Análisis espacial de la concentración de metales en el camarón gris Crangon crangon (Linnaeus, 1758) en el Mar del Norte meridional

Abstract

APLICATION OF SOLID-PHASE MICROEXTRACTION TO ENVIRONMENTAL ANALYSIS The main objective of this thesis was to evaluate two recently developed extraction techniques, solid-phase microextraction (SPME) and stir bar sorptive extraction (SBSE) for the determination of several families of environmental contaminants in water samples. These extraction techniques were used combined to gas chromatography (GC) and high-performance liquid chromatography (HPLC) in order to establish analytical methods which can determine these pollutants in water samples from different origins. First, SPME was coupled to GC to determine different pesticides such as Irgarol 1051 or aldrin, and some phthalate esters. The parameters affecting SPME process were optimized and the developed method was applied to the determination of these compounds in water samples from marinas and coastal water, Ebro river water and mineral water. Other parameters affecting SPME process such as adding an internal standard to the sample to increase the precision of the method or the effect of storage time in the stability of analytes retained by the fiber were also evaluated. The combination of SPME to HPLC was also applied to determine phenols and some environmental estrogens in water samples. In this case, the commercial interface developed to couple these two techniques was used and a modification of the conventional design to connect SPME-HPLC interface to the liquid chromatograph was proposed to solve the distortion of peaks observed when the commercial interface is used. The parameters affecting the SPME process were optimized and the methods developed were applied to determine these contaminants in water samples from Ebro River and Tarragona wastewater treatment plant. SBSE, an extraction technique recently developed and based in SPME was applied combined with large volume injection in GC (LVI-GC) to determine pesticides considered endocrine disruptors in water samples. As in SPME, the parameters affecting the SBSE process were optimized and the method was applied to the determination of these compounds in samples from Ebro River. The combination of SBSE with LVI-GC proved to be a useful alternative when the thermal desorption unit is not available.