Imidacloprid and clothianidin insecticides individual and mixture effects on fish Labeorohita plasma electrolytes and gill Na+/K+ ATPase activities.

Abstract

Neonicotinoids are a new class of insecticides that are widely used around the world owing to their efficacy and insect selectivity. Imidacloprid and clothianidin are major neonicotinoids which are frequently found in the aquatic environment, especially in streams. The present investigation evaluated the individual and combined toxicity of imidacloprid and clothianidin in the freshwater fish Labeorohita. The fish were intoxicated with imidacloprid (66.6 mg/L), clothianidin (30 mg/L) and their combination mixture (IMI: 33.3 and CLO: 15.0 mg/L) for 42 days. The plasma electrolytes such as Na⁺, K⁺andCl^- andgills Na⁺/K⁺ ATPase were evaluated. The plasma electrolytes (Na⁺, K⁺ andCl^-) and gill Na⁺/K⁺ ATPase activities were significantly inhibited throughout the exposure period. The maximum inhibition was noted on the 28^th day of intoxication and is more in the mixture than the individual.