A simple low-cost ultrasonic extraction procedure has been developed for determination of polar aromatic acids, polar phenols and nonpolar pesticides simultaneously in soil. This procedure was accomplished by in situ derivatization as well as elevated temperature, increased power and dispersing intimate contact of solvent with samples. Combined with GC/NCI/MS method, the sensitivity was improved remarkablely because of the enhanced electronegativity of derivatized products of herbicide and phenols as well as the intrinsic electronegativity of organochlorine. The method presented here showed that the modified ultrasonic extraction method can be a robust preparation methodology for both polar and nonpolar organic contaminants which can be applied to solid sample pre-treatment extensively.

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