LAUSR

Abstract Loquat in Lebanon is subjected to sprays by a variety of unregistered pesticides, as is the case with minor crops in many parts of the world, to protect it from pests mainly scab. This malpractice would raise consumer's health safety issues related to pesticides residues that could be avoided if the pesticides industry worldwide is not reluctant in investing in the registration of minor crops pesticides. Penconazole is registered as a fungicide against scab on apples and pears in Lebanon without prior supervised field trials, but it is not registered on loquat. The aims of this study are to screen and quantify the range of pesticide residues in 128 loquat samples gathered from Lebanese market between 2017 and 2019, study the dissipation behavior of penconazole on apple and loquat in the field, confirm the critical good agricultural practices (cGAP) of penconazole on apples and propose a pre-harvest interval (PHI) for penconazole on Loquat in Lebanon. The samples were analyzed using a validated MRM method on apple with GC-MS/MS and LC-MS/MS determination. A total of 51 samples were irregular in terms of the pesticides residues found, with, residues of unauthorized pesticides detected on 48 samples. The most frequently encountered unauthorized pesticides banned in Lebanon were: cypermethrin (10.9%), dimethoate (6.25%), methomyl (6.25%), carbendazim (3.1%), and thiametoxam (2.3%). Penconazole dissipated following a first order kinetic dissipation model on apple and loquat. The half-life calculated on apple and loquat were 8.56 days and 9.49 days, respectively. A PHI = 14 days can be proposed for loquat with a MRL of 0.07 mg/kg without any food safety issues raised with the same cGAP practiced on apple.