title: Distribution of antidepressants and their metabolites in brook trout exposed to municipal wastewaters before and after ozone treatment--evidence of biological effects.
abstract: This study examined the tissues distribution of selected serotonin reuptake inhibitors (SSRIs) in brook trout exposed for 3 months to continuous flow-through primary-treated effluent before and after ozone treatment. A reliable analytical method was developed for the quantification of trace amounts of antidepressants in small tissue homogenate extracts. Levels of six antidepressants and four of their N-desmethyl metabolites were determined using liquid chromatography-tandem mass spectrometry. Significant amounts of the SSRIs were found in fish tissue-in decreasing order: liver>brain>muscle. Sertraline and its metabolite desmethylsertraline were the predominant substances observed in most tissues (0.04-10.3 ng g(-1)). However, less SSRIs (0.08-1.17 ng g(-1)) were bioaccumulated in the ozonated effluent. The early molecular effects of these SSRIs on the Na/K-dependent ATPase pump activity in brain synaptosomes where also investigated in vitro and in fish exposed to the municipal effluents. With respect to their potential biological effects, in vitro exposure to selected SSRIs induced a reduction of the brain Na/K-ATPase activity in synaptosomes in a dose-dependent manner. Results showed that Na/K-ATPase activity was readily inhibited by exposure to municipal effluent before and, to a lesser extent, after ozone treatment. Moreover, the Na/K-ATPase activity was significantly and negatively correlated with brain tissue concentrations of fluoxetine (r=-0.57; p<0.03), desmethylsertraline (r=-0.84; p<0.001), and sertraline (r=-0.82; p<0.001). The present study reveals that SSRIs are readily available in fish, biologically active and corroborates previous findings on the serotonergic properties of municipal effluents to aquatic organisms.
authors.affiliation: Environment Canada, Fluvial Ecosystem Research, Science and Technology Branch, 105 McGill Street, Montreal, Quebec, Canada H2Y 2E7.
authors.forename: André
authors.initials: A
authors.lastname: Lajeunesse
authors.forename: Christian
authors.initials: C
authors.lastname: Gagnon
authors.forename: François
authors.initials: F
authors.lastname: Gagné
authors.forename: Séverine
authors.initials: S
authors.lastname: Louis
authors.forename: Patrick
authors.initials: P
authors.lastname: Cejka
authors.forename: Sébastien
authors.initials: S
authors.lastname: Sauvé
mesh_terms: D000818:Animals; D000928:Antidepressive Agents / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D002853:Chromatography, Liquid; D010126:Ozone / Q000737:chemistry*; D017367:Selective Serotonin Reuptake Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D053719:Tandem Mass Spectrometry; D014337:Trout / Q000378:metabolism*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*
chemical_list: D000928:Antidepressive Agents; D010126:Ozone; D017367:Selective Serotonin Reuptake Inhibitors; D014874:Water Pollutants, Chemical