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A simple and sensitive method for the determination of 21 polyphenolic compounds in wastewater from olive oil production plants is proposed. The method involves a liquid-liquid microextraction (LLME) procedure with ethyl acetate followed by a silylation step. Identification and quantification have been performed by gas chromatography-mass spectrometry (GC-MS). MS measurements were carried out using selected ion monitoring mode (SIM). alpha-Naftol was used as internal standard. The proposed method was applied to the determination of these compounds in wastewater from an olive oil production factory in Jaén (Spain) at concentration levels ranging from 1.0 to 75.0mugml(-1) for each compound. The autodegradation process by own microbiota in samples collected in three different points of the factory was also studied. The method was validated by a recovery assay with spiked samples.

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An anodic stripping voltammetric determination of lead ions in laboratory prepared solutions is described utilizing a poly(vinylsulfonate)-doped polyaniline modified glassy carbon electrode. The experimental signals observed were similar to those of typical stripping methods and showed excellent linearity within the micromolar concentration range studied.The advent of stripping voltammetry has improved the performance of analytical voltammetry to a considerable extent. 1 The enhanced sensitivity and lower detection limits can be achieved in this technique by enrichment of the analyte prior to voltammetric determination. The common enrichment processes include reduction of metal ions through formation of metal films or amalgams, reductive or oxidative formation of sparingly soluble salts with or without reagent addition, and adsorptive accumulation of chelates or complexes onto the electrode surface. The universal working electrodes for stripping analysis are the stationary mercury electrodes, namely the hanging mercury drop electrode (HMDE) and the electrochemically generated mercury film electrode (MFE). In some cases, carbon-based electrodes as well as the noble platinum and gold metals are used when mercury electrodes pose some complications.Recently, there has been a growing interest in the area of chemically modified electrodes for trace metal analysis. 2 Prompted by environmental issues, these investigations are also aimed at the development of mercury-free electrodes for electroanalysis in which lead is of significant concern. 3 In this communication we report a totally mercury-free voltammetric stripping technique for the analysis of lead ions using a conducting polymer modified electrode.

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