Acute toxicity test of two pesticides diazinon and deltamethrin on spirlin (Alburnoides bipunctatus) larvae and fingerling

The present research was performed to determine and compare acute toxicity of diazinon and deltamethrin to spirlin larvae and fingerling. Diazinon and deltamethrin are common useful agricultural pesticides. LC50 of 24, 48, 72 and 96 h was attained by probit analysis software SPSS Version 16. Fish samples (21 fish in each test group) were exposed to different concentrations of diazinon and deltamethrin (diazinon: for fingerling between 1 to 20 ppm and larvae 0.25 to 2 ppm; deltamethrin: for fingerling between 0.01 to 0.2 ppm and larvae 0.0025 to 0.02 ppm) for 96 h and mortality were recorded. The LC50 96 h of diazinon for fingerlings and larvae were 7.88 and 0.69, respectively. The LC50 96 h of deltamethrin for fingerlings and larvae were 0.27 and 0.006 ppm, respectively. According to the results, larvae are more sensitive than fingerlings. In the present study, LC50 values indicated that deltamethrin is more toxic than diazinon to this species. Key words: Diazinon, deltamethrin, lethal toxicity, Alburnoides bipunctatus.