New fast screening method for organochlorine pesticides in water by using solid-phase microextraction with fast gas chromatography and a pulsed-discharge electron capture detector

Abstract

A new fast screening method has been developed for the analysis of organochlorine pesticides in water that takes less than 10 min to perform and has detection limits of the order of 10 ng l^–1. Pesticide extraction was achieved by solid-phase microextraction and the separation was performed using a micro-bore (0.1 mm) capillary column. A laboratory-built cryotrap system was used to focus the analytes prior to introduction to the column and a pulsed-discharge electron capture detector enabled sensitive, selective measurements of the pesticide peaks to be made. The 100 µm polydimethylsilicone (PDMS) coated fibre gave better recoveries than the 30 or 7 µm film PDMS fibres and an inter-fibre study comparing three 100 µm film fibres showed good reproducibility. With extraction times of 2 min, the procedure was found to be linear over the range 0.01–1.2 ng ml^–1. The procedure was tested with a real river water sample.