LEAD POLLUTION IN URBAN SOILS: A COMPARATIVE STUDY BETWEEN RESIDENTIAL AND RECREATIONAL SITES IN PHILADELPHIA, PA

In the United States, between the years of 1950 and 1995, large amounts of lead (Pb) were released into the atmosphere as fine particles from the use of leaded gasoline for cars and trucks, and the application of leaded paints. While the use of Pb additives in gasoline began to decline by the 1980’s, it wasn’t until 1995 that it was officially banned. Despite the fact that it has been 25 years since its ban, large amounts of Pb persists in the environment as dust, with dangerous concentrations in urban areas. Soils are the main source of urban Pb dust. Past studies have ranked the city of Philadelphia as having the eighth most contaminated urban soils in the United States. This study looks to test soils in areas from the inner and outer city, as well as from Philadelphia’s Fairmount Park (the largest city park in the country). The EPA limit of safe Pb concentrations in soil is 400ppm. This number was used to rate which soils on average contained Pb concentrations at or above this limit. Of the 31 samples collected so far, concentrations range from under 50ppm to well over ten times the EPA limit. It is well known that exposure to high levels of Pb in human populations, especially children, can lead to permanent damage to various parts of the body and has been linked to the formation of learning disabilities and sometimes brain damage. The most common route of exposure in young children is via hand to mouth, which is a concern in areas with high levels of dust and around homes with leaded paint. It is the hope of this study that the collected data will help the city of Philadelphia better understand the danger that Pb dust poses to public health, especially to those that live in condensed residential areas in the inner city and just out side of it. This study will help the city better understand what areas require more or less attention with remediation so as to begin the process of cleaning up.