Scorecard presents information about potential lead hazards in housing. Exposure to lead can cause serious health effects in young children and the fetus of a pregnant woman because lead disrupts normal neurological development. Harmful exposure to lead can cause learning difficulties, reduce intelligence and attention span, and permanently damage a child's brain and nervous system. For young children, lead exposure typcially occurs in and around the house as a result of deteriorated lead-based paint, lead-contaminated dust, and lead-contaminated soil. Young children -- especially toddlers -- are particularly at risk for exposure to small particles of lead because the normal behavior they use to explore their environments involves putting their hands and toys in their mouths.
The most recent national survey of children's blood lead levels, as well as numerous other studies, documents that older housing and lower income are associated with with elevated blood lead levels and lead hazards. Scorecard's two primary hazard indicators for identifying housing with a high risk of lead hazards are: housing built prior to 1950 and households with income below the poverty threshold. In addition, Scorecard looks to the number of children living in poverty in a certain area to identify possible areas with high risk of lead hazards. This indicator allows those studying the issue to focus on areas with young children who are at highest risk for lead poisoning.
DATA SOURCES AND LIMITS
The primary data source used to calculate lead risk factors is the 2000 Census. Other sources used to investigate lead hazards include the CDC reports, Surveillance for Elevated Blood Lead Levels Among Children -- United States, 1997-2001 and The Second National Report on Human Exposure to Environmental Chemicals.
Potential hot spots of lead hazards in housing are identified based on indicators, not lead monitoring data. Because local data on lead contamination are generally unavailable, Scorecard relies on housing and demographic indicators to identify areas with housing that has a high risk of lead hazards. Scientific studies have demonstrated that housing built prior to 1950 and households with income below the poverty threshold have an elevated risk of lead contamination.