Investigation of Acute Toxicity of Two Pesticides Diazinon and Deltamethrin, on Blue Gourami, Trichogaster trichopterus (Pallus)

2 Abstract: There is a growing concern over aquatic pollution because of its detrimental effects on biological life including human beings. The goal of the present study was to determine the acute toxicity of diazinon and deltamethrin as potential dangerous organic pesticides to assess mortality effects of these chemicals to the blue gourami, Trichogaster trichopterus in the form of LC50. Fish samples (7 fish in each test group) were exposed to different concentrations of diazinon and deltamethrin (between0-50ppm for diazinon and 0-0.40ppm for deltamethrin) for 96 h in 120 l glass aquaria. The very low LC50s obtained for deltamethrin (0.223 ± 0.07ppm) and diazinon (14.5 ± 0.91ppm) indicate that deltamethrin and diazinon are highly toxic to Trichogaster trichopterus. Further researches are recommended to study the processes by which these chemicals affect physiology and histology of fish and their accumulation in fish tissues.