EFSA proposes ‘comprehensive review’ of MRLs for dimethoate

Following a request by France for taking emergency measures with regard to the use of dimethoate on vegetables and orchards/fruits and the placing on the market of cherries from Member States or third countries where the use of such plant protection products is authorised, EFSA was asked by the European Commission to perform a preliminary chronic risk assessment for dimethoate, considering the existing EU MRLs and all available information on residues of dimethoate-related metabolites, in particular omethoate; all available information useful for this assessment should be taken into account. In addition, a preliminary acute risk assessment for dimethoate in cherries, and other crops mentioned in the background document provided by France (i.e. asparagus, chicory roots, head cabbage, Brussels sprouts, carrots, turnips, onions, garlic, shallots, celery, celeriac, herbs, sugar beets, olives) should be performed. 

 

Based on the limited information available to EFSA at this time, EFSA concludes that a potential longterm consumer health risk resulting from residues related to the use of dimethoate-containing plant protection products cannot be excluded. There are indications that the exposure related to the parent compound and omethoate may not exceed the ADI, taking into account information that can be used for refinement of the intake calculation (estimated exposure: 87% of the ADI). As essential information on the actual uses in the EU and on the occurrence of additional metabolites that may contribute to the overall long-term exposure is not available at time, and considering the narrow safety margin of the ADI, these calculations cannot be understood as evidence that dimethoate-related residues are not posing a long-term consumer health risk. 

 

As regards the acute risk resulting from all dimethoate-related residues in the crops under consideration, a final conclusion cannot be derived without detailed information on the occurrence of residues of dimethoate, omethoate and other metabolites present on crops treated in accordance with Good Agricultural Practices. 

 

As regards dimethoate and omethoate residues, there is currently no evidence of consumer risks for asparagus, chicory roots, head cabbage, Brussels sprouts, onions, garlic, shallots, celeriac, herbs, based on the risk assessment screening and the analysis of pesticide monitoring data. The contribution of other relevant metabolites may alter that assessment. The risk assessment screening however indicated that the current MRLs set for a number of crops (i.e. spring onions, table olives, fennel seed, potatoes, melons, oranges, olives for oil production, cherries, watermelons, and pineapples) for the current legal residue definition may not be sufficiently protective for consumers. A more detailed risk assessment would be required to confirm or reject the possible concerns. 

 

The French observation that the results of the pesticide monitoring programmes show a higher MRL exceedance rate for dimethoate compared with other pesticides is confirmed by EFSA. The reasons for these findings are not completely clear; possible explanations are: 

 

• Use of dimethoate-containing pesticides that do not respect the authorised Good Agricultural Practices; 

• The existing MRLs are set at inappropriate levels; thus, if farmers use the products in accordance with Good Agricultural Practices, the harvested products may contain residues that exceed the legal limit. 

 

In order to elucidate the reasons for the increased frequency of MRL exceedances, the competent national authorities should establish follow-up actions at the level of the pesticide users. If a misuse of dimethoate can be excluded, these findings suggest that, for certain crops, the current EU MRLs are set at inappropriate levels. 

 

EFSA concludes that a comprehensive review of the existing EU MRLs would be appropriate. This review is planned under Article 12 of Regulation (EC) No 396/2005. However, for this review the following information would be required: 

 

• Toxicological data that allow the assessment of which metabolites need to be included in the residue definitions for acute and chronic risk assessment;

• Toxicity of the metabolites relevant for risk assessment resulting from the use of dimethoate (e.g. toxicity equivalence factors (TEFs)) for acute and chronic risk assessment to compare the toxicity of the metabolite with the toxicity of dimethoate; 

• A comprehensive list of authorised uses in the EU; 

• GAPs for the use of dimethoate and omethoate in third countries for which import tolerances are requested/required; 

• Supervised filed trials to estimate the residue concentrations of the parent compound and the relevant dimethoate metabolites in treated crops; 

• Processing studies to derive the residue concentrations of the parent compound and of relevant dimethoate metabolites in processed products; 

• Feeding studies to derive residue concentrations of dimethoate and omethoate in food of animal origin. 

 

Some of the information required, in particular toxicological data on the relevant metabolites, may have been submitted to the RMS with the supplementary dossier for the renewal of the approval under Regulation (EC) No 1107/2009. The RMS should be contacted to verify if the required information is already available. The toxicological information would be required to initiate a comprehensive MRL review, including the decision on the most appropriate residue definitions and the TEFs. Following agreement on the residue definitions, the remaining data (e.g. supervised field trials on crops with registered GAPs covering all components of the residue definitions) need to be assessed in detail. 

 

A risk management decision needs to be taken whether the current evidence on possible consumer risks related to dimethoate residues (including metabolites) requires other measures which would have an immediate effect.