Sequential solid phase extraction protocol followed by liquid chromatography atmospheric pressure chemical ionization mass spectrometry for the tracedetermination of non ionic polyethoxylated surfactants in tannery wastewaters

Automated solid-phase extraction (SPE) with C18 and styrene-divinylbenzene cartridges in series was used for the preconcentration of non ionic polyeth oxylated surfactants in tannery wastewater. Fractionated extracts were anal yzed by LC-MS using Atmospheric Pressure Chemical Ionization (APCI) in the Positive and Negative Ion modes. Recoveries for nonionic surfactants were a pproximately of 72, 90 and 80% for polyethylene glycols, nonylphenol and al cohol ethoxylates in the polar, aromatic and medium polarity fractions, res pectively. Data acquisition in the selected ion monitoring mode afforded li mits of quantification from 0.1 to 0.8 mu g/l for tridecylic polyethoxylate d alcohol and polyethoxylated glycol, respectively, in the complex tannery wastewaters. The tannery effluents investigated contained between 0.03 to 3 .0 mg/l of polyethylene glycol and nonylphenol polyethoxylate, respectively . (C) 1999 Elsevier Science Ltd. All rights reserved.