engleski

Method development for the assessment of bioaccumulation potential of pharmaceuticals in fish

Active pharmaceutical ingredients (API) represent a group of the most prominent categories of emerging environmental contaminants. However, a vast majority of the currently published studies are focused on their occurrence and fate in abiotic environmental matrices like water and sediments while the data on API concentrations in aquatic organisms are still comparatively rare. Consequently, the existing knowledge on API bioaccumulation and metabolic transformations in the aquatic organisms is still inadequate. The key prerequisite to study bioaccumulation behavior of pharmaceuticals in the aquatic environment is the availability of analytical methods suitable for the reliable determination of trace concentrations of API and their metabolites in complex biological matrices. In this work, a novel multiresidue LC- MS/MS method for quantitative measurement of trace levels of selected APIs and their metabolites in freshwater fish was developed. In order to develop a robust analytical protocol suitable for reliable determination of 44 analytes, characterized by rather wide-range of physicochemical characteristics, in difficult fish matrices, the sample preparation protocol was optimized in a number of model experiments, by examining different combinations of extraction and clean-up techniques. The method development was performed using homogenized muscle tissue of Squalius cephalus (Chub) spiked with target analytes at low ng/g levels. In order to enhance the analytical reliability in complex fish matrices, the method included extensive usage of isotopically labelled surrogate standards. Two different extraction techniques, ultrasonic extraction and pressurized solvent extraction, were compared using different solvent combinations, taking into account two key parameters: absolute recovery (including extract suppression) and reproducibility. At the optimized conditions for LC/MS analysis, a Synergy Polar HPLC column was selected for chromatographic separation, using water and methanol, both containing 0.1% formic acid (v/v), as eluting solvents. The selectivity of the method was assured by highly specific MRM detection, using the two most abundant precursor/product ion transitions for each analyte and surrogate. The developed analytical method was used to assess API concentrations in feral freshwater fish from the Sava River (Croatia).

biota ; pharmaceuticals ; bioaccumulation

nije evidentirano