Modification of the existing maximum residue levels for difenoconazole in various crops

Combined Developmental Toxicity of the Pesticides Difenoconazole and Dimethomorph on Embryonic Zebrafish

Difenoconazole (DIF) and dimethomorph (DIM) are widely used pesticides frequently detected together in environmental samples, so the deleterious effects of combined exposure warrant detailed examination. In this study, the individual and combined effects of DIM and DIF on conventional developmental parameters (hatching rate, deformity rate, lethality) and gene expression were measured in embryonic zebrafish. Both DIF and DIM interfered with normal zebrafish embryo development, and the most sensitive toxicity index for both was 96 h post-fertilization (hpf) deformity rate (BMDL₁₀ values of 0.30 and 1.10 mg/L, respectively). The combination of DIF and DIM had mainly synergistic deleterious effects on 96 hpf deformity and mortality rates. Transcriptome analysis showed that these compounds markedly downregulated expression of mcm family genes, cdk1, and cdc20, thereby potentially disrupting DNA replication and cell cycle progression. Enhanced surveillance for this pesticide combination is recommended as simultaneous environmental exposure may be substantially more harmful than exposure to either compound alone.

Analysis of Multi-Pesticide Residues and Dietary Risk Assessment in Fresh Tomatoes (Lycopersicum esculentum) from Local Supermarkets of the Metropolitan Region, Chile

In recent years, the official authorities in Chile have reported transgressions in the maximum residue levels of pesticides in fresh vegetables. There is no official information about traceability, pesticide levels, and potential health risks. The aim of this study was to analyse pesticide residues and their corresponding dietary risk assessments in tomatoes from supermarkets in the Metropolitan Region. Pesticides were extracted using the Quick, Easy, Cheap, Effective, Rugged and Safe, QuEChERS method, and their concentrations were determined by using chromatography with HPLC-FL/UV and GC-MS/ECD/NPD, following the Analytical Quality Control and Method Validation Procedures for Pesticides Residues Analysis in Food and Feed, SANTE guide and ISO 17025:2017 standard. In addition, a dietary risk assessment was carried out by comparing Chilean data to international references. The results reported that 9% of the samples had pesticide residue levels above the maximum residue levels permitted in Chile. All the scenarios evaluated revealed the highest estimated daily intake and hazard quotients for methamidophos and chlorpyrifos. Both the active substances used were acetylcholinesterase inhibitors and were neurotoxic under chronic risk assessment. The results showed the highest chronic hazard index in the Chilean scenario for all age groups and genders. The evidence obtained revealed that methamidophos, methomyl, and chlorpyrifos should be restricted for their use in Chilean agriculture.

Modification of the existing maximum residue levels for difenoconazole in leafy brassica

In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant Syngenta Crop Protection AG submitted a request to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for the active substance difenoconazole in commodities belonging to the group of leafy brassica. The data submitted in support of the request were found to be sufficient to derive MRL proposals for leafy brassica. Adequate analytical methods for enforcement are available to control the residues of difenoconazole in plant matrices under consideration at the validated LOQ of 0.01 mg/kg and for difenoconazole and metabolite CGA205375 in animal matrices at the validated LOQ of 0.01 mg/kg for meat muscle, fat, liver, kidney and eggs and at the validated LOQ of 0.005 mg/kg for milk. Based on the risk assessment results, EFSA concluded that for the crops assessed in this application the short‐term intake of residues resulting from the use of difenoconazole according to the reported agricultural practices is unlikely to present a risk to consumer health. Long‐term consumer intake concerns cannot be excluded for the intended and existing difenoconazole uses as they are affected by uncertainties associated with the toxicity of metabolite CGA205375 and the lack of information on all existing difenoconazole uses in the EU. Overall, this risk assessment is considered provisional, pending the submission of confirmatory data on possible preferential metabolism/degradation of the four stereo isomers of difenoconazole in plants and has to be re‐considered when the missing data become available. Additionally, this assessment does not take into consideration triazole derivative metabolites (TDMs) which may be generated by several pesticides belonging to the group of triazole fungicides as this application was submitted before September 2019 which is the date of application of the new strategy endorsed by the risk managers for the assessment of TDMs.