The soil is the default place where they end up much of the solid and liquid waste of any human activity. Soil contamination is the presence of chemical compounds made by man or other alteration to the natural soil environment. Everything that is not useful in any industrial, mining, urban, agricultural processing, etc. It is accumulated uncontrollably on the floor over the years. The chemicals can be detected in the soil range from petroleum hydrocarbons, solvents, pesticides and other heavy metals.
The use of chemical insecticides makes a soil contamination.
Agricultural activity has increased in recent decades due to population increase, requiring increased production to supply the entire population. This is mainly based on the payment of land to increase planting areas and conservation of existing as well as pest control, increased by insects that breed to have more food that attack.
These methods for controlling pests and insects are very aggressive and devastating the land, the use of nitrates, phosphates, etc. it will contaminate soil and this is because annually poured tons of fertilizers and pesticides. Water also suffer contamination by infiltration thereof into rivers or aquifers to be used by man.
New insecticides adapted to new insect pests are manufactured each year.
Chlorinated insecticides organs can be kept for over ten years in the soil without breaking down. It has been shown to be introduced into the food chain by concentrating in the fatty tissues of animals. There horticultural insecticides that are biodegradable and do not concentrate, but its toxic action mechanism is associated with the transmitter of nerve impulses in animals and people. Fungicides are used to combat fungi, their chemical compound is sulfur and copper. There are herbicides that destroy any plant life preventing their growth.
When used pesticides or herbicides increases the pollution in the water.
The effects on soil of these pollutants can be varied by time or weather conditions, accelerating or decreasing their solubility. But when the own damping capacity of nature is exceeded, a chemical time bomb does not produce immediate effects but may do so in the future is.