The toxicity of a pesticide is its capacity or ability to cause injury or illness. The toxicity of a particular pesticide is determined by subjecting test animals to varying dosages of the active ingredient (a.i.) and each of its formulated products. The active ingredient is the chemical component in the pesticide product that controls the pest. The two types of toxicity are there - acute and chronic.
Acute toxicity of a pesticide is the ability of the chemical to cause injury to a person or animal from a single exposure, generally of short duration.
The chronic toxicity harmful effects that occur from small doses repeated over a period of time. Acute toxicity is measured as the amount or concentration of a toxicant— the a.i.—required to kill 50 percent of the animals in a test population. This measure is usually expressed as Lb50(lethal dose 50) or LC50 (lethal concentration 50). The lower the Lt)50 or LC50 of a pesticide product, the greater its toxicity to humans and animals.