The European eel, Anguilla anguilla, is a common species. It has been known and present for millennia in Tunisia where it has always had a fish farming importance (Sanekli, 1981). Because of its position at the top of the food chain and its benthic way of life, the European eel is a species particularly exposed to organic or inorganic pollutants and therefore conducive to significant bioaccumulation. The pesticide application can lead to the dissipation of these compounds in the aquatic environments and subsequently to a very high risk of contamination of non-target species such fishes. Simazine is a synthetic herbicide of the triazine chemical family that inhibits photosynthesis of plants. This herbicide is capable of inducing physiological disturbances and histological changes in fish. The present study was conducted to determine the toxicity and effects of herbicide simazine commercial formulation on the biochemical parameters and oxidative stress biomarkers in European eel Anguilla Anguilla. Eels were exposed to ascending simazine concentrations: C=0µg/L [control], C1=0.3 µg/L, Group 1 (G1), C2=50µg/L Group 2 (G2) and C3=100µg/L Group 3 (G3)] during 96 hours.
For lipid content, we note, in the different organs studied, a decrease following simazine contamination compared to controls. The lowest protein level was recorded for G1 weakly exposed to simazine. Non enzymatic biomarkers are also influenced by contamination. Overall, there is an increase in the MDA content following contamination compared to controls especially for G1 in the liver, gill and kidney. The liver followed by the kidneys are the organs richest in AOPP whatever the concentration of simazine. Compared to the control, a significant increase (p<0.05) of AOPP is observed in kidney for G1. Decrease of NPSH is recorded in G3 compared to the control. We monitored the activity of catalase as enzymatic biomarkers. We found that the only significant variation was noted in gill with an increase (p<0.05) in catalase activity in G2 and G3 compared to G1. Finelly, for acetylcholinesterase activity, we note for gill and in G3 a significant decrease with regard to G2 (p<0.05).