Effects of Some Pesticides on Tilapia nilotica and Daphnia magna Life

Application of pesticides creates hazards to the aquatic organisms. This study aimed to determined influence of bromacil, thiabendazole, malathion and mixtures of it on Tilapia nilotica (fish) and D magna . Effects included determination of mortality rate, losing sensation and behavior change (jump attempts) of fish and mortality rate for D. magna using concentration range from 0-6 mg/l. Normal growth of fish and D. Magana was observed under suitable laboratory conditions. The most toxic compound to D. magna was malathion, has an EC 50 (Effective concentration that affect 50% of experimental animal) value of 0.43 (mg/l) compared to that of bromacil 0.59 (mg/l). Mixture of bromacil and malathion was less toxic than separately and have larger EC 50 value 0.64 in toxic unit (TU) indicating potential antagonistic effect. Moreover, thiabendazole was more effective to fish than malathion. Relative toxicity (RT) indicates that thiabendazole has a lower value (0.276) than malathion indicating higher toxicity of thiabendazole. Furthermore, fish and D. magna were sensitive to low concentrations. These data indicate potent threats to aquatic organisms.