Monitoring organochlorine pesticides from landfill leachates by gas chromatography-electron-capture detection after solid-phase microextraction.

Landfill leachates contain significant amounts of organic carbon, nitrogen and heavy metals as well as other specific trace organic compounds like organochlorine pesticides. In this study a simple and reliable methodology was improved to detect organochlorine pesticides in leachate samples by using a previous solid-phase microextraction procedure [with a 100 microm poly(dimethylsiloxane) fiber] and chromatographic analysis by GC-electron-capture detection. The extraction time, temperature, ionic strength of the solution and sampling of the headspace were the parameters studied. Reproducibility achieved values below 20% RSD, and standard addition was used for pesticides confirmation.