Acute Toxicity Test of Two Pesticides Diazinon and Deltamethrin, on Swordtail Fish (Xiphophorus helleri)

Pesticides and chemicals used in agriculture may finally inter aquatic environment and accumulate in the food chain and may cause serious ecological and health problems. The aim of the present study was to investigate acute effects of diazinon and deltamethrin as potential dangerous agricultural chemicals to assess and compare mortality rates of these chemicals on Swordtail Fish (Xiphophorus helleri) in the form of LC . 50 Fish were exposed to different concentrations of diazinon and deltamethrin (between 0-64 ppm for diazinon and 0-8 ppm for deltamethrin) for 96 h in 120 L glass aquaria. Although the observed significant difference between acute toxicity of the two pesticides, a very low LC was obtained for deltamethrin (2.87 ppm) and diazinon 50-96h (14.3 ppm) indicates that deltamethrin and diazinon are highly toxic to X. helleri. Further studies are recommended to investigate the effects of these harmful chemicals on fish physiology and histology and their accumulation in fish tissues. Although these chemicals are thought to be less toxic in field conditions due to their adsorption to sediments, these data are useful when assessing potential ecosystem risks.