Systematic Determination of Pesticide Residues in Citrus Fruits

Abstract

A systematic method for determination of 42 kinds of pesticides (organophosphorus, organonitrogen and pyrethroid pesticide) in citrus fruits was developed. The pesticides were extracted from the citrus fruits with acetone, and the extract was concentrated. After addition of ethyl acetate to the concentrated solution, both acid and basic compounds were removed. The ethyl acetate layer was then subjected to capillary GC with NPD detection after clean-up with a Sep-pak Florisil cartridge.
The recoveries of 42 pesticides added to lemon at 0.010-1.00μg/g were in the range of 59.2-100.0%. The detection limits were 0.01-0.2μg/g.