Bioaccumulation of pharmaceuticals in fish of Suquía River basin (Córdoba, Argentina)

M. E. VALDES; BISTONI M. A.; WUNDERLIN D.A.; HUERTA B.; RODRIGUEZ-MOZAZ S.; BARCELO D.

Barcelona

Workshop; LC/MS/MS WORKSHOP ON ENVIRONMENTAL APPLICATIONS AND FOOD SAFETY; 2014

CSIC, ICRA, IDAEA

Pharmaceuticals are a class of emerging environmental contaminants ubiquitously found in watercourses, particularly those receiving inputs from wastewater treatment plants (WWTP). The occurrence of some commonly prescribed pharmaceuticals in the Suquía River basin (Córdoba, Argentina) has recently been reported (Valdés et al., 2014). Among 15 compounds analyzed, atenolol, carbamazepine and diclofenac were the most frequently detected in water samples downstream the WWTP of Córdoba city (reaching sub μg/L levels). The objective of this work was to evaluate the presence of pharmaceuticals in fish samples of Gambusia affinis and Jenynsia multidentata collected at the same sampling points (located at 35 and 70 km downstream the WWTP), using the analytical method developed by Huerta et al., 2013. Water samples were analyzed through solid phase extraction (SPE) using polymeric reverse cartridges (Strata-X?, 500 mg/6 mL, Phenomenex, USA) and high performance liquid chromatography coupled to high resolution mass spectrometry with electrospray ionization source (HPLC?qTOF, Agilent?Bruker Daltonics, USA). Freeze-dried fish homogenate samples (pool: 10 individuals) were extracted by pressurized liquid extraction (ASE 350, Thermo Scientific Dionex, USA), purified by gel permeation chromatography (HPLC-DAD, Agilent 1260 infinity, USA) and analyzed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry with electrospray ionization source (UHPLC- QTRAP hybrid triple quadrupole-linear ion trap mass spectrometer, Applied Biosystems, USA). Field-derived bioaccumulation factors were calculated as the ratio between fish concentration (μg/kg wet weight) and water concentration (μg/L). All 20 pharmaceuticals analyzed in fish were detected at least once in samples of G. affinis and J. multidentata at the 2 sampling points monitored. In agreement with water concentrations, higher pharmaceutical concentrations were found at the sampling point nearest to the WWTP in G. affinis. Moreover, higher amounts were found during the dry season in this species. Comparing both species, accumulation was similar during the wet season. However in the dry season differences became noticeable, as G. affinis (an introduced species, more abundant in polluted sites) accumulated a higher number of compounds and at higher concentration than J. multidentata (a native species with similar habits). Calculated field-derived bioaccumulation factors (BAF) for atenolol, carbamazepine and diclofenac were less than 1000 for both fish species. Atenolol was the most frequently accumulated, and exhibited higher BAFs during the wet season. Propanolol, a compound that was not detected in water samples, was found in both species. Even though a low potential of bioconcentration for pharmaceuticals in these fish would be expected from BAFs calculated, we should take into account that fish are continuously exposed to a mixture of pharmaceutical compounds, and a higher number of them might also be bioaccumulated, which could result in a worse ecotoxicological scenario for the biota.