Toxicity is the potential a substance has to poison humans, animals, or plants.
A wide range of toxicities exists among pesticides, and many can be deadly if encountered in the necessary amount. Small amounts of certain pesticides can cause damage to the human body. For example, insecticides are formulated to kill insects by attacking certain body systems, and they may attack that same system in a human. Heightened sensitivity is an allergic reaction on an area of skin. A rash may develop on any area of skin that contacts the chemical.