Normativa UEJul. 3, 2013
UE: revisan límites máximos de residuo para diflufenican
Diflufenican was included in Annex I to Directive 91/414/EEC on 01 January 2009, which is after 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(1) of the aforementioned regulation. In order to collect the relevant pesticide residues data, EFSA asked United Kingdom, as the designated rapporteur Member State (RMS), to complete the Pesticide Residues Overview File (PROFile) and to prepare a supporting evaluation report. The requested information was submitted to EFSA on 09 September 2010 and, after having considered several comments made by EFSA, the RMS provided on 20 April 2012 a revised PROFile.
Based on the conclusions derived by EFSA in the framework of Directive 91/414/EEC and the additional information provided by the RMS, EFSA issued on 07 February 2013 a draft reasoned opinion that was circulated to Member States’ experts for consultation. Comments received by 12 April 2013 were considered in the finalisation of this reasoned opinion. The following conclusions are derived.
The toxicological profile of diflufenican was evaluated in the framework of Directive 91/414/EEC, which resulted in an ADI being established at 0.2 mg/kg bw per d. An ARfD was not deemed necessary for this active substance.
Primary crop metabolism of diflufenican was investigated in wheat following pre- and post-emergence applications and in olives following soil application. The relevant residue for both enforcement and risk assessment for fruit and fruiting vegetables, cereals (grain and straw) and ryegrass was proposed as parent diflufenican only. However the use of diflufenican by foliar application is also authorised in peas, which do not belong to the aforementioned groups. An additional metabolism study is therefore required in order to confirm the proposed residue definition for pulses and oilseeds as well. Validated analytical methods for enforcement of the residue definition in foods of plant origin are available with an LOQ of 0.01 mg/kg in high water, high oil, acidic and dry commodities.
Regarding the magnitude of residues in table olives, olives for oil production and small grain cereals, GAPs were supported by a sufficient number of supervised residue trials, which allowed EFSA to estimate the expected residue concentrations in the relevant plant commodities. However, for citrus fruits, almonds, walnuts, pome fruits, stone fruits, table and wine grapes, and kiwi, additional storage stability data are still required and only tentative MRLs were derived. For cane fruits and other small fruits and berries, peas (fresh and dry), millet and grass, the number of residue trials was not sufficient to derive MRL proposals and further residue trials are required.
As residues of diflufenican are in most cases below 0.1 mg/kg and contribution of these residues to chronic consumer exposure is generally low, investigating the effect of industrial and/or household processing was not considered necessary.
Occurrence of diflufenican residues has been investigated in rotational crops sown/planted 12 weeks after an application of 0.36 kg a.s./ha on a bare soil. The presence of metabolite AE B107137 at levels above 0.01 mg/kg in root crops cannot be excluded.Therefore, further investigation on the levels of diflufenican and its metabolite AE B107137 in succeeding crops (particularly in root crops) is required. Meanwhile, appropriate risk mitigation measures might be taken at national level in order to avoid the occurrence of diflufenican residues in rotational crops. Based on the metabolism study, a waiting period of 150 days before planting root crops seems the most appropriate.
Based on the uses reported by the RMS, significant intakes were calculated for ruminants. Metabolism in lactating ruminants and poultry was sufficiently investigated and findings can be extrapolated to pigs as well. The relevant residue definition for both enforcement and risk assessment in livestock was therefore defined as diflufenican. These studies also demonstrated that residues of diflufenican are not expected and MRLs can be set at the LOQ. Although not fully validated, analytical methods for enforcement of the residue definition in foods of animal origin are available with an LOQ of 0.02 mg/kg in meat, fat, liver, kidney and eggs and an LOQ of 0.01 mg/kg in milk.
Chronic consumer exposure resulting from the authorised uses reported in the framework of this review was calculated using revision 2 of the EFSA PRIMo. For those commodities where data were insufficient to derive an MRL, EFSA considered the existing EU MRL for an indicative calculation. The highest chronic exposure represented 0.3 % 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, some tentative MRLs or existing EU MRLs still need to be confirmed by the following data:
a confirmatory method for enforcement of diflufenican in food of animal origin;
a representative study investigating primary crop metabolism in a third crop group, preferably pulses and oilseeds;
a storage stability study for acidic commodities and for commodities with high water content covering the storage period of the reported trials (as residues trials on fruits were also used to propose an MRL for walnuts and almonds, this data gap also applies to these tree nuts);
further clarification on the northern outdoor GAP authorised on small fruits and berries (growth stage at application) as well as 4 residue trials on strawberries and 4 residue trials on either grapes, blackcurrants or other berries supporting this GAP (mainly impacting MRLs for strawberries, cane fruit and other small fruits and berries);
8 residue trials on fresh peas with pods supporting the northern outdoor GAP on fresh peas with and without pods as well as dry peas;
4 residue trials supporting the northern outdoor GAP on millet.
It is highlighted, however, that some of the MRLs derived result from a GAP in one climatic zone only, while other GAPs reported by the RMS were not fully supported by data. EFSA therefore identified the following data gaps which are not expected to impact on the validity of the MRLs derived but which might have an impact on national authorisations:
further clarification on the northern outdoor GAP authorised on stone fruits (growth stage at application) as well as 4 residue trials on apples and 4 residue trials on stone fruits supporting the GAPs on pome fruit and stone fruit;
investigation on the levels of diflufenican and its metabolite AE B107137 in succeeding crops (particularly in root crops);
4 residue trials supporting the southern outdoor GAP and 4 residue trials supporting the northern outdoor GAP on ryegrass.
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. Regarding rotational crops in particular, Member States granting authorisations for diflufenican should consider appropriate risk mitigation measures such as a waiting period of 150 days before planting of root crops.