Acute toxicity of the agricultural chemicals endosulfan and copper sulfate to a freshwater shrimp, Palaemonetes paludosus

The toxicity of endosulfan, a restricted use pesticida, and copper sulfate, an anti-algal agent, ranks among the highest in all insecticidas. Both chemicals, used in agricultura fields of southern Florida, are known to be highly toxic to aquatic invertebrates. Since Palaemonetes pugio, an extensively studied brackish water shrimp species, has proven to be excellent for toxicological analysis, a closely related freshwater shrimp species, Palaemonetes paludosus, was used as the test species in this study to determine the toxicity of endosulfan and copper sulfate in freshwater. A series of static renewal 96 h bioassays (renewed every 24 h) performed on juvenile P. paludosus resulted in the 96 h lethal concentration (LC50) estimates of 0.24 mug/L (0.24 ppb) for endosulfan and 0.79 mg/L (0.79 ppm) for copper sulfate. The results of this study, when compared to other studies, indicate that P. paludosus is more sensitive to endosulfan and copper sulfate than other similar aquatic invertebrate species and is therefore an excellent toxicological indicator.