MICROWAVE EXTRACTION OF PHTHALATE-ESTERS FROM MARINE SEDIMENT AND SOIL

As part of an on-going ASEAN(+))-Canada Cooperative Programme on Marin e Science, microwave-assisted solvent extraction has been employed for the extraction of six phthalate esters from marine sediment and soil samples. Five of the six esters studied are among the United States En vironmental Protection Agency's list of top priority pollutants. The e ffects of extraction solvent, extraction temperature, duration of extr action and extraction volume on the mean recoveries of the six phthala te esters were quantitatively evaluated by means of an analysis of var iance, followed by testing the differences among the level means for e ach condition with least significant difference method. Microwave-assi sted solvent extraction allowed comparable or higher recoveries of the six phthalate esters (70.1-91.0 %) in comparison with conventional so xhlet (65.5-89.5 %) and sonication (64.6-88.6 %). The precision of res ults by microwave-assisted solvent extraction was improved significant ly compared to the conventional techniques. The microwave extraction s ystem has many advantages over the soxhlet and sonication extraction, e.g., no laborious clean-up procedure, lower usage of hazardous organi c solvent, and larger sample throughput. The technique has been employ ed for the analysis of native marine sediment and soil samples in Sing apore.