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It is essential to monitor organic pollutants to control contamination levels in environmental water bodies. In this respect, the development of new materials based on functionalised polymeric films for the measurement of toxic compounds is of interest. In this study, we prepare new films based on polymer cellulose triacetate modified with multi-walled carbon nanotubes for the monitoring of selected compounds: a fungicide (chlorpyrifos) and two emerging contaminants, the musk tonalide and the bactericide triclosan, which are used in the formulation of personal care products. The films, upon contact with water samples and following the principles of thin film microextraction, allow the determination of organic pollutants at low concentration levels. The contact time of the film with a predetermined volume of water is fixed at 60 min, and the compounds are eluted with a small volume (1 mL) of organic solvent for GC-MS analysis. Parameters such as repeatability for different films and detection limits are found to be satisfactory. Applying the method to river water demonstrates its suitability and, in the cases of chlorpyrifos and tonalide, the absence of a significant matrix effect.

A supported liquid membrane-hollow fiber system (HFSLM) has been developed to determine zinc speciation in aquatic environments. The liquid membrane consisted of an organic solution of bis-(2-ethylhexyl)phosphoric acid (D2EHPA) impregnated in the microporous of a polypropylene hollow fiber. The membrane contacted both the donor solution, that contained the metal and the stripping solution, placed in the lumen of the hollow fiber, where the metal was preconcentrated. Different parameters affecting the Zn2+ transport efficiency have been evaluated such as the composition of both the donor and stripping solutions as well as the membrane phase. Extraction and transport efficiencies of free Zn(II) higher than 90% were obtained with a liquid membrane consisting of a 0.1 M D2EHPA solution in dodecane and a 0.1 M HNO3 solution as the stripping phase. The developed HFSLM was used to study the effect of different ligands (EDTA and citric acid) in the donor phase of Zn(II) transport and to investigate the selectivity of the membrane towards Zn when other metals were also present. Finally, the HFSLM system was successfully applied to estimate the free Zn(II) concentrations in three water samples from a mining area. Moreover, the HFSLM system facilitates the analytical determination of trace Zn(II) levels allowing the achievement of enrichment factors of around 700 in the stripping phase Ministerio de Economía y Competitividad (Spain) through project CTM2016-78798-C2-2-P (AEI/FEDER/UE)