This study was designed to evaluate the acute toxicity of acetamiprid (neonicotinoid) and lambda-cyhalothrin (pyrethroid), individually and mixtures (Act-LCh mixture and Acer 35 EC®, 15 g/L of acetamiprid and 20 g/L of lambda-cyhalothrin) in African catfish juveniles (3.35 ± 0.75 g). The tests were conducted in the laboratory under semi-static conditions according to OECD Guideline 203. Mixture toxicity effects as a function of lethal concentrations were assessed using the additive index (AI) method. Acetamiprid with 96 h-LC₅₀ = 265.7 ppm can be considered to be nontoxic for this species. However, lambda-cyhalothrin was highly toxic to C. gariepinus with 96 h-LC₅₀ = 0.00083 ppm. Acer 35 EC^® was less toxic (96 h-LC₅₀ = 0.21 ppm) than the Act-LCh mixture (96 h-LC₅₀ = 0.043 ppm). Marked changes indicating nervous system damage were also recorded. An antagonistic effect was shown for lethal concentrations leading to 5 to 15% mortality in 96 hours (96 h-LC_5-15) while an additive effect was obtained for the 96 h-LC_20-50. The results indicate that ecological risk assessment of these molecules in aquatic environments should consider their contamination levels. Moreover, particular attention to behavior changes related to their neurotoxicity is recommended for additional monitoring of the negative effects of these insecticides.

这项研究旨在评估单独和混合使用的乙酰胺类（新烟碱）和lambda-氯氟氰菊酯（拟除虫菊酯）的急性毒性（Act-LCh混合物和Acer 35EC®，15 g / L的乙酰胺和20 g / L的lambda-氯氟氰菊酯）（3.35±0.75 g）。测试是根据OECD准则203在半静态条件下在实验室中进行的。使用加成指数（AI）方法评估混合物毒性效应与致死浓度的关系。96 h-LC ₅₀ = 265.7 ppm的乙酰胺对这种物质无毒。然而，高效氯氟氰菊酯是剧毒C.鲇与96小时-LC ₅₀ = 0.00083 ppm的。宏基35 EC ^®是毒性较低的（96小时-LC ₅₀＝ 0.21ppm）比Act-LCh混合物（96h-LC ₅₀＝0.043ppm ）。还记录了指示神经系统受损的明显变化。对于致死浓度，在96小时内（96 h-LC _5-15）导致5至15％的死亡率显示出拮抗作用，而对于96 h-LC _20-50则获得累加作用。结果表明，在水生环境中对这些分子的生态风险评估应考虑其污染水平。此外，建议特别注意与其神经毒性有关的行为变化，以进一步监测这些杀虫剂的负面影响。