The Reach of Soil Pollution

Eutrophication

• Soil pollution that starts on farms and in backyard vegetable gardens can have a devastating impact on entire ecosystems. Most organic and inorganic fertilizers contain high levels of nitrogen and phosphorus, both of which are required for plant growth. Improper application of fertilizer can create high levels of waste nutrients in the soil.

  After leaching into the groundwater or being swept away in runoff, these excess nutrients often end up in lakes and ponds where, in a process called eutrophication, they create an environment perfect for algae. Algae grows out of control, resulting in algae blooms that cover the surface of the water and keep sunlight from reaching plants and animals below. Prolonged eutrophication can result in the death of the lake or pond ecosystem, followed by a conversion into wetlands and a gradual disappearance of the water.

Long-Term Health Risks

• When individuals -- especially children -- are exposed to soil polluted with contaminants like lead and mercury, the effects can stay with them for the rest of their lives. Lead dust can make its way into the soil from lead paint used in the home, or it can be carried by the wind into an area previously thought to be lead-free. Small particles can travel easily, and when children play in the dirt or ingest the particles, they can develop long-term health problems.

  Permanent effects from soil pollutants like lead can include slowed growth and continued small stature, along with other impairments such as damage to the structures of the nervous system, learning disabilities, hearing difficulties and chronic headaches. Even nitrogen leached into water through soil can result in illness in children and the elderly.

Spread of Bacteria

• Manure can be applied on a large or small scale as an organic fertilizer, but when it is produced by unhealthy cows the result can be a bacterial contamination of the soil. E. coli, commonly found in both manure and sewage, can leach into the groundwater and be deposited in the soil, where it is then transferred to humans -- typically children.

  Excessive application of fertilizers can also cause numerous strains of bacteria to multiply. The nitrates that are found in many commercial fertilizers aid in the reproductive cycle of the bacteria that causes cholera; when these nitrates sink into the soil and are collected by runoff, they can be deposited in areas where people not only rely on coastal waters for drinking and bathing, but where cholera bacteria are encouraged to multiply.

Contaminated Food

• On a large or small scale, soil pollution can extend to the food crops that are grown in the soil. Many pollutants such as ammonia can be absorbed into plants and in turn ingested by those who consume the harvest.

  Effects can range from small-scale -- a family eating contaminated food from their backyard garden -- to large-scale, with consumers purchasing commercially grown vegetables created in unhealthy agricultural settings.