Soil pollution is mainly from pesticides, insectides, fertilizers, industrial waste etc. Fallout from nuclear explosions also pollutes the soil. Radioactive substances resulting from nuclear explosions penetrate the soil and water systems. Industrial waste and other pollutants such as iron, plastic, alluminiurn, concrete, lead, tin etc also cause soil pollution by disturbing the biological properties of the soil. In urban areas solid waste which may not be biodegradable also contributes to soil pollution.
In India soil pollution is mainly due to pollution concentration in urban areas and unplanned development of industries. It has been estimated that the urban population of India produces about 15 million tonnes of solid waste per annum causing pollution.
Soil pollution many a time results in agricultural pollution when it refers to liquid and solid waste from farming including run-off from the pesticides, fertilizers, animal carcasses etc. Broadly speaking agricultural pollution is caused by any kind of refuse produces as a result of agricultural operations. The following are the main types of agricultural refuse producing agricultural pollution:
1. Manure and other wastes from farms or
2. Slaughter house wastes.
3. Fertilizer run-off from crop land.
4. Harvest wastes.
5. Pesticides that escape in the atmosphere or into the water supply.
6. Salt and slit drained from irrigated land or eroded land.
In addition to the above, rural domestic waste, dead bodies of animals, food processing waste also cause soil pollution.