Last reviewed 4 Nov 2026 · 2 min read
1. Meaning
DefinitionSoil pollution
The presence in soil of chemicals or materials at levels that harm soil organisms, plants, animals or people, or that degrade the soil's functions — fertility, water filtering and support of life.
Soil is a sink for many pollutants: they can stay for decades, move into crops and food chains, or leach into groundwater.
2. Sources and pollutants
| Source | Pollutants |
|---|---|
| Agriculture | Excess fertilisers (nitrate, phosphate), pesticides (organochlorines, organophosphates), salt build-up from irrigation, cadmium in phosphate fertilisers |
| Industry | Heavy metals — lead, cadmium, chromium, mercury, arsenic, nickel, zinc; tannery chromium; dyes; fly ash |
| Mining and smelting | Metal-rich tailings, acid mine drainage |
| Municipal solid waste | Open dumping, landfill leachate, plastics |
| E-waste | Lead, cadmium, mercury, brominated flame retardants from informal recycling |
| Sewage and sludge | Pathogens, heavy metals, pharmaceuticals |
| Petroleum | Oil spills, leaking underground storage tanks |
| Biomedical and hazardous waste | Infectious and toxic materials |
| Atmospheric deposition | Acid rain, lead from old vehicle exhaust |