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The aim of this research is to establish the processing factors of six pesticides durong the preparation of fresh-cut lettuce and to assess the risk of ingestion of pesticide residues associated with the consumption of the same. A field study was carried out on the dissipation of three insecticides (imidacloprid, tebufenozide, cypermethrin) and three fungicides (metalaxyl, tebuconazole, azoxystrobin) during treatment conditions simulating those used for commercial fresh-cut lettuce. A simultaneous residue analysis method is validated using QuEChERS extraction with acetonitrile and CG-MS and LC-MS/MS analysis. The residues detected after field application never exceed the established Maximum Residue Limits. The processing factors were generally less than 1 (between 0.34 for tebufenozide and 0.53 for imidacloprid), indicating that the process, as a whole, considerably reduces residue levels in processed lettuce compared to fresh lettuce. It is confirmed that cutting, followed by washing and drying, considerably reduces the residues. A matrix effect in the dialyzation of the pesticides is observed and the in vitro study of bioavailability establishes a low percentage of stomach absorption capacity (<15%). The EDI/ADI ratios found in all cases were well below their ADI values, and the dietary exposure assessed (EDI) in fresh-cut lettuce showed no concerns for consumer health.

An analytic procedure was developed for the determination of the fungicides ametoctradin, boscalid, cyazofamid, dimethomorph, fenhexamid, kresoxim-methyl, mepanipyrim, metrafenone, and pyraclostrobin in grape and wine. A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure was used for the extraction. Analysis of the extract was performed by LC/triple quadrupole-MS/MS. A Poroshell 120 EC-C18 column was used with a programmed gradient mobile phase consisting of (A) acetonitrile containing 0.1% formic acid and (B) water containing 0.1% formic acid and 2 mM ammonium formate. The acceptance criteria for the method were those proposed in the SANCO guide. The method was linear for the range of concentration studied (5-100 μg/L), and R2 values were higher than 0.998 and RSD values below 18%. Recovery was over 73.2% in grape and 76.7% in wines, and there was no case of more than 100% recovery. The recovery RSDs in reproducibility conditions were below 17.13% in grape and 15.6% in wines.