Toxicity class

Toxicity class refers to a classification system for pesticides that has been created by a national or international government-related or -sponsored organization.

It addresses the acute toxicity of agents such as soil fumigants, fungicides, herbicides, insecticides, miticides, molluscicides, nematicides, or rodenticides.

Pesticides are regulated in the United States primarily by the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

Class I materials are estimated to be fatal to an adult human at a dose of less than 5 grams (less than a teaspoon).

Class III materials are estimated to be fatal to an adult human at some dose in excess of 30 grams.