Normativa UEJul. 3, 2013
UE: revisan límites máximos de residuo para imazamox
Imazamox was included in Annex I to Directive 91/414/EEC on 01 July 2003, which is before the entry into force of Regulation (EC) No 396/2005 on 02 September 2008. EFSA is therefore required to provide a reasoned opinion on the review of the existing MRLs for that active substance in compliance with Article 12(2) of the aforementioned regulation. In order to collect the relevant pesticide residues data, EFSA asked France, as the designated rapporteur Member State (RMS), to complete the Pesticide Residues Overview File (PROFile). The requested information was submitted to EFSA on 11 June 2009 and, after having considered several comments made by EFSA, the RMS provided on 19 October 2012 a revised PROFile.
Based on the conclusions derived in the framework of Directive 91/414/EEC and the additional information provided by the RMS, EFSA issued on 24 January 2013 a draft reasoned opinion that was circulated to Member States’ experts for consultation. Comments received by 29 March 2013 were considered in the finalisation of this reasoned opinion. The following conclusions are derived.
The toxicological profile of imazamox was evaluated in the framework of Directive 91/414/EEC, which resulted in an ADI being established at 9.0 mg/kg bw per d. An ARfD was not deemed necessary.
Metabolism of imazamox was investigated for soil application, pre-emergence treatment (via incorporation to soil) and by foliar application post emergence on cereals (maize) and on pulses and oilseeds (soya bean, pea and oilseed rape), using 6-pyridine-14C labelled-imazamox. The fate of the imidazolinone moiety was not addressed in the submitted plant metabolism studies and needs to be further addressed. Nevertheless, in the absence of significant residues of parent imazamox and any degradation products (using the pyridine label), it is considered that the residue for enforcement and risk assessment in pulses and oilseeds and cereal grain is tentatively defined as parent imazamox only, which is sufficient to cover the authorised uses. Analytical methods for enforcement of the proposed residue definition in high water content, acidic and dry commodities are available but a confirmatory method and a validated analytical method for enforcement of residue in high oil content commodities are still required. With regard to the authorisation of further uses confirmation that the hydroxymethyl metabolite does not occur in practice will be required. In fodder the levels of the hydroxymethyl metabolite and the glucoside metabolite, were greater than that for the parent imazamox. The residue for risk assessment in fodder commodities is therefore tentatively proposed as the sum of imazamox and its hydroxymethyl metabolite free and conjugated expressed as imazamox. This residue definition is also proposed for enforcement purposes in view of the future need to set MRLs in feed items and a validated analytical method for enforcement of the proposed future residue definition in forage crops may still be required by risk managers in the future.
Regarding the magnitude of residues in crops, the available residues data are considered sufficient to derive MRL proposals as well as risk assessment values for all commodities under evaluation, except for rice where the available data were insufficient to derive tentative MRLs. MRL proposals are in any case considered on a tentative basis only due to the lack of a metabolism study with labelling of the imidazolinone ring and due to the analytical method deficiencies for enforcement in oilseeds (see above).
As residues of imazamox exceeding 0.1 mg/kg are not expected in the treated crops and the chronic exposure does not exceed 10 % of the ADI, there is no need to investigate the effect of industrial and/or household processing.
Occurrence of imazamox residues in rotational crops was investigated. It is concluded that significant residues in rotational crops are not expected, provided that imazamox is applied according to the GAPs supported in the framework of this review.
Based on the uses reported by the RMS, significant exposures to imazamox are expected for dairy and meat ruminants and pigs. A metabolism study for goat confirms an expectation that residue levels in livestock commodities (excluding poultry) are expected to remain below the enforcement LOQ of 0.01 mg/kg and a residue definition of parent imazamox only is proposed for dairy and meat ruminants and pigs. However validated analytical methods for enforcement of the proposed residue definition in food of animal origin are not available. In the absence of an analytical method of analysis for enforcement of imazamox in food of animal origin with a validated LOQ it is considered that the MRL be established at the default value of 0.01 mg/kg. MRLs for poultry products are not required because they are not expected to be exposed to significant levels of imazamox residues.
Chronic consumer exposure resulting from the uses authorised in the framework of this review was calculated using revision 2 of the EFSA PRIMo. The highest chronic exposure represented 0.005 % of the ADI (Dutch children). Acute exposure calculations were not carried out because an ARfD was not deemed necessary for this active substance.
Based on the above assessment, EFSA does not recommend inclusion of this active substance in Annex IV to Regulation (EC) No 396/2005. MRL recommendations were derived in compliance with the decision tree reported in Appendix D of the reasoned opinion (see summary table). All MRL values listed as ‘Recommended’ in the table are sufficiently supported by data and are therefore proposed for inclusion in Annex II to the Regulation. The remaining MRL values listed in the table are not recommended for inclusion in Annex II because they require further consideration by risk managers (see summary table footnotes for details). In particular, tentative MRLs need to be confirmed by the following data:
a validated method of analysis for the determination of imazamox residues in high oil content crops and a confirmatory method for the determination of imazamox residues in high oil content, high water content, acidic and dry crops (will be considered as part of the active substance renewal program scheduled for 2014);
a validated method of analysis for the determination of imazamox residues in commodities of animal origin (supported by independent laboratory validation data and a confirmatory method);
representative plant metabolism studies with imazamox labelled at the imidazolinone ring (will be considered as part of the active substance renewal program scheduled for 2014);
7 additional residues trials supporting the southern outdoor GAP on rice;
If the above reported data gaps are not addressed in the future, Member States are recommended to withdraw or modify the relevant authorisations at national level.
Minor deficiencies were also identified in the assessment but these deficiencies are not expected to impact either on the validity of the MRLs derived or on the national authorisations. The following actions and data are therefore considered desirable but not essential:
information on the storage conditions for all residues trials samples reported in the framework of this review.