Multiresidue pesticide analysis to determine the influence of postharvest packinghouse handling on papaya residue levels

Abstract

The objective of this work was to adapt and validate a multiresidue method for pesticide analysis, to determine the influence of the current postharvest handling steps on the degradation of pesticide residues in papaya. 'THB' papaya of the Solo group were sampled at each postharvest handling step in the packinghouse. For the validation of the multiresidue analysis in papaya, the technique used for extraction was the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, with modifications. Pesticide quantification was carried out using an ultra-high performance liquid chromatograph coupled to a triple quadrupole mass spectrometer with electrospray ionization (UHPLC-MS/MS). Fruit were analyzed before and after the handling procedures and were evaluated after ripening. The used methodology was successfully validated to detect the azoxystrobin, carbendazim, carbofuran, difenoconazole, imazalil, imidacloprid, flutriafol, prochloraz, pyraclostrobin, tebuconazole, thiabendazole, and thiacloprid pesticides in papaya. Fruit washing reduces azoxystrobin and difenoconazole residue levels in 78 to 90% and in 47 to 90% on fruit surface, respectively. Although the postharvest handling steps are ineffective in reducing the levels of thiabendazole, if this fungicide is applied at the appropriate rate, the residue levels will remain below the limits permitted by law.