Residue levels of ethoxyquin, imazalil, and iprodione in pears under cold-storage conditions

A gas chromatographic method is presented for the simultaneous determinatio n of the antiscald ethoxyquin and the fungicides imazalil and iprodione in peel and pulp of Blanquilla pears. Fruits were cold-stored in commercial ch ambers in normal atmosphere and in controlled atmosphere with low oxygen co ntent (oxygen and carbon dioxide were held at 2.5% and 1.5%, respectively). The method uses gas-liquid chromatography (GLC) with an alkaline flame ion ization detector (detector of N-P, NPD) and allows the detection of the men tioned compounds to minimum levels of 0.08-0.12 mg/kg in fresh fruit. With this system the evolution of residues in fruit was monitored throughout the period of cold storage. In the surveys carried out the residue levels of t hese compounds were found to be below the limits allowed by the legislation of European Union. For the three studied products residues in pulp are low er and disappear more quickly than in peel.