Determination of pyrethroid insecticides in vegetables with liquid chromatography using detection by electrospray mass spectrometry

Liquid chromatography with electrospray mass spectrometry (LC-ES-MS) instrumentation equipped with a single quadrupole mass filter has been used to determine several pyrethroid insecticides (fenpropathrin, lambda-cykalothrin, deltamethrin, fenvalerate, permetkrin, taufluvalinate and bifenthrin). The applicability of the method to the determination of insecticides in spiked cucumber, green bean, tomato and aubergine was evaluated. Samples were extracted into dichloromethane without a clean-up step. Interferences due to the matrix effect were overcome using matrix matched standards. The limits of detection ranged from 4-8 ng mL(-1) (3 and 6 ng g(-1) in the vegetable samples), with relative standard deviations < 6.8%, using blank vegetable extract. Mean recoveries ranged from 80.1-109.8%.