Interactive Toxic Effects of Agrochemicals on Aquatic Organisms

Abstract : The effects of three common agrochemicals, lindane, methyl parathion and atrazine, on crustaceanDaphnia magna, algaSelenastrum capricornutumand marine bacteriumVibrio fischeriwere investigated in this study. Methyl parathion was the most toxic compound towards all three organisms, while lindane was more toxic toDaphnia magnaandVibrio fischerithan atrazine, and atrazine was more toxic toSelenastrum capricornutumthan lindane. Among the three aquatic organisms,Selenastrum capricornutumwas most sensitive in detecting lindane and atrazine toxicity, whileDaphnia magnawas most sensitive in detecting methyl parathion toxicity. The interactive effects of the pesticides were also investigated. The interactive effect between lindane and methyl parathion on survival ofDaphnia magnawas synergetic, while the ones between lindane and atrazine and between methyl parathion and atrazine were generally additive. The interactive effect of the three pesticides on the growth ofSelenastrum capricornutumwas antagonistic with few cases of addition, while the effect of all the three pairs of pesticides on algal growth was also antagonistic. The interactive effect of lindane and methyl parathion onVibrio fischeriwas additive.