The tables provided give toxicity information for many of the common pesticides used in and near aquatic ecosystems. Acute effects are those that occur rapidly in animals following a single dose or single exposure to a chemical.
Death is the acute effect most commonly used in toxicity testing.
The acute toxicity of chemicals toxic to aquatic animals usually is reported as a LC50 value. The more toxic the pesticide, the lower its LC50 value will be. The toxicity of pesticides to aquatic animals is influenced by many factors. These include the species, age, sex, and condition of an animal, water temperature, and the pesticide formulation. As a result, several LC50 values can exist for the same chemical.