Soil pollution was brought to public attention in 1978 by the Love Canal disaster. Soil pollution is defined as changes to the physical, chemical, and biological properties of soil caused by human activity that degrade soil quality. Natural causes of soil pollution include landslides and hurricanes, while man-made causes include urbanization, industrial and agricultural wastes, mining, domestic wastes, and radioactive wastes. The disposal of industrial wastes on fertile lands degrades soil quality, while urban wastes can slowly poison the soil and damage its fertility. Radioactive elements in polluted soil can enter the food chain through plants.