Surveillance of pesticide residues in fruits from Valencia during twenty months (2004/05)

The aim of this study was to investigate the pesticide residues in market fruits (oranges, tangerines, nectarines, peaches and khakis) from one Valencian Cooperative (Spain) and to conduct a monitoring of 32 organophosphorous, organonitrogen and organohalogenated pesticides and nine dithiocarbamate fungicides (DTCFs) usually applied on cultures of this area. Extracts were obtained by an official procedure for routine analysis based on ethyl acetate extraction. Residues of pesticides were determined by gas chromatography with nitrogen phosphorous detector (NPD), electron-capture detector (ECD) and mass spectrometry (MS) detectors. Mean recoveries obtained at fortification levels between 0.05 and 5 mg kg−1 were in range of 56–97% with relative standard deviations (RSDs) from 5% to 18%. The limits of quantification (LOQs) were in range of 0.1–140 μg kg−1 and lower than maximum residue limits (MRL) established by the Spanish legislation. 73% of the samples had no detectable residues. Of the contaminated samples, 13.8% exceeded the maximum residue limits (MRLs). Peaches and oranges showed the lowest contamination rates (13.9% and 21.3%, respectively). The contamination and violation rates were similar than the percentages recorded in previous monitoring studies in the same Community. Estimated daily intakes (EDIs) were calculated for these compounds in basis of European maximum residue limits (MRL) and residues found in the analysed samples and were compared with the acceptable daily intakes (ADIs).