Grădilă, MargaMincea, CarmenZaharia, Roxana2026-06-092026-06-0920251454-7406https://repository.iuls.ro/handle/20.500.12811/6578This study investigates the acute toxicity of cypermethrin and alpha-cypermethrin-based insecticides on cyprinid fish species. A 96-hour static non-renewal bioassay was conducted in the Ecotoxicology Laboratory of R.D.I.P.P. Bucharest. Juveniles of common carp (Cyprinus carpio) and Prussian carp (Carassius gibelio) were exposed to a range of insecticide concentrations. Acute toxicity data were analyzed using probit analysis, and 96-hour LC50 values (Mean Lethal Concentration) as well as the NOEC (No Observed Effect Concentration) were determined. Exposure to cypermethrin and alpha-cypermethrin induced behavioral and anatomical changes, including respiratory distress, loss of balance, reduced response to tactile stimuli, and abnormal swimming patterns, which intensified with increasing concentration and exposure duration. Among the tested species, common carp juveniles were the most sensitive, highlighting species-specific differences in susceptibility to these insecticides.EnglishAttribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)http://creativecommons.org/licenses/by-nc-sa/4.0/cyprinid fishacute toxicitycypermethrinalpha-cypermethrinbehavioral responsesArticle2393-4603https://doi.org/10.61900/SPJVS.2025.04.04