSA, 2012). The MRL proposals of the MRL review were implemented in the Commission Regulation (EU) No 1146/20145 along with confirmatory data to be addressed by the applicants. Recently an EFSA reasoned opinion was issued on the evaluation of Article 12 confirmatory data of bentazone (EFSA, 2019b). In accordance with Article 6 of Regulation (EC) No 396/2005, BASF SE submitted an application to the competent national authority in the Netherlands (evaluating Member State, EMS) to modify the existing European Union (EU) MRLs for bentazone in poppy seeds and soyabeans in support of the new intended EU uses. The EMS drafted an evaluation report in accordance with Article 8 of Regulation (EC) No 396/2005, which was submitted to the European Commission and forwarded to the European Food Safety Authority (EFSA) on 25 September 2018. The EMS proposed to set an MRL for bentazone in soyabeans and poppy seeds at 0.2 mg/kg. EFSA assessed the application and the evaluation report as required by Article 10 of the MRL regulation. EFSA identified data gaps or points which needed further clarifications, which were requested from the EMS. The EMS did not agree with certain points for which further information was requested, and asked EFSA to resume the assessment based on the information provided in the revised evaluation report submitted on 10 May 2019 (Netherlands, 2018). EFSA considered that the data gap related to the toxicological profile of 6-hydroxy-bentazone was not fully addressed and finalised the reasoned opinion considering the different view expressed by the EMS on 6-hydroxy-bentazone and the related impact on the risk assessment. EFSA based its assessment on the evaluation report submitted by the EMS (Netherlands, 2018), the conclusions from the review of the existing MRLs according to Article 12 of Regulation (EC) No 396/2005 (EFSA, 2012), the Renewal Assessment Report (RAR) prepared under Regulation (EC) 1107/2009 (Netherlands, 2013), the conclusion on the peer review of the pesticide risk assessment of the active substance bentazone (EFSA, 2015), as well as the Commission review report on bentazone (European Commission, 2018). For this application, the data requirements established in Regulation (EU) No 544/20116 and the guidance documents applicable at the date of submission of the application to the EMS are applicable (1997a,b, c, d, e, f, g, 2000a,b, 2010a, b, 2017; OECD, 2011, 2013). The assessment is performed in accordance with the legal provisions of the Uniform Principles for the Evaluation and the Authorisation of Plant Protection Products adopted by Commission Regulation (EU) No 546/20117. A selected list of end points of the studies assessed by EFSA in the framework of this MRL application including the end points of relevant studies assessed previously, submitted in support of the current MRL application, are presented in Appendix B. The evaluation report submitted by the EMS (Netherlands, 2018) and the exposure calculations using the EFSA Pesticide Residues Intake Model (PRIMo) are considered as supporting documents to this reasoned opinion and, thus, are made publicly available as background documents to this reasoned opinion. 1 Mammalian toxicology The toxicological reference values of bentazone were reviewed under the renewal of the approval of the active substance bentazone in 2015. The acceptable daily intake (ADI) of bentazone was established at 0.09 mg/kg body weight (bw) per day, based on the no observed adverse effect level (NOAEL) of 9 mg/kg bw per day for blood, liver and kidney toxicity observed in the 2-year study in rats and applying the standard uncertainty factor (UF) of 100. The acute reference dose (ARfD) was established at 1 mg/kg bw, based on the NOAEL of 100 mg/kg bw per day for increased post-implantation loss, reduced number of live fetuses and retarded fetal development observed in a developmental toxicity study in rats, 100 UF applied (EFSA, 2015). The toxicological properties of metabolites included in the risk assessment residue definition were also assessed during the procedure of renewal of the approval. The peer review concluded that 8-hydroxy-bentazone is relatively less toxic than the parent bentazone from the acute, short-term and developmental toxicity point of view and is unlikely to be genotoxic. The toxicological reference values of the parent apply to this metabolite (EFSA, 2015). Regarding 6-hydroxy-bentazone, insufficient toxicological information (acute toxicity studies in rat and mouse, as well as an Ames test) was available during the renewal of approval of bentazone and a data gap was identified by the peer review for further data to derive toxicological reference values (EFSA, 2015). This means that the clastogenic/aneugenic potential, and repeated-dose toxicity of 6-hydroxy-bentazone have to be addressed by appropriate toxicological data. For this metabolite, in support of the current MRL application, the applicant provided a QSAR analysis using combination of a statistical model (Case Ultra ver. 1.7.0.5) and expert knowledge system (DEREK Nexus ver. 2.2). The end points predicted were in vivo micronucleus (Case Ultra model) and in vitro and in vivo chromosomal damage (Derek Nexus model). Negative predictions were obtained from both models. It should be mentioned that in order to straighten the reliability of the predictions the applicant has expanded the applicability domain of the statistical model to pesticides chemistry by including in the training set substances from EFSA Genotoxicity database as well as from their own proprietary plant protection database. Although the full details of the model are not reported in the evaluation report, e.g. whether only validated in vivo experimental data were used for which the bioavailability of the test substance to the bone marrow was demonstrated and of the statistical performance of the model, EFSA agrees with the EMS that based on the QSAR analysis it can be concluded that 6-hydroxy-bentazone is unlikely to be genotoxic with regards to chromosome aberration and aneugenicity in vivo. In addition, read across with bentazone and 8-hydroxy-bentazone is acceptable regarding genotoxicity considering that no alerts were found in any of these compounds, which did not exhibit genotoxic concerns based on experimental data and the different position of the hydroxy group in the aromatic ring is not expected to lead to positive chromosomal damage potential. Taking the QSAR predictions supported by read across and the negative Ames test into account, 6-hydroxy-bentazone is unlikely to be genotoxic. Regarding general toxicity, EFSA does not agree with the EMS conclusion that based on read-across with bentazone and 8-hydroxy-bentazone, 6-hydroxy-bentazone is considered to be not more toxic than the parent (Netherlands, 2018). On one hand, the QSAR analysis does not inform on the relative toxicity of the test compound and on the other hand, the configuration of 6-hydroxy-bentazone (hydroxy group in the para-position) could potentially lead to a different reactivity and to different steric interactions of the molecule compared to the ortho-position of 8-hydroxy-bentazone and accordingly a higher toxicity of the metabolite compared with 8-hydroxy-bentazone and the parent bentazone could not be excluded. The External Scientific Report on the impact of metabolic and degradation processes on the toxicological properties of residues of pesticides in food commodities (Bergmann et al., 2010), reports similar toxicity for hydroxylation on another ring position based on acute toxicity studies, these studies are of low relevance to consumer exposure unlike repeated-dose toxicity studies; the report also notes that 'one and the same metabolic step can cause detoxification of one substance and toxification of another'. According to EFSA, on the basis of the available information, no conclusion can be drawn whether the toxicological reference values of the parent bentazone are applicable to the metabolite 6-hydroxy-bentazone. It is noted that the toxicity of this metabolite was discussed by risk managers in the framework of the renewal of the approval of bentazone, taking into account the conclusions of JMPR (FAO, 2012). According to JMPR, 8-hydroxy-bentazone and 6-hydroxy-bentazone are of comparable toxicity by oral route of administration and both metabolites are less toxic than the parent compound (European Commission, 2018). For the reasons outlined above, EFSA does not share the view of JMPR. 2 Residues in plants 2.1 Nature of residues and methods of analysis in plants 2.1.1 Nature of residues in primary crops The metabolism of bentazone following foliar application was investigated in the framework of the renewal of the approval according to Regulation (EC) 1107/2009 in pulses/oilseed (soyabeans), root and tuber crops (potatoes) and cereals/grass (rice, maize, wheat), using 14C-phenyl labelled bentazone (EFSA, 2015). Parent bentazone was hardly ever detected in any crop part (maximum 8% of the total radioactive residues (TRR)), except in wheat forage and straw (up to 56% TRR). The metabolite 6-hydroxy-bentazone in its conjugated form was also identified in significant proportions, mainly in the feed commodities (24% TRR in maize forage up to 41% TRR in wheat hay), while the glucoside conjugate of 8-hydroxy-bentazone was detected in soyabean forage and in wheat straw, but at lower levels (28% TRR and 3% TRR, respectively). The major part of the radioactivity in the soyabean seeds, potato tuber and cereal grain was found to be incorporated into natural plant constituents (up to 70% TRR). An additional metabolism study with foliar treated wheat, grown as a rotational crop following the harvest of potatoes which were also treated with bentazone, was submitted in the framework of the renewal of the approval. In potato tubers (primary crop), numerous fractions were recovered at a level > 10% of TRR, which were not further identified as their actual levels were mostly below 0.01 mg/kg and consisted mainly of a mixture of polar compounds. In wheat straw, a significant unidentified fraction M3 (57% TRR – 1.1 mg eq./kg) was found; the peer review identified a data gap requesting further attempts to characterise and identify this fraction based on all analytical evidence available from the wheat metabolism study and considering also the potential uptake by the plants of soil metabolites (EFSA, 2015). New information related to the identity of the fraction M3 has not been provided in the framework of the current MRL application. The lack of this information is not expected to affect the current assessment as the forages of soyabeans and poppy seeds are not used as livestock feed in Europe. The metabolic pathway of bentazone in plants consisted mainly of hydroxylation of the parent molecule to form the metabolites 6-hydroxy and 8-hydroxy-bentazone, followed by an O-glycosylation conjugation step (EFSA, 2015). 2.1.2 Nature of residues in rotational crops Soyabeans and poppy seeds can be grown in a crop rotation. During the renewal of the approval of bentazone, the studies investigating the rate of degradation of bentazone in soil were assessed, indicating faster degradation of bentazone under field conditions (DT90 of 87 days) than under laboratory conditions (DT90 of 163 days). In the soil, a minor metabolite (N-methyl-bentazone, 2.4–5.7% of applied radioactivity (AR)) was identified, which exhibits higher persistence in the soil than parent bentazone, with maximum DT90 accounting for up to 508 days, being above the threshold limit of 100 days (EFSA, 2015). The metabolism of bentazone in rotational crops was investigated in the framework of the renewal of the approval of bentazone according to Regulation (EC) 1107/2009 (EFSA, 2015). In the confined rotational crop metabolism studies on leafy crops, root crops and cereals after a bare soil application of 14C-phenyl labelled bentazone at 1 kg/ha the radioactive residues were characterised as polar fractions which were further incorporated into the natural compounds of the plant tissues (30% o
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