Effects of atrazine on the gill cells and ionic balance in a neotropical fish, Prochilodus lineatus

► We investigate the gills of a neotropical fish after atrazine exposure. ► Atrazine exposure inhibited the carbonic anhydrase activity. ► Na+/Cl− ratio did not change after atrazine exposure. ► Atrazine did not change Na+/K + -ATPase activity. ► Morphological gill cells responses maintained ionic homeostase.