Narrator: This is Science Today. A new technique that detects the chemical "fingerprints" of different sources of lead exposure may help researchers zero in on the causes of childhood lead poisoning, which is typically hard to do. Donald Smith, a professor of environmental toxicology at the University of California, Santa Cruz, tested the technique and says even though the United States has greatly reduced the major sources of lead, a large number of children still suffer from lead poisoning.
Smith: Because we've used lead for so long in a number of different industrial materials, including as an additive in gasoline. As a result of all those industrial activities and the use of lead as combustion in cars, there's enormous amounts of lead, essentially stockpiled in the dust and soil of urban areas.
Narrator: Another major source of lead exposure in children is lead-based paints in old, deteriorating housing.
Smith: The most prudent thing that parents can do to help reduce that potential exposure is just to be aware of how the children may be exposed and how they can, by keeping their environment clean - whether it be the household or the outside environment - how they can actually reduce the intake of lead to the child.
Narrator: For Science Today, I'm Larissa Branin.