UPTAKE AND DISTRIBUTION OF CARBAMAZEPINE AND METABOLITES IN DIVERSE ORGANS OF Jenynsia multidentata, CHANGES IN THE ACTIVITY OF ACETYLCHOLINESTERASE.

VALDÉS, MARÍA EUGENIA; BERTRAND, LIDWINA; BISTONI MA. DE LOS ANGELES; HUERTA, B.; RODRIGUEZ-MOZAZ, SARA; BARCELÓ, DAMIÀ; WUNDERLIN, DANIEL A.

Barcelona

Congreso; SETAC Europe 25th Annual Meeting; 2015

SETAC EUROPE

Pharmaceuticals are emerging contaminants ubiquitously found in watercourses, whose ecotoxicological and human risk is still under research. In the SuquíaRiver basin (Córdoba, Argentina), atenolol, carbamazepine anddiclofenac were the pharmaceuticals most frequently detecteddownstream the WWTP of Córdoba city. Jenynsia multidentata is awidespread native fish proposed as bioindicator in the basin. The goalsof this work were: 1) to optimize a methodology for the analysis ofpharmaceuticals in small organs of fish, 2) to analyze thebioconcentration and distribution of carbamazepine (CBZ) in organs ofJenynsia multidentata and 3) to measure changes in acetylcholinesterase(ACh) activity after exposure to CBZ, as a biomarker of neurotoxicalearly effects. An extraction methodology was optimized for the analysisof 20 pharmaceuticals in freeze-dried small amounts of fish organs (25mg dry weight of liver, intestine, muscle, gills and 10 mg dw of brain),by ultrasonication with methanol and solid phase extraction as cleanup1. Separation and detection were accomplished by UHPLC-MS/MSfollowing an already validated method. This method was applied toquantify CBZ and 2 metabolites (10,11-epoxyCBZ and 2-hydroxyCBZ)in organs of J. multidentata(total weight: 0.5 ± 0.2 g; standard length: 29± 2 mm) exposed to 100 μg/L CBZ in water for 48 h under laboratoryconditions. Matrix-matched calibration using internal standards wasapplied (linearity in the range 0,5-1 to 50 μg/L). Limits of detection rangewere 0.1-30 ng/g dw and recovery between 30-150%. Matrix effectswere noticeable, being ion suppression the most important one. Whennecessary, dilutions were made to diminish this effect. CBZbioconcentration was observed in the 5 organs of exposed fish (max.:701 ng/g wet weight in brain) as well as 2-hidroxiCBZ (max.: 107 ng/gww in liver).The active metabolite 10,11-epoxiCBZ was quantified ingills and muscle (max.: 60 ng/g ww). An enzymatic extraction protocolwas applied for the analysis of ACh activity by spectrophotometry inbrain and muscle of J. multidentata exposed48 h to 0.5, 10 and 100 μg/LCBZ in water. A significant ACh activation was observed in brain offish exposed at 10 μg/L CBZ. No differences were observed in musclesunder the tested conditions. Results demonstrate that CBS can be uptakeby fish from polluted water, metabolized and distributed in diversetissues, affecting ACh activity.