ASSESSMENT OF BIOCHEMICAL MARKERS AND BEHAVIOR RESPONSE OF NON-TARGET FRESHWATER TELEOST GAMBUSIA AFFINIS TO CARBOFURAN TOXICITY

Abstract

The objective of this study is to evaluate the toxicity of a carbamate pesticide, carbofuran, on a non-target species Gambusia affinis females. Fish were exposed for 15 and 40 days to two concentrations 0.191 and 0.255 mg/L corresponding respectively ¼ and 1/3 of the LC50) of carbofuran. After parturition, the frequency of malformations in offspring of treated females was evaluated. In addition, we studied the effect of acute toxicity of the carbofuran at 2, 4 and 6 hours on swimming activity, and on brain AChE response. A significant increase in enzymatic activity, and Malondialdehyde (MDA) concentration, along with decreased the activity of acetylcholinesterase (AchE), reduced glutathione (GSH) and total lipid contents in a time-and dose-dependent manner was observed in carbofuran group compared to controls. Acute exposure of Gambusia to carbofuran induced a decrease in swimming activity. This behavioral effect was significantly correlated with the decrease in the brain's AChE activity. Exposure of females to relatively low doses of carbofuran also led to a marked increase in the level of larvae skeletal alterations. Hence, the results proved that females strongly accumulate this pesticide during the reproductive cycle, and thus its effect can be transmissible to their offspring.