Soil Pollution

Definition:

Soil contamination or soil pollution is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment.

Soil is the thin layer of organic and inorganic materials that covers the Earth's rocky surface. The organic portion is derived from the decayed remains of plants and animals and the inorganic portion is made up of rock fragments; it was formed over thousands of years by physical and chemical weathering of bedrock. Productive soils are necessary for agriculture to supply the world with sufficient food.

Causes of Soil Pollution

There are many different ways that soil can become polluted, such as:

- Seepage from a landfill

- Discharge of industrial waste into the soil

- Percolation of contaminated water into the soil

- Rupture of underground storage tanks

- Excess application of pesticides, herbicides or fertilizer

The most common chemicals involved in causing soil pollution are:

- Petroleum hydrocarbons

- Heavy metals

- Pesticides