Micelle-mediated extractions using nonionic surfactant mixtures and HPLC-UV to determine endocrine-disrupting phenols in seawaters

An environmentally friendly method to extract endocrine-disrupting phenols (EDPs) from seawaters was realized using nonionic surfactant mixtures and micelle-mediated extractions. The preconcentration step was achieved directly in the seawater matrix, and was followed by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection without any clean-up steps to remove the surfactant mixture prior to injection. Various nonionic surfactant mixtures were used, and polyoxyethylene-10-laurylether (POLE) with polyoxyethylene-4-laurylether (Brij 30) was found to be the best to work with. Method optimization involved maximizing the preconcentration factor using the studied mixtures. The proposed method gave extraction recoveries ranging from 83.3 to 114.4% for an EDP spiking level of 46.7 mu g L-1, and from 63.4 to 112.4% for a spiking level of 4.7 mu g L-1 for EDPs studied in real seawater matrices, with relative standard deviations of < 12.1%. The detection limits of the method varied from 0.18 mu g L-1 for bisphenol A (BPA) to 1.17 mu g L-1 for 4-cumylphenol (4-CP). The method was applied to seawaters from the Canary Islands with successful results.