Suitability of hydrophilic-lipophilic balanced copolymer as solid-phase extraction material for acidic herbicides

A simple and rugged solid-phase extraction (SPE) method for the determinati on of acidic herbicides, including phenoxyacetic acids, which are considere d to be endocrine disrupters (EDs), was developed. Spiked tap-water and wel l-water samples were alkaline hydrolyzed with NaOH, followed by a simple SP E procedure using a hydrophilic-lipophilic balanced (HLB) copolymer. The hy drophilic character of a HLB copolymer allows packing a sufficient amount o f hydrophilic property to prevent the wettability problems encountered with ODS and polystyrene packings. High and reproducible recoveries were obtain ed for both tap-water and well-water samples at a 0.4 mu g/1 spike level. F or five replicate analyses using 75 mi of spiked water, the method detectio n limit (MDL) of UV-HPLC analysis was 0.04 similar to 0.18 mu g/1.