Home About the Writer/editor Portfolio Science Writing Sample #1 Science Writing Sample #2 Newspaper Article #1 Newspaper Article #2 Editing Sample #1 Editing Sample #2 E-mail me

Writing This is a summary of a document that compiles information on the sources and hazards of lead in soil. It is one entry in an index of information on lead, written to help the reader determine whether the document it describes meets the reader's needs. NATIONAL LEAD INFORMATION CENTER A Summary of Studies Addressing the Source of Soil Lead June 1996 Background Lead, even at low dosages, may contribute to mental retardation and learning disabilities in exposed children. Because of their tendency to put things in their mouths and because their brains are still developing, young children are particularly at risk. This literature search assesses the sources and extent of lead contamination in soil, which may act as a vehicle through which children ingest lead. Objective This report reviews the scientific literature on the sources of elevated soil-lead concentrations. It identifies 36 such studies conducted after 1980, discusses the results of all these studies taken together (volume 1), and includes a summary of each study (volume 2). Conclusions The concentration and sources of soil lead in the United States have been assessed in many field studies, mostly in urban and smelter communities. The studies reviewed in this report were carried out in locations scattered throughout the United States. The studies investigate three sources of elevated lead in soil: lead-based paint on building walls; point sources such as smelters, battery dump sites, and mine tailings; and leaded-gasoline emissions from automobiles. Differentiating among these sources is difficult, and lead poisoning cannot usually be attributed to one of them exclusively. However, at the extremes the effects are clear: houses with highly contaminated soil were often found to be coated with lead-based paint, while soil lead concentrations near point sources and highways decreased rapidly with distance from the source. Many studies found high levels of lead in city centers. Several studies showed that children who played on lead-contaminated soil had high concentrations of lead in their blood; this effect was stronger in children who played on bare soil than in those who played on grass. Application Parents who live in houses painted outside with lead-based paint, in inner cities, near highways, or near industrial point sources such as smelters may be alerted to contamination in their children's play areas. In addition, this document may help state and local governments to pinpoint sources of contamination.