Neurotoxicological Effects of Municipal Effluents in Fathead Minnow Pimephale Promelas

Abstract

Municipal effluents are known to be able of disrupting neuro-endocrine signaling pathways in oviparous organisms. The purpose of this study was to examine the neurotoxicity of a chemically-treated municipal effluent to adult fathead minnow (Pimephales promelas) after 21 days. Brain somatic index and lipid peroxidation (LPO), monoamine oxidase (MAO) and acetylcholinesterase (AChE) levels were determined in both male and female fish. The estrogenicity of the municipal effluent was confirmed by measuring vitellogenin production and energy expenses in the liver. Brain MAO and AChE activities increased at low effluent concentrations and decreased at higher concentrations (>10% v/v). The data suggest that males expend more metabolic energy than females and was related to vitellogenin, and that brain activity is impaired in both sexes in the presence of the effluent. In conclusion, exposure to municipal effluents could produce biochemical changes in the central nervous system in fish.