Fact Sheet – Pesticides
Est Population At Risk At Identified Sites: 3.4 Million People*
Est Global Impact: 5 to 8 Million People*
What Are Pesticides?
Pesticides are those substances, often chemical in nature, that are used with the intent to repel or eliminate species that have an adverse affect on agricultural or horticultural production. Pesticides are also used to fight tropical diseases like malaria. This class of pollutants falls under the umbrella of agrochemicals or agrotoxins, and was initially developed to improve agricultural output, enhance crop growth, and repel or eliminate pests that hinder crop yields.
What Are Pesticides Used For?
The term pesticide encompasses a variety of compounds used in agriculture. A “pesticide” can be classified as an insecticide, herbicide, fungicide, nematocide, and molluscicide. Pesticides work by interfering with essential biological mechanisms of their target species, primarily through actions such as paralyzing an insect’s nervous system. However, since these biological mechanisms are not specific to one species, these chemicals can harm other organisms, including humans.
How Are Pesticides Released Into The Environment?
Pesticides enter and pollute the environment primarily through their direct application in agricultural fields. A significant percentage of the millions of tons of pesticides used each year is washed away by rainfall into nearby surface waters and groundwater. Pesticides can also be released through improper or abandoned storage facilities. This is a particular problem in low- and middle-income countries.
How Do Pesticides Reach Humans?
People are commonly exposed to pesticides through occupational inhalation and ingestion of contaminated food and water. Many commonly used pesticides are classified as Persistent Organic Pollutants (POPs), which do not easily biodegrade and can bioaccumulate in human and animal tissue. Today, the use of POPs chemicals is forbidden under the Stockholm Convention.
What Health Risks Can Pesticides Cause?
Health effects from pesticides are difficult to generalize because of the varied nature of the chemicals in this category. Certain insecticides, such as the organochlorine lindane, are highly persistent in the environment and are believed to affect the human nervous system. Various types of pesticides have been linked to skin irritation, convulsions, headaches, loss of vision, respiratory difficulties, fertility and neurological problems, cancers, and in extreme cases, death. The use of certain insecticides is associated with cancers of the prostate, pancreas, liver, and other organs.
*Population estimates are preliminary and based on an ongoing global assessment of polluted sites.
