PARENT SESSION

1H c (1) - Pharmaceuticals
Hall 6
1:45 PM - 3:30 PM, Wednesday, 30 April 2003
Chair: Tolls, J.¹, ¹
Co-chair: Kümmerer, K.², ²

(WE6/14) In vitro cytoxicity and sublethal effects of nine pharmaceuticals on fish hepatocytes.

Laville, Nathalie¹, Aït-Aïssa, Sélim¹, Porcher, Jean-Marc¹, Casellas, Claude², ¹ INERIS, Verneuil-en-Halatte, Oise, France² DSESP, Montpellier, Herault, France

ABSTRACT- Pharmaceuticals are found in the aquatic environment but their potential effects on non-target species remain unknown. In the framework of the French National Program for Research in Ecotoxicology(PNETOX2-ENIMED) we proposed to assess the in vitro cytotoxicity of nine pharmaceuticals on primary cultures of rainbow trout hepatocytes (TH) and PLHC-1 cell line using MTT test. Sublethal effects were evaluated by measuring CYP1A activity (EROD assay) and production of reactive oxygen species(DCFH assay). The pharmaceuticals tested were clofibrate (CF), fenofibrate (FF), carbamazepine (CBZ), fluoxetine (FX), diclofenac (DiCF), propranolol (POH), sulfamethoxazole (SFX), amoxicillin (AMX) and gadolinium chloride (GdCl3). All substances were cytotoxic except AMX at concentration up to 500 M. The calculated MTT EC50 values ranged from 2M (CF) to 261 M (GdCl3) in PLHC-1, and from 50 M (FF) to 550 M (CBZ) in TH. The three most cytotoxic substances were potential oxidative stress inducers and belonged to the peroxisome proliferating agents (CF, FF) or to the antidepressant class (FX). Moreover, FF, CF, DiCF and CBZ inhibited specifically the basal EROD activity in TH cells at clearly sublethal concentrations, suggesting the involvement of specific mechanisms. None of the tested drugs induced the EROD activity in PLHC-1 cells. This in vitro screening is a first step in the assessment of the pharmaceuticals' impact on non-target species. Interaction of drugs with xenobiotic detoxification pathways is demonstrated in fish and should be considered in ecotoxicological assessment of pharmaceuticals in a multipollution context.

Key words: fish cells, pharmaceuticals, toxicity, EROD