This study describes the extraction of CBs and OCs from water by conventional means using only a few millilitres of solvent. The parameters investigated were volume of n-hexane versus time of extraction. The results clearly show several alternatives to the analyst, i.e., smaller volume-longer time or larger volume-shorter time. Typically, good recoveries could be achieved with as little as 5 mL of n-hexane in a single step 10-minute extraction of a one-litre water sample, but more consistent results were obtained with environmental water with two successive extractions using 2 mL of solvent and a few drops of acetone to reduce emulsions. For instance, average recoveries of 83.29 and 87.75 were obtained for CBs and OCs. respectively, in a multi-residue analysis of environmental water comprising 22 components at the 0.01#x2013;0.25 ppb level. Thus, the microextraction approach looks very promising as an alternative to the lengthy and often more costly traditional liquid-liquid extraction approach for the analysis of CBs and OCs from environmental water. In fact recoveries are better for volatile analytes such as low molecular weight chlorobenzenes because the evaporation step is eliminated. Also, precision of the data for individual congeners is better.
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