Soil Contaminants and Remediation Techniques for Urban Soils
It has been found that soils in urban areas are contaminated with higher levels of heavy metals than rural areas. One consequence of this contamination is the potential health risk from consumption of home-grown vegetables and fruit in urban back yard environments. Inhalation risks from contaminated dusts generated while gardening is also a concern. Therefore, heavy metal contamination in urban soils is an environmental problem that needs an environmentally safe and economically feasible solution.
In particular, urban environments often have an increased median level of lead in soil (greater than 400 mg lead/kg) due to higher concentration of industries, age of and automobile traffic. Lead is deposited in soil from anthropogenic sources such as lead-based paint, automobile emissions (prior to the banning of leaded gasoline in 1986), and past industrial emissions. Due to lead's immobility, it usually remains near the soil surface which increases the risk of an exposure. Children are more vulnerable to lead exposure due to mouthing behaviors, peaked interest in their surroundings, their developing nervous systems, and higher absorption from the gastrointestinal tract than in adults.