Abstract
Fingerling rainbow trout (S. gairdneri) were used to determine the lethal toxicity of Matacil 1.8 F and Matacil 1.8 D [insecticides] ready-to-use formulations. The 96-h LC50 were 21.3 mg/l for water-based Matacil 1.8 F, 29.1 mg/l for oil-based Matacil 1.8 F and 0.36 mg/l for Matacil 1.8 D. Aminocarb (4-dimethylamino-m-tolyl N-methylcarbamate) and MA (4-methylamino-m-tolyl N-methylcarbamate) were detected in fish tissue 96 h after exposure; > 50% of the total residue (aminocarb + MA) were the parent compound. The bioaccumulation ratio ranged from 1.70-3.32 at different concentrations of aminocarb. Aminocarb and MA were rapidly eliminated after the fish had been transfered to clean water; the total residue declined by > 90% in 72 h and became non-detectable in 96 h.