Ultra trace analysis of 17 organochlorine pesticides in water samples from the Arctic based on the combination of solid-phase extraction and headspace solid-phase microextraction-gas chromatography-electron-capture detector

Solid-phase extraction (SPE) was combined with headspace solid-phase microextraction (HS-SPME) for the highly effective enrichment of 17 ultra trace organochlorme pesticides in water samples The [at-get compounds were successfully transferred from water samples to a gas chromatography capillary column by means of four consecutive steps, namely SPE, solvent conversion. I IS-SPME, and thermal desorption of the SPME fiber Parameters. including elution volume and breakthrough volume in the SPE step, temperature in the solvent conversion step. and fiber type. ionic strength, extraction temperature e. extraction time, and phi in the SPME step were optimized to Improve the pet of the method through either single factor comparative experiment or the orthogonal experimental design approach After optimization. the method gave high sensitivity with a method detection limit ranging from 0 0018 to 0027 ng L-1. good repeatability with a relative standard deviation less than 20% (IT =4) and acceptable recovery with a value mostly exceeding 60% External standard calibration was employed for the quantification, and a wide linear range (from 00010 to 60ng mL(-1)) with R-2 values ranging from 09988 to 09999 were observed In the end. the method was successfully applied to the Arctic samples. and the results showed that, among all the organochlorine pesticides, hexachlorocyclohexanes (HCHs) were the most predominant in the Arctic SLIT face water body with SLIM of their concentrations ranging from 0 262 to 3 156 ng L-1 (C) 2009 Elsevier B V All rights reserved