Pesticides are chemicals that are designed to kill a variety of biological lifeforms that are undesirable in one way or another. The “cide” suffix comes from a Latin word meaning “killer.” Pesticides are designed to kill insects, weeds, or bacteria, but they can also harm humans.
Pesticides contain a variety of chemicals and are inherently toxic. In addition to the active ingredient which kills the intended pests, they also contain several other ingredients that are classified as “inert” because they do not kill the pest. However, even the inert ingredients can be harmful to humans.
Depending on the specific ingredients, pesticides can cause a variety of health effects. Even low levels can cause irritation to the eye, nose, and throat. Stronger chemicals or higher levels can lead to damage to the kidneys and central nervous system. There is also some evidence that pesticide use can increase the risk of cancer.
According to recent studies by the U.S. Environmental Protection Agency (EPA):
- 75% of U.S. households used at least one pesticide product indoors every year
- 80% of pesticide exposure occurs indoors
- Indoor air in most homes contains measurable levels of up to a dozen pesticides
Some pesticides are intended to be used indoors (for example disinfectants and some insecticides). But even those that are intended only for outdoor use (herbicides, strong insecticides, etc.) can enter homes when soil is tracked in on the bottom of shoes, when dust is blown through open windows or doors, or when the wind blows in pesticides as they are being sprayed.
There is still much that is not known about the health effects of pesticides, so it is important to limit their use as much as possible and take steps to minimize their presence, particularly inside our houses. Our next article will discuss in more depth ways to prevent overexposure to pesticides.