Despite what many of us might think, no substance is inherently safe or unsafe. Any substance even the most innocuous can be harmful if you are exposed to too much of it. Pesticides are designed to be toxic to the target pest while being safe to the people that use these chemicals. However, accidents and misuse occur and they can cause illness or injury. Toxicity is the potential a chemical, such as a pesticide, has for causing harm.
Some pesticides have low human toxicity while others are extremely toxic.
The greater the quantity of a chemical you are exposed to, the greater the risk of injury. The effect of a given dose varies with the weight and age of the person. Therefore, an amount that is relatively harmless to an adult may hurt a small child. Route of absorption. The ways the body comes in contact with chemicals.