Solid-phase microextraction and gas chromatography–mass spectrometry for determining chlorophenols from landfill leaches and soil

Abstract

This work evaluates solid-phase microextraction coupled with GC–MS (electron impact ionization and negative chemical ionization) to determine chlorophenols in landfill leaches and soil. A polyacrylate coated fiber is used to investigate the optimal experimental procedures, which include adsorption time, pH, salt effect, desorption time, temperature and the depth of the fiber in the injector. Detection limits are determined to be in low ng/l range and better than those obtained by US Environmental Protection Agency methods using a conventional extraction technique for chlorophenols in water. According to the analytical validations, the linearity of the absorption ranges from 0.1–100 μg/l with R.S.D.s below 9%. In addition, the feasibility of applying the proposed method to determine chlorophenols in real samples is examined by analyzing landfill leachate samples and soil samples contaminated with pentachlorophenol. All the studied chlorophenols are determined in the soil contaminated samples. Moreover, the pentachlorophenol detected in the landfill leachate is estimated in the level of 21.6 μg/l with an internal standard method. The quantities of the other studied chlorophenols are at the level of 0.1 μg/l. The effects of humic acids and a surfactant on the extraction of chlorophenols in the landfill leachate have been studied.