Quantification of Pyrethroid Insecticides at Sub-ppb Levels in Sediment Using Matrix-Dispersive Accelerated Solvent Extraction with Tandem SPE Cleanup

摘要

A rapid and sensitive analytical method was developed to quantify pyrethroid insecticide concentrations in sediment with method detection limits (MDL) at biologically relevant concentrations (sub-ppb levels). Pyrethroids were isolated from the sediment by matrix-dispersive accelerated solvent extraction, and the extracts cleaned with tandem solid phase cartridges packed with graphite carbon black and primary/secondary amine. Method detection limits, relative recoveries and precision were determined for two type I and six type II pyrethroids at several different concentrations using four different sediments. Additional fractionation with a Florisil column further improved method sensitivity. The method was successful at analyzing pyrethroids with MDLs of 0.11-0.85 ppb (dry sediment), and recoveries were 73.7-151.7% for sediment spiked with pyrethroids at 0.2 ppb dry weight.